Title of Invention

OLIGOMERIC CHAIN EXTENDERS FOR PROCESSING, POST-PROCESSING AND RECYCLING OF CONDENSATION POLYMERS, SYNTHESIS, COMPOSITIONS AND APPLICATIONS

Abstract The invention provides chain extenders made from epoxy-functional (meth)acrylic monomers and styrenic and/or (meth)acrylic monomers. The invention further provides polymeric compositions made from the chain extenders and plastic articles made from the compositions. Finally, the invention provides methods of using the chain extenders to improve the properties of virgin, recycled, and reprocessed condensation polymers.
Full Text OLIGOMERIC CHAIN EXTENDERS FOR PROCESSING,
POST-PROCESSING AND RECYCLING OF CONDENSATION POLYMERS,
SYNTHESIS, COMPOSITIONS AND APPLICATIONS
FIELD OF THE INVENTION
The invention is directed to chain extenders made from epoxy-
functional monomers, polymeric compositions and articles made therefrom.
BACKGROUND OF THE INVENTION
Many condensation or step-growth polymers, including polyesters,
polyamides, polycarbonates, and polyurethanes are widely used to make plastic
products such as films, bottles, and other molded products. The mechanical and
physical properties of these polymers are highly dependent on their molecular
weights.
In a life cycle, these materials may experience a synthesis process,
followed by an extrusion step, and a final processing step which may be another
compounding/extrusion operation followed by profile or sheet forming,
thermoforming, blow molding, or fiber spinning, or they can be injection or otherwise
molded in the molten state. Typically, all of these steps occur under high temperature
conditions. In addition, in recent years, increased attention has been focused on
improved methods of reclaiming and recycling the plastics made from these polymers,
with an eye toward resource conservation and environmental protection. The
processing steps involved in recycling these polymers also involve high temperatures.
In each one of these high temperature steps, particularly during the
compounding/processing and reclaiming/recycling processes, some degree of polymer
molecular weight degradation occurs. This molecular weight degradation may occur

via high temperature hydrolysis, alcoholysis or other depolymerization mechanisms
well know for these polycondensates. It is known that molecular weight degradation
negatively affects the mechanical, thermal, and Theological properties of materials,
thus preventing them from being used in demanding applications or from being
recycled in large proportions for their original applications. Today, recycled or
reprocessed polycondensates with deteriorated molecular weights can only be used in
very low proportions in demanding applications or in larger proportions in less
demanding applications. For instance, due to molecular weight degradation, recycled
bottle grade polyethylene terephthalate (PET) is mostly employed exclusively in fiber
and other low end applications. Similarly, recycled polycarbonate from compact disk
(CD) scrap, mostly goes to low end applications. For these reasons, the current
recycling technologies are limited to a narrow range of applications.
Today, there exist a considerable number of processes in the art ,
employed to minimize loss in molecular weight and to maintain or even increase the
molecular weight of the polycondensates for processing or recycling. Most of these
routes employ as main processing equipment either an extruder, a solid state
polycondensation reactor, or both in sequence, or similar equipment designed for melt
or high viscosity material processing. As an instrumental part of any of these
processes, chemical reactants known in the art as "chain extenders" are employed.
Chain extenders are, for the most part, multi-functional molecules that are included as
additives in the reactor or extruder during any or all of the described processing steps
with the purpose of "re-coupling" polycondensate chains that have depolymerized to
some degree. Normally the chain extender has two or more chemical groups that are
reactive with the chemical groups formed during the molecular weight degradation
process. By reacting the chain extender molecule with two or more polycondensate
fragments it is possible to re-couple them (by bridging them), thus decreasing or even
reverting the molecular weight degradation process. In the art there are numerous
chain extender types and compositions, polycondensate formulations, and processing
conditions described to this end.
Di- or poly-functional epoxides, epoxy resins or other chemicals
having two or more epoxy radicals, are an example of chain extending modifiers that

have been used to increase the molecular weight of recycled polymers. These di- or
poly-functional epoxides are generally made using conventional methods by reacting
a epichlorohydrin with a molecule having two or more terminal active hydrogen
groups. Examples of such chain extenders include bis-phenol type epoxy compounds
prepared by the reaction of bisphenol A with epichlorohydrin, novolak type epoxy
compounds prepared by reacting novolak resins with epichlorohydrin, polyglycidyl
esters formed by reacting carboxylic acids with epichlorohydrin, and glycidyl ethers
prepared from aliphatic alcohols and epichlorohydrin. Additionally, various acrylic
copolymers have been used as polymer additives to improve the melt strength and
melt viscosity of polyesters and polycarbonates. These additives generally include
copolymers derived from various epoxy containing compounds and olefins, such as
ethylene. However, these chain extenders have met with limited success in solving
the problem of molecular weight degradation in reprocessed polymers. The ,
shortcomings of these copolymer chain extenders can be attributed, at least in part, to
the fact that they are produced by conventional polymerization techniques which
produce copolymers of very high molecular weight, which when coupled with a
polycondensate can dramatically increase the molecular weight leading to localized
gelation and other defects with physical characteristics which limit their capacity to
act as chain extenders.
Two main problems persist today in the art. First, in order to have
efficient chain extension at reasonable residence times (i.e., good productivity in a
given size equipment) either in the extrusion or solid state reactor systems, most of
the known chain extenders require the use of pre-dried polycondensate material,
operation at high vacuum, and varying amounts of catalyst and stabilizers, to be
employed during processing. Without these features the extent of molecular weight
increase is limited and the resulting product shows lower molecular weight and less
than desired properties.
Second, as the functionality of the chain extender increases, so does
the number of polycondensate chains that can be coupled onto each chain extender
molecule, and thus its effectiveness in re-building molecular weight. However, it is
easy to see that as the functionality of these chain extenders increase so does the

potential for onset of gelation. People skilled in the art are familiar with the strong
negative effects associated with extensive crosslinking on the degree of crystallinity
and thus on the mechanical properties of a semi-crystalline polycondensate, as well as
the negative implications of the presence of varying amounts of gel in any product.
As a result of these negative effects there is a limit for the maximum functionality that
can be employed with these chain extenders. Given, then, that the maximum
functionality is limited, effective chain extension currently requires relatively large
concentrations of lower functionality ( The relatively high costs associated with these two limitations of the
current art render the re-processing or recycling of these polycondensates
uneconomical.
Still other disadvantages are associated with the presently available
chain extenders. For example, phosphite-based chain extenders suffer from the
disadvantage of being highly volatile, high viscosity liquids which are cumbersome to
handle, susceptible to hydrolysis and suspected endocrine disrupters. Some ethylene
based epoxy-functional chain extenders have the disadvantage of having high
molecular weights compared to polycondensates, which alters the nature of resulting
chain extended polymer, minimizing motility, increasing the chance for gel formation,
and altering chemical resistance and clarity. Titanate- and zirconate-based chain
extenders have the disadvantages of high cost, induced color in the product, difficult
handling due to solvent dilutes, and viscosity reduction. Finally, isocyanate-based
chain extenders suffer from toxicity concerns, reactivity to moisture and general
handling problems.
Thus a need exists for chain extenders that may be used in any suitable
process while avoiding the processing limitations described above. Such chain
extenders would provide substantial economic advantage in processing, reprocessing
and recycling of polycondensates over existing chain extenders and the methods for
their use.

Summary of the Invention
The invention relates to novehaligomeric and low molecular weight polymeric chain extenders, to
methods for making the chain extenders, to methods for using the chain extenders to improve the
physical characteristics of polycondensates and blends of polycondensates and to products made
from the improved polycondensates and polycondensate blends. As used, herein, the terms
"polycondensates" and the term "condensation polymers" are used broadly and synonymously to
mean step-growth polymers. Thus, the for the purpose of this specification, the two terms may be
used interchangeably. The chain extenders of this invention are particularly well suited for use
with reprocessed or recycled plastics.
The chain extenders of this invention, which are made from epoxy-functional (meth)^ acrylic
monomers and non-functional (meth) acrylic and/or styrenic monomers, are characterized by
certain physical and chemical properties that make them particularly suited as chain extenders.
These properties can be tailored through the specific composition of the chain extenders and they
include molecular weight, epoxy equivalent weight (EEW), number average epoxy functionality
(Efn), and weight average epoxy functionality (Efw).
One aspect of the invention provides a chain-extended polymeric composition comprising a chain
t
extender comprising a polymerization product of at least one epoxy-functional (meth) acrylic
I monomer and at least one styrenic and/or (meth) acrylic monomer and at least one condensation
■ polymer; wherein the chain extender has an epoxy equivalent weight (EEW) of from 180 to 2800,
, a number-average epoxy functionality (Efn) value~6f"lesTThan IRTT^^weTght-average epoxy
functionality (Efw) value of up to 140, and a number-average molecular weight (Mn) value of less
i than 6000 and wherein at least a portion of the chain extender has reacted with at least a portion
! of the at least one condensation polymer to produce a chain-extended condensation polymer
j wherein the polymeric composition is substantially free of gel particles. ^-
Another aspect of the invention provides chain-extended polymeric compositions made from a
condensation polymer that has been chain extended with the chain extenders of the present
invention. The invention also provides plastic articles made from the chain-extended polymeric
compositions.


Yet another aspect of the invention provides a method for increasing the molecular
weight of a condensation polymer by reacting the condensation polymer with the chain
extenders of the present invention.
The chain extenders of the present invention provide several advantages over other
presently available chain extenders. For example, by combining low molecular weights
with low EEW values, the chain extenders are able to achieve a high degree of chain
binding without inducing gelation using only small quantities. In addition, the chain
extenders provide numerous processing advantages over other known chain extenders.
These advantages include, the minimization or even elimination of the need to pre-dry the
condensation polymer and the elimination of the need for a catalyst or high vacuum
processing conditions to achieve effective chain extension. In addition, because the chain
extenders of the invention are resistant to gelation, the chain extension may take place
over much shorter residence times and under higher processing conditions than other
chain extenders, making the processing more time and cost effective. Finally, unlike
many conventional chain extenders, the chain extenders provided herein do not require
solid state polymerization steps to increase the molecular weight of the polycondensates
to desired levels.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Fig. 1. Examples of torque vs. time traces for virgin PET and PET modified with chain
extender B at different loads and temperatures. Values of interest are maximum torque
following melting (Max. Torque, Inch Pounds - IP), time to maximum torque, and torque
at three (Torque - 1), five (Torque - 2), and seven minutes (Final Torque). Torque is
directly related to melt viscosity which in turn is directly related to molecular weight.
Fig. 2. Examples of torque vs. time traces for virgin PET and PET modified with chain
extender B and existing chain extenders (TGIG, triglycidyl isocyanurate and EPON®
1007, bisphenol A epoxy resin). Values of interest are maximum torque following
melting (Max. Torque, Inch Pounds - IP), time to maximum torque, and

torque at three (Torque - 1), five (Torque - 2), and seven minutes (Final Torque).
Torque is directly related to melt viscosity which in turn is directly related to
molecular weight.
DETAILED DESCRIPTION OF THE INVENTION
One aspect of this invention provides epoxy-functional oligomeric and
low molecular weight chain extenders for use with plastics, including reprocessed or
recycled plastics. The chain extenders are capable of reverting the post-processing
molecular weight decrease in different polycondensates from the minimum value
reached without chain extension, back to the initial molecular weight values or even
larger than the original molecular weight values, without the incidence of gel and
without adverse effects on mechanical, thermal, or Theological properties at a target
polycondensate molecular weight. This is accomplished through the proper design of
the chain extenders which make it possible to increase the molecular weight of
polycondensates such as polyesters, polyamides, polycarbonates and others, in a
controlled manner. In particular, this aspect of the invention provides chain extenders
made from the polymerization of at least one epoxy-functional (meth)acrylic
monomer and at least one non-functional styrenic and/or (meth)acrylic monomer.
The chain extenders are characterized by relatively low EEW values and relatively
low molecular weights.
The chain extenders of the present invention are epoxy-functional
styrene (meth)acrylic copolymers produced from monomers of at least one epoxy-
functional (meth)acrylic monomer and at least one non-functional styrenic and/or
(meth)acrylic monomer. As used herein, the term (meth)acrylic includes both acrylic
and methacrylic monomers. Examples of epoxy-functional (meth)acrylic monomers
for use in the present invention include both acrylates and methacrylates. Examples i
of these monomers include, but are not limited to, those containing 1,2-epoxy groups
such as glycidyl acrylate and glycidyl methacrylate. Other suitable epoxy-functional
monomers include allyl glycidyl ether, glycidyl ethacrylate, and glycidyl itoconate.

Suitable acrylate and methacrylate monomers for use in the chain
extenders include, but are not limited to, methyl acrylate, ethyl acrylate, n-propyl
acrylate, i-propyl acrylate, n-butyl acrylate, s-butyl acrylate, i-butyl acrylate, t-butyl
acrylate, n-amyl acrylate, i-amyl acrylate, isobornyl acrylate, n-hexyl acrylate, 2-
ethylbutyl acrylate, 2-ethylhexyl acrylate, n-octyl acrylate, n-decyl acrylate,
methylcyclohexyl acrylate, cyclopentyl acrylate, cyclohexyl acrylate, methyl
methacrylate, ethyl methacrylate, n-propyl methacrylate, n-butyl methacrylate, i-
propyl methacrylate, i-butyl methacrylate, n-amyl methacrylate, n-hexyl methacrylate,
i-amyl methacrylate, s-butyl-methacrylate, t-butyl methacrylate, 2-ethylbutyl
methacrylate, methylcyclohexyl methacrylate, cinnamyl methacrylate, crotyl
methacrylate, cyclohexyl methacrylate, cyclopentyl methacrylate, 2-ethoxyethyl
methacrylate, and isobornyl methacrylate. Non-functional acrylate and non-
functional methacrylate monomers include butyl acrylate, butyl methacrylate, methyl
methacrylate, iso-butyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate,
isobornyl acrylate and isobornyl methacrylate and combinations thereof are
particularly suitable. Styrenic monomers for use in the present invention include, but
are not limited to, styrene, alpha-methyl styrene, vinyl toluene, p-methyl styrene, t-
butyl styrene, o-chlorostyrene, vinyl pyridine, and mixtures of these species. In
certain embodiments the styrenic monomers for use in the present invention are
styrene and alpha-methyl styrene.
In one embodiment of the invention, the chain extenders contain about
50 % to about 80 % by weight, based on the total weight of the monomers, of at least
one epoxy-functional (meth)acrylic monomer and between about 20 % and about 50
% by weight of at least one styrenic monomer. In other embodiments, the chain
extenders contain between about 25 % and about 50 % by weight of at least one
epoxy-functional (meth)acrylic monomer, between about 15 % to about 30 % by
weight of at least one styrenic monomer, and between about 20 % and about §0 % by
weight of at least one non-functional acrylate and/or methacrylate monomer. In yet
another embodiment of the invention, the chain extenders contain about 50 % to about
80 % by weight, based on the total weight of the monomers, of at least one epoxy-
functional (meth)acrylic monomer and between about 15 % and about 45 % by weight

of at least one styrenic monomer and between about 0 % to about 5 % by weight of at
least one non-functional acrylate and/or methacrylate monomer. In still another
embodiment, the chain extenders contain between about 5 % and about 25 % by
weight of at least one epoxy-functional (meth)acrylic monomer, between about 50 %
to about 95 % by weight of at least one styrenic monomer, and between about 0 %
and about 25 % by weight of at least one non-functional acrylate and/or methacrylate
monomer.
The present invention is based, at least in part, on the inventors'
surprising discovery that styrene (meth)acrylic chain extenders having certain
physical properties produce superior results at lower loadings than conventional chain
extenders. Specifically, the inventors' have found that by combining low molecular
weights with low EEW values, the chain extenders are able to achieve a high degree
of chain binding without inducing gelation. This allows the present chain extenders to
be more effective at lower loadings than other chain extenders and produce chain
extended condensation polymers that are substantially free from gel particles. In
addition, these properties lead to a variety of processing advantages which will be
discussed in more detail below. As used herein, the phrase "substantially free from
gel particles" means the chain extension reaction takes place in such a manner that gel
particle formation is avoided to any extent.
Without wishing or intending to be bound to any particular theory of
the invention, the inventors believe the surprising advantages of the epoxy-functional
chain extenders of this invention result from favorable combinations of certain Efh,
PDI, and EEW values possessed by these oligomers and low molecular weight
polymers. These characteristics are believed to allow for the maximization of
polycondensate molecular weight increase at a given chain extender load, without the
incidence of gel and without adverse effects on the mechanical, thermal, or
rheological properties at a target polycondensate molecular weight. Specifically, the
present invention provides novel chain extenders having the following characteristics:
1) very high number average epoxy functionality(Efn): Efh values of up to about 30,
and, in some cases, even higher than 30, including Efh values ranging from 2 to 20,
and further including Efh values ranging from 3 to 10; 2) controlled PDI values

ranging from about 1.5 to about 5, including ranges from about 1.75 to about 4, and
further including ranges from about 2 to about 3.5; 3) low epoxy equivalent weight
(EEW): from about 2800 to about 180, including from about 1,400 to about 190, and
further including from about 700 to about 200; 4) very low molecular weights
(number average molecular weight (Mn) (Mw) chain extender into the polycondensate melt. The molecular weight ranges above
include various embodiments wherein Mn ranges from 1000 to about 5000, including
from 1500 to 4000, and further including from 2000 to 3000. The molecular weight
ranges above also include various embodiments wherein Mw ranges from 1500 to
about 18000, including from 3000 to 13000, and further including from 4000 to 8500.
In addition, the chain extenders possess a wide range of solubility parameters tailored
for high solubility in polycondensates. In various exemplary embodiments, the chain
extenders have an EEW of from about 180 to about 300, an Efh value from about 4 to
about 12 and a PDI of from about 1.5 to about 2.8. In other exemplary embodiments,
the chain extenders have an EEW of from about 300 to about 500, an Efh value of
from about 4 to about 12 and a PDI of from about 2.8 to about 3.2. In still other
exemplary embodiments, the chain extenders have an EEW of from about 500 to
about 700, an Efn value of from about 4 to about 12 and a PDI of from about 3.2 to
about 4.5.
The desired epoxy equivalent weight (EEW) is fixed by the desired
content of the epoxy-functional monomer employed {GMA or other). Additionally, at
a given EEW, the Efh per chain can be tailored from very low to very high (e.g. > 30)
by controlling the Mn of the oligomer. Moreover, for a given EEW the Efw can be
designed by altering the polydispersity index of the oligomer (PDI = Mw/Mn =
Efw/Efn) through changes in composition, processing conditions, and molecular
weight. Suitable values of Efw include values of up to about 140, or even higher than
140, including Efw values ranging from 3 to 65, and further including values ranging
from 6 to 45.
The chain extenders may by produced according to standard techniques well
known in the art. Such techniques include, but are not limited to, continuous bulk

polymerization processes, batch, and semi-batch polymerization processes.
Production techniques that are well suited for the chain extenders are described in
United States Patent Application No. 09/354,350 and United States Patent Application
No. 09/614,402, the entire disclosures of which are incorporated herein by reference.
1 Briefly, these processes involve continuously charging into a reactor at least one
epoxy-functional (meth)acrylic monomer, at least one styrenic and/or (meth)acrylic
monomer, and optionally one or more other monomers thaJ^e^qlj^m^rizable with
the epoxy-functional monomer, the styrenic monomer, and/or the (meth)acrylic
monomer. This process surprisingly produces oligomeric or low molecular weight
copolymer compositions having epoxy equivalent weights, number average epoxy
functionalities (Efh), weight average epoxy functionalities (Efw), and polydispersiry
indexes (PDI) (PDI=Efw -s- Efh) which dramatically increase the molecular weight of
reprocessed plastics without gelation when used in small quantities in the absence of
any pretreatment or additionaljca,taIysts.
The proportion of monomers charged into the reactor may be the same as
those proportions that go into the chain extenders discussed above. Thus, in some
embodiments, the reactor may be charged with about 50 % to about 80 %, by weight,
of at least one epoxy-functional (meth)acrylic monomer and with about 20 % to about
50 %, by weight, of at least one styrenic and/or (meth)acrylic monomer.
Alternatively, the reactor may be charged with from about 25 % to about 50 %, by
weight, of at least one epoxy-fimctional{meth)acrylic monomer and with about 50 %
to about 75 %, by weight, of at least one styrenic and/or (meth)acrylic monomer. In
other embodiments the reactor may be charged with from about 5 % to about 25 %, be
weight, of at least one epoxy-functional {meth)acrylic monomer and with about 75 %
to about 95 %, by weight, of at least one styrenic and/or (meth)acrylic monomer.
The reactor may also optionally be charged with at least one free radical
polymerization initiator and/or one or more solvents. Examples of suitable initiators
and solvents are provided in United States Patent Application No. 09/354,350.
Briefly, the initiators suitable for carrying out the process according to the present
invention are compounds which decompose thermally into radicals in a first order
reaction, although this is not a critical factor. Suitable initiators include those with

half-life periods in the radical decomposition process of about 1 hour at temperatures
greater or equal to 90°C and further include those with half-life periods in the radical
decomposition process of about 10 hours at temperatures greater or equal to 100°C.
Others with about 10 hour half-lives at temperatures significantly lower than 100°C
may also be used. Suitable initiators are, for example, aliphatic azo compounds such
as 1-t-amylazo-l-cyanocyclohexane, azo-bis-isobutyronitrile and 1-t-butylazo-
cyanocyclohexane, 2,2'-azo-bis-(2-methyl)butyronitrile and peroxides and
hydroperoxides, such as t-butylperoctoate, t-butyl perbenzoate, dicumyl peroxide, di-
t-butyl peroxide, t-butyl hydroperoxide, cumene hydroperoxide, di-t-amyl peroxide
and the like. Additionally, di-peroxide initiators may be used alone or in combination
with other initiators. Such di-peroxide initiators include, but are not limited to, 1,4-
bis-(t-butyl peroxycarbo)cyclohexane, 1,2-di(t-butyl peroxy)cyclohexane, and 2,5-
di(t-butyl peroxy)hexyne-3, and other similar initiators well known in the art. The »
initiators di-t-butyl peroxide and di-t-amyl peroxide are particularly suited for use in
the invention.
The initiator may be added with the monomers. The initiators may be added
in any appropriate amount, but preferably the total initiators are added in an amount
of about 0.0005 to about 0.06 moles initiator's) per mole of monomers in the feed.
For this purpose initiator is either admixed with the monomer feed or added to the
process as a separate feed.
The solvent may be fed into the reactor together with the monomers, or in a
separate feed. The solvent may be any solvent well known in the art, including those
that do not react with the epoxy functionality on the epoxy-functional (meth)acrylic
monomer(s) at the high temperatures of the continuous process described herein. The
proper selection of solvent may help decrease or eliminate the gel particle formation
during the continuous, high temperature reaction of the present invention. Such
solvents include, but are not limited to, xylene, toluene, ethyl-benzene, Aromatic-
100®, Aromatic 150®, Aromatic 200® (all Aromatics available from Exxon), acetone,
methylethyl ketone, methyl amyl ketone, methyl-isobutyl ketone, n-methyl
pyrrolidinone, and combinations thereof. When used, the solvents are present in any
amount desired, taking into account reactor conditions and monomer feed. In one

embodiment, one or more solvents are present in an amount of up to 40 % by weight,
up to 15 % by weight in a certain embodiment, based on the total weight of the
monomers.
The reactor is maintained at an effective temperature for an effective period of
time to cause polymerization of the monomers to produce a oligomeric or low
molecular weight chain extender from the monomers.
A continuous polymerization process allows for a short residence time within
the reactor. The residence time is generally less than one hour, and may be less than
15 minutes. In some embodiments, the residence time is generally less than 30
minutes, and may be less than 20 minutes.
The process for producing the chain extenders may be conducted using any
type of reactor well-known in the art, and may be set up in a continuous
configuration. Such reactors include, but are not limited to, continuous stirred tank »
reactors ("CSTRs"), tube reactors, loop reactors, extruder reactors, or any reactor
suitable for continuous operation.
A form of CSTR which has been found suitable for producing the chain
extenders is a tank reactor provided with cooling coils and/or cooling jackets
sufficient to remove any heat of polymerization not taken up by raising the
temperature of the continuously charged monomer composition so as to maintain a
preselected temperature for polymerization therein. Such a CSTR may be provided
with at least one, and usually more, agitators to provide a well-mixed reaction zone.
Such CSTR may be operated at varying filling levels from 20 to 100 % foil (liquid
full reactor LFR). In one embodiment the reactor is more than 50 % full but less than
100 % foil. In another embodiment the reactor is 100 % liquid full.
The continuous polymerization is carried out at high temperatures. In
one embodiment, the polymerization temperatures range from about 180°C to about
350°C, this includes embodiments where the temperatures range from about 190°C to
about 325°C, and more further includes embodiment where the temperatures range
from about 200°C to about 300°C. In another embodiment, the temperature may
range from about 200°C to about 275°C. Due to their high temperature synthesis the
chain extenders of this invention show high thermal stability when used later in chain

extending applications in condensation polymer compositions processed at similar
temperature ranges. In contrast other chain extenders presently available undergo
degradation and gas evolution under these conditions.
A second aspect of the invention provides chain extended polymeric
compositions made by reacting the chain extendersof the present invention with
condensation polymers to form a substantially gel free jshain extended condensation
polymer composition. Suitable condensation polymers include, but are not limited to,
polyesters (PEs), polyamides (PAs), polycarbonates (PCs), polyurethanes (PUs),
polyacetals, polysulfones, polyphenylene ethers (PPEs), polyether sulfones,
polyimides, polyether imides, polyether ketones, polyether-ether ketones,
polyarylether ketones, polyarylates, polyphenylene sulfides and polyalkyls. In one
embodiment of the invention the condensation polymer is a polyester selected from
the family of polyethylene terephthalates (PETs), polypropylene terephthalates ,
(PPTs), and polybutylene terephthalates (PBTs). In another embodiment the
condensation polymer is a reprocessed or recycled condensation polymer. As used
herein, the term reprocessed means a polymer reclaimed from a production facility
originally scrapped for not meeting quality control or specification targets. Amongst
these can be included products out of specification from compounding, extrusion, or
molding start-up and shut down production and/or products from general production
out of specification or otherwise not meeting product quality specifications. Also
included in the definition of reprocessed products are products processed to final use
form but not meeting product specifications, such as product out of caliber or
dimensions, color, shape, etc., or waste process material such as injection runners,
edges, trim and flashes, etc. As used herein the term recycled condensation polymer
means a condensation plastic reclaimed a posteriori from its final use from diverse
sources, this include but is not limited to scrap from soda bottles, detergent bottles,
plastic toys, engine components, assembled plastic components, films, fibers, CDs,
DVDs, and the like.
The polyesters may be homo- or copolyesters that are derived from
aliphatic, cycloaliphatic or aromatic dicarboxylic acids and diols or
hydroxycarboxylic acids. In addition, mixtures of these polyesters or of polyesters

with further plastics are also suitable, for example blends of PBT/PC,
PBT/acrylonitrile-butadiene-styrene (ABS), PET/PA, and the like. Their composition
will depend essentially on the desired properties for a specific end use. Such
polyesters are well known in the art. Particularly suitable polyesters are PET, PBT
and corresponding copolymers and blends, as exemplified by PBT/PC, PBT/ASA,
PBT/ABS, PET/ABS, PET/PC or also PBT/PET/PC, which predominantly contain the
indicated polyesters; PET and its copolymers as well as PBT blends being the
preferred choice in certain embodiments.
As used herein, the term polyamide includes various well known
polyamide resins. These include polyamides produced by polycondensing a
dicarboxylic acid with a diamine, polyamides produced by polymerizing a cyclic
lactam, and polyamides produced by co-polymerizing a cyclic lactam with a
dicarboxylic acid/diamine salt. The polyamides useful for this invention also include
polyamide elastomer resins. Polyamide resins that are particularly suitable for use in
the present invention include nylon 6, nylon 6-6, nylon 6-10, nylon 11, nylon 12, and
co-polymers and blends thereof.
As used herein, the term polycarbonate includes various well known
polycarbonate resins. These include aromatic polycarbonates produced by reactions
of bisphenols with carbonic acid derivatives such as those made from bis-phenol A
(2,2-bis(4-hydroxyphenyl)propane) and phosgene or diphenyl carbonate. Various
modified polycarbonates and copolycarbonates made from other types of bisphenols
such as those where phenolic radicals in the para position are bridged via C, O, S or
alkylene are also included. Polyester carbonates made from one or more aromatic
dicarboxylic acids or hydroxycarboxylic acids, bisphenols and carbonic acid
derivatives are also included. Polycarbonate resins made from bis-phenol A and
carbonic acid derivatives are particularly suitable for this invention.
The thermoplastic polyurethanes of the present invention may be made
by any conventional process, as known in the art. Typical polyurethanes are made
from a polyol intermediate and generally an equivalent amount of a polyisocyanate.
The polyol intermediate is generally a liquid polyether polyol or a polyester polyol or
combinations thereof.

Polyether polyols that are use to produce the polyurethanes are
generally made by reacting an alkylene oxide, such as propylene oxide, with a strong
base such as potassium hydroxide, optionally in the presence of water, glycols and the
like. Other polyethers which can be utilized include, but are not limited to, those
which are produced by polymerization of tetrahydrofuran or epoxides such as
epichlorohydrin, ethylene oxide, propylene oxide, butylene oxide, styrene oxide, for
example in the presence of Lewis catalysts such as boron trifluoride, or by the
addition of epoxides, optionally mixed or in succession, onto starter components with
reactive hydrogen atoms such as water, alcohols, ammonia, or amines.
The polyester polyols that may be used to form the thermoplastic
polyurethanes may be formed from the condensation of one or more polyhydric
alcohols with one or more polycarbpxylic acids. Examples of suitable polyhydric
alcohols include the following: ethylene glycol, propylene glycol such as 1,2- •
propylene glycol and 1,3-propylene glycol, glycerol; pentaerythritol;
trifnethylolpropane; 1,4,6-octanetriol; butanediol; pentanediol; hexanediol;
dodecanediol; octanediol; chloropentanediol, glycerol monallyl ether; glycerol
monoethyl ether, diethylene glycol; 2-ethylhexanediol-l,4; cyclohexanediol-1,4;
1,2,6-hexanetriol; 1,3,5-hexanetriol; l,3-bis-(2-hydroxyethoxy) propane, 1,4- and 2,3-
butylene glycol, neopentyl glycol, l,4-brs-(hydroxymethyl)cyclohexane, trimethy-
lolethane, together with di-, tri-, tetra-, and higher polyethylene glycols, di- and higher
polypropylene glycols, together with di- and higher polybutylene glycols, and the like.
Examples of polycarboxylic acids include the following: phthalic acid; isophthalic
acid; terephthalic acid; tetrachlorophthalic acid; maleic acid; dodecylmaleic acid;
octadecenylmaleic acid; fumaric acid; aconitic acid; trimellitic acid; tricarballylic
acid; 3,3'-thiodipropionic acid; succinic acid; adipic acid; malonic acid, glutaric acid,
pimelic acid, sebacic acid, cyclohexane-l,2-dicarboxyIic acid; 1,4-cyclohexadiene-
1,2-dicarboxylic acid; 3-methyl-3,5-cyclohexadiene-l,2-dicarboxylic acid and the
corresponding acid anhydrides such as tetrahydrophthalic anhydride,
hexahydrophthalic anhydride, tetrachlorophthalic anhydride,
endomethylenetetrahydrophthalic anhydride, acid chlorides and acid esters such as
phthalic anhydride, phthaloyl chloride and the dimethyl ester of phthalic acid,

dimerized and trimerized unsaturated fatty acids, optionally mixed with monomeric
unsaturated fatty acids, terephthalic acid monomethyl ester and terephthalic acid
monoglycol ester.
The polyacetals usable in the present thermoplastic resin compositions
are crystalline thermoplastic resins, sometimes called polyoxymethylene (POM).
Suitable polyacetals are, for example, the compounds obtainable from the reaction of
glycols, such as diethylene glycol, triethylene glycol, 4,4'-dioxethoxy diphenyl
dimethyl methane and hexane diol, with formaldehyde. Polyacetals suitable for use in
accordance with the present invention may also be obtained by the polymerization of
cyclic acetals. Other specific examples of polyacetals include formaldehyde
homopolymers and copolymers of trioxane (i.e., trimer of formaldehyde) and a small
amount of cyclic ethers such as ethylene oxide and 1,3-dioxane.
Chain extension of the polycondensates may be accomplished through
any conventional mean, many of which are known in the art. For example, chain
extension of the polycondensates may be accomplished through dry tumbling together
or cofeeding a chain extender with a desired polycondensate. The chain extender may
then be melt or solution blended with the polycondensate by methods well known in
the art, such as by reactive extrusion. In addition, other suitable formulation
ingredients such as pigments, fillers, reinforzants, or additives such as stabilizers,
antioxidants, lubricants, and/or any other additives known in the art needed for
specific applications may be added to the formula in typical amounts. Examples of
suitable reactors for reactive extrusion include single and twin screw extruders
systems, of different screw designs, configurations, L/D and compression ratios,
operating at suitable RPM's to provide the prescribed average residence times at
known feed rates. Other suitable reactors include Banbury mixers, Farrell continuous
mixers, Buss co-kneaders, and roll mills. These systems may operate at temperatures
above the Tg of the chain extender and above the Tg and/or Tm of the polycondensate
in what is known in the art as reactive extrusion. The average residence time in the
reactor may vary, but the chain extenders of the present invention need only short
residence times compared to other presently available chain extenders. Typically, the
residence times will range from about 0.5 to about 15 minutes. This includes

embodiments where the residence time is from about 1 minute to about 10 minutes
and further includes embodiments where the residence time is from about 2 minutes
to about 7 minutes.
The chain extending operations can be followed by plastic forming
operations such as extrusion, molding and fiber spinning. The reactive extrusion can
also take place within primary processing equipment without pre-compounding.
Alternatively, the compounding may be followed by a finishing step such as solid
state polymerization and may be processed in any reactor system and configuration
operating at temperatures above the Tg of the chain extender and between the Tg and
Tm of the polycondensate for an average residence time between 1 and 24 hours,
including from 2 to 18 hours, and further including 3 to 12 hours. Examples of
suitable reactors for solid state polymerization are well know in the art, and
operational modes of the same include batch, semi-batch and continuous solid state ,
polymerization. In one embodiment, the blend, co-feed, or separate-feed is processed
in a combination process comprising suitable arrays of reactive extrusion and solid
state polymerization processes known in the art, operating within the ranges given
above, and in which chain extender may be added to either or both stages.
Processing may be followed by a polymer recovery and a pelletization
stage to obtain pellets or granules of the chain extended polycondensates suitable for
further processing.
Because the chain extenders provide low EEWs they are effective
even in very small quantities. In some embodiments of the invention, the chain
extender is present in an amount of about 5 % (w/w) or less, about 3 % (w/w) or less,
about 2 % (w/w) or less, about 1 % (w/w) or less, and even about 0.5 % (w/w) or less,
based on the total weight of the mixture. This includes embodiments where the chain
extender is present in an amount of from about 0.01 to about 5 % (w/w), based on
total weight of the mixture, and further includes embodiments where the chain
extender is present in an amount of from about 0.03 to 4 %, or from about 0.05 to 2.5
% (w/w) based on the total weight of the mixture. It follows that the condensation
polymer may be present in an amount of up to 99.99 % (w/w), 99.95 % (w/w), 99.5 %

(w/w), 99 % (w/w), 98 % (w/w), 97 % (w/w), or 95 % (w/w) based on the total weight
of the mixture.
The chain extenders of the present invention provide a number of
processing advantages compared to other chain extenders. For example, pre-drying of
the polycondensate is not required prior to chain extension. This is of particular
commercial advantage as pre-drying adds cost and complexity to the process of
recycling by requiring another process step as well as more time. In addition, unlike
many of the chain extenders currently available, the chain extenders of the present
invention do not require the addition of a catalyst or high vacuum operation in order
to drive the reaction to the desired extent. This significantly reduces processing costs.
Thus, in various embodiments of the invention, the chain-extended condensation
polymers are substantially free of gel particles, are produced without pre-drying the
condensation polymer, and are produced by reacting the chain extenders and_the
condensation polymers in a single stage of conventional equipment in the absence of
additional catalyst and/or without vacuum operation. Furthermore, in some of these
embodiments, the chain extended polycondensates obtained have molecular weights
that are similar to or higher than those obtained through solid state polymerizaion, and
have properties that are similar or even better than those obtained through solid state
polymerization, thus allowing for the replacement of expensive and cumbersome solid
state polymerization processes by simpler reactive extrusion processes.
The chain extenders of the present invention have demonstrated
enhanced ability to restore or even improve the properties of reprocessed or recycled
condensation polymers or of lower grade virgin condensation polymers. The
improvements provided by the chain extenders can be seen directly in the physical
properties of the chain extended condensation polymers compared to the same
properties in the unmodified low grade virgin condensation polymers or reprocessed
or recycled condensation polymers. The efficacy of chain extension and molecular
weight increase can be assessed in a number of different ways. Some common
methods for the assessment of chain extension are change in melt viscosity, which
may be measured by capillary rheometry, melt flow index (MFI), cone-and-plate or
parallel plate rheometry. Other common methods are based on changes in solution

viscosity, which may be measured for example by Ostwall-Fenske or Ubbelohde
capillary viscometers as changes in relative, inherent, or intrinsic viscosity (I.V.).
The chain extenders of the present invention are very effective at
increasing the molecular weight of reprocessed or recycled condensation polymers.
This is evidenced by the increase in the intrinsic viscosity of the condensation
polymers following chain extension. For example, in some instances the chain
extenders may increase the intrinsic viscosity of the chain extended condensation
polymer back to within 15 % of the intrinsic viscosity of the condensation polymer
prior to recycling or reprocessing, where intrinsic viscosity is measured according to
ASTM D-2857. This includes embodiments where the intrinsic viscosity of the chain
extended condensation polymer may increase back to within 10 % of the intrinsic
viscosity of the condensation polymer prior to recycling or reprocessing, and further
»
includes embodiments where the intrinsic viscosity of the chain extended
condensation polymer may increase back to within 5 % of the intrinsic viscosity of the
condensation polymer prior to recycling or reprocessing.
In some cases, the intrinsic viscosity of the chain extended
condensation polymers is actually higher than the initial intrinsic viscosity of the
condensation polymers before they underwent recycling or reprocessing. This
includes embodiments where the intrinsic viscosity of the chain extended
condensation polymer is increased by at least 2 %, at least 5 %, at least 10 %, at least
20 %, at least 30 %, at least 40 %, and even at least 50 % with respect to the
condensation polymer from which the recycled or reprocessed condensation polymer
was produced. In some instances the chain extenders may increase the intrinsic
viscosity of the chain extended condensation polymers, as described above, without
any need from pre-drying the condensation polymer, catalyst, vacuum operation, or
solid state polymerization steps.
The increase in the viscosity of the condensation polymers following
chain extension may also be measured by melt viscosity as measured by capillary
rheometry. For example, in some instances the chain extenders may increase the melt
viscosity of the chain extended condensation polymer as measured by capillary
rheometry at 100 s"1, by up to 300 % relative to the initial post-processing melt

viscosity of the condensation polymer. This includes embodiments where this
increase in melt viscosity is realized without the need for any pre-drying of the
condensation polymer, catalyst, vacuum operation, or solid state polymerization steps.
The increase in the molecular weight of the condensation polymers
following chain extension is also demonstrated by the decrease in the melt flow index
(MFI) of the condensation polymer after chain extension has occurred. For example,
in some instances the melt flow index (MFI) of the chain extended condensation
polymer, as measured by ASTM-D-1238, may be only about 60 % or less of the MFI
of the reprocessed or recycled condensation polymer or of the initial MFI of a low
grade condensation polymer. This includes embodiments where this decrease in MFI
is realized in a melt blending process without the need for any pre-drying of the
condensation polymer, catalyst, vacuum operation, or solid state polymerization steps.
Due to their ability to provide recycled or processed materials with '
properties equivalent to those of the un-recycled or un-processed materials, the chain
extenders of the present invention have the advantage that more of the recycled or
reprocessed material can be incorporated into the final product. The chain extenders
have the further advantage that the mechanical, thermal and impact properties of
chain extended polycondensates are not negatively impacted and in many instances
are enhanced with respect to those of the un-recycled or un-processed
polycondensates.
The chain extenders may be used with lower grade virgin
polycondensates in order to make such polycondensates suitable for uses which they
otherwise would not be. For example, a chain extended lower grade condensation
polymer, such as a polyester, according to the invention, may have an intrinsic
viscosity that permits the polymer to be used in more demanding application. This
includes embodiments where the intrinsic viscosity of the chain extended lower grade
condensation polymer is increased by at least 2 %, at least 5 %, at least 10 %, at least
20 %, at least 30 %, at least 40 %, and even at least 50 % by reaction with a chain
extender. "Lower grade" polycondensate, as used herein, means a resin grade with
comparatively lower molecular weight with respect to other grades in the same
chemical family, exhibited as lower I.V., or lower melt viscosity at given conditions,

which also results in lower physical properties than the other grades in the same
family.
Applications of this invention include, but are not limited to, recycling
of scrap plastics, such as polyesters, polycarbonates, polyamides, and blends and
alloys of scrap plastics by either a reactive extrusion or a solid state polymerization
process of this invention, and post-processing of the recycled material through
extrusion/blow molding into various articles including, but not limited to, food or
non-food contact containers and transparent colored applications, films, coatings,
tapes, moldings, fibers, strapping and other consumer products.
In general the epoxy-functional oligomeric or polymeric chain
extenders of this invention show storage stability, safety of handling, no need for
catalysts for effective chain extension, resistance to hydrolysis, and low volatility.
The chain extenders may take the form of solids, or low viscosity liquids, or easy to
handle wax forms.
INDUSTRIAL APPLICABILITY
The chain extenders of this invention provide several benefits in a
variety of applications. These chain extenders when used by PET resin manufacturers
provide intrinsic viscosity enhancement in single reactive steps with no need for or
shorter solid state time, improvement in melt strength, improvement in compatibility
with other types of plastics, aid in processing due to reduced need for drying, and can
act as acetaldehyde scavengers. These chain extenders can be used in single reactive
extrusion equipment as substitutes for solid state polymerization in recycling of PET.
Compounders can benefit from the improved compatibility with other types of
plastics, such as other polyesters, polycarbonates, polyamides, etc. Converters can
benefit from improved extrusion blow molding and melt strength, injection blow-
molding, crystallinity and toughness in blow molding operations. In foamed sheets
benefits can be expected due to the countered effects of endothermic foaming agents.
In industrial fabrics the use of these chain extenders can improve coating adhesion,
tenacity and melt strength. Use of these chain extenders in tire cord can provide

improved coating adhesion, acid neutralization and metal complexation. In films,
these chain extenders can provide improved toughness, improved melt strength and
higher draw-down ratios. For fiber producers, the chain extenders of the disclosed
invention can provide improved tensile strength and improved dyeability when using
disperse, acid or basic dyes. In certain exemplary embodiments where the
condensation polymer is a polyester, the chain extender may contain about 50 % to
about 80 % by weight of at least one epoxy-functional (meth)acrylic monomer based
on the total weight of the monomers and between about 20 % and about 50 % by
weight of at least one styrenic and/or (meth)acrylic monomer.
These chain extenders also have several benefits when used with
polycarbonates. PC resin manufacturers can benefit from molecular weight
enhancement, branching agent-notch sensitivity and improved compatibility for alloys
with PET, PBT, polyamides, etc. The recyclers of PC can reclaim CD and digital '
video disks (DVD) for engineering applications and may also benefit due to the
stabilization of mixed source regrind due to the acid scavenging and metal chelating
properties of the chain extenders. Compounders of PC can benefit due to improved
compatibility with other types of plastics as well as due to an upgrade of high flow
resins. Plastic converters can benefit from aid in processing for long dwell time
moldings, reduced sensitivity to residual moisture, structural foamed parts with
endothermic foaming agents, improved melt strength for extrusions and reduced
sensitivity to metals (pigments, waxes). In certain embodiments where the
condensation polymer is a polycarbonate, the chain extender may contain about 45 %
to about 80 % by weight of at least one epoxy-functional (meth)acrylic monomer
based on the total weight of the monomers and between about 20 % and about 55 %
by weight of at least one styrenic and/or (meth)acrylic monomer.
In the area of polyamide resin manufacture the chain extenders of this
invention provide enhancement of inherent viscosity, improved compatibility for
alloys with PET, PC, PBT, POM, etc., and dimensional stability. For compounders of
polyamide resins, these chain extenders improve compatibility for alloys, upgrade
hydrolyzed material and aid in processing by reducing the need to pre-dry the
polymer. These chain extenders allow recycling of mixed carpet waste of PET and

PA. For converters of PA, these chain extenders improve fiber tenacity, improve
coating adhesion for tire cord, improve wear resistance and act as dye coupling
agents. In certain embodiments where the condensation polymer is a polyamide, the
chain extender may contain 25 % to about 55 % by weight of at least one epoxy-
functional (meth)acrylic monomer based on the total weight of the monomers and
between about 45 % and about 75 % by weight of at least one styrenic and/or
(meth)acrylic monomer.
In post-reaction finishing of POM resins, these chain extenders can act
as formaldehyde scavengers, acid scavenger-process aids, secondary scavenger and
branching agents to control crystallization, provide benefits in reduced warpage and
shrinkage and improve toughness and wear resistance. Compounders of POM resins
can benefit from these chain extenders due to their ability to acts as process aids (acid
scavengers), formaldehyde scavengers, fiberglass coupling agents, coupling agents for
impact modifiers and chelators for metals (pigments, waxes). The converters of POM
resins also benefit from the chain extenders of this invention due to their ability to act
as process aids and formaldehyde scavengers and their ability to improve wear
resistance, melt strength for extruded profiles, and paint and metallization adhesion.
For the manufacturers of PBT resins, the chain extenders of this
invention provide enhancement of inherent viscosity without solid state
polymerization and compatibilization for alloys. These chain extenders benefit the
compounders of PBT resins due to the use of lower cost impact modifiers and reduced
moisture sensitivity during processing. For converters of PBT resins, these chain
extenders act as process aids by improving melt viscosity. In some embodiments,
these resins may also chelate metals.
In the manufacture of TPU resins, the chain extenders of this invention
act as crosslinkers for magnetic tape coatings and as process aid to minimize moisture
damage. For the compounders of TPU resins, these chain extenders provide benefits
in ether-ester alloys, PVC, NBR, etc., and act as process stabilizers and as fiberglass
coupling agents. The converters of TPU resins can benefit from the upgrade of edge-
trim/regrind, improved melt strength of fibers and blown film, improved adhesion to

metals and fabrics, and foamed parts/sheet with endothermic chemical foaming
agents.
The invention is described in greater detail in the following, non-
limiting examples.
EXAMPLES
Preparation of Chain Extenders I:
Five different epoxy-functional chain extenders, labeled Chain
Extender A-E below, were designed and prepared in a 2 gal free radical continuous
polymerization reactor system according to the teachings of U.S. Patent Application
No. 09/354,350 and United States Patent Application No. 09/614,402. The specific
synthesis conditions and chain extender characterization parameters are given in
Table 1 below. The abbreviations used below are defined as follows, STY = styrene,
BMA = butyl methacrylate, MMA = methyl methacrylate, GMA = glycidyl
methacrylate. ,


Example 1.
Virgin PET of Intrinsic Viscosity (I. V.) = 0.75 dL/g (Eastapak 7352
from Eastman Chemicals) was processed through a single extrusion step with and
without the use of a chain extender. The extruder employed is a 30 mm, twin-screw,
with 5 temperature zones plus die, operating at Ti to Tn = 280°C, and 200 RPM. The
PET was used without pre-drying, no vacuum was employed during processing, and
no catalyst was employed.
Three chain extenders of this invention designed and prepared
according to the process described above were evaluated at different loads against a
large number of leading chain extenders known in the art. In each case the given
amount of chain extender was pre-mixed by dry blending to homogeneity with the
PET pellets before the mix was fed at constant rate into the extruder.
The I.V. results of the final compounds are given in Table 2 below.
The PET undergoes a marked molecular weight degradation during the prescribed

processing step starting from an I.V. of 0.750 dL/g before processing and decreasing
to 0.543 dL/g after extrusion.
In all cases the PET employed was Virgin Eastapak 7352 of I.V. = 0.75
dL/g from Eastman.

The abbreviations in Table 2 and other tables below are defined as
follows: EPON™ 100IF = Solid bis-phenol A glycidyl ether epoxy resin.
CYRACURE™ UVR6128 = a cycloaliphatic epoxy resin. STABAXOL™ KE7426 =

polymeric carbodiimide. STABAXOL™ P200 =a liquid carbodiimide. ERL-4221 =
a cycloaliphatic epoxy resin. IRGAFOS™ 168 = (2,4-di-tert-butyl phenyl) phosphite.
From these results it is absolutely clear that no noticeable chain
extension was achieved with any of the current art products tested under the
prescribed conditions. In contrast, all three tested chain extenders of this invention
caused a substantial increase in the final I.V. of the material, increasing it to values
from lower to higher than the value of the starting virgin material even at chain
extender loads'as low as 2 % w/w. In each case the product was substantially gel-
free.
Example 2.
Virgin PET of Intrinsic Viscosity (I.V.) = 0.75 dL/g (EASTAPAK™
7352 from Eastman Chemicals) was processed through a single extrusion step with
and without the use of chain extender. The different zone and die temperatures and
extruder RPM's were adjusted to maximize the I.V. of the product and are shown in
Table 3 below.
In this case the PET was pre-dried from an initial moisture value of
0.0947 % to a final value lower than the detection limit of the equipment. No vacuum
was employed during processing, and no catalyst was employed.
Three chain extenders of this invention were evaluated at 2 % w/w
against the current art chain extender showing best performance in example 1. In
each case the given amount of chain extender was pre-mixed by dry-blending to
homogeneity with the PET pellets before the mix was fed at constant rate into the
extruder.
The Intrinsic Viscosity (I.V.) results of the final compounds are given
in Table 3 below. Notice the marked molecular weight degradation in the pre-dried
PET control during the prescribed processing step, starting from an I.V. of 0.750 dL/g
before processing and decreasing to 0.592 dL/g after extrusion.


From these results it is clear that very limited chain extension was
achieved with the current art chain extender tested under the prescribed conditions. In
contrast, all three tested chain extenders of this invention caused a substantial increase
in the final I.V. of the material, increasing it to values from lower to similar to higher
than the value of the starting virgin material even at chain extender loads as low as 2
% w/w. No gel was observed in any of the products.
Example 3.
Virgin PET of Intrinsic Viscosity (I.V.) = 0.83 dL/g (MELINAR™
Laser C B95A, DuPont Chemical Company) was processed using a Brabender Plasti-
Corder. The PET was processed for 10 minutes at temperatures of 260°C and 280°C
and at a constant speed of 50 rpm. The PET was used without pre-drying, catalyst, or
vacuum during processing.
Three chain extenders of this invention (B, D, and E) designed and
prepared according to the process described above were evaluated at two temperatures
(260°C and 280°C) and two levels (0.5 and 2.0 % as w/w in mix). In each case the

given amount of chain extender was pre-mixed to homogeneity with the PET using a
Strand Mixer before the blend was fed into the mixing chamber. Examples of torque
vs. time traces are shown in Figure 1. Values of interest are maximum torque
following melting (Max. Torque, Inch Pounds - IP), time to maximum torque, and
torque at three (Torque - 1), five (Torque - 2), and seven minutes (Final Torque). In
this set of experiments torque is directly related to the melt viscosity, which is related
to its molecular weight. That is, greater torque is required to stir high molecular
weight PET materials.
The maximum torque following melting (Max. Torque, Inch Pounds -
IP), time to maximum torque, and torque at three (Torque - 1), five (Torque - 2), and
seven minutes (Final Torque) are recorded in Table 4 below for the modified and
unmodified PET samples at the temperatures and levels discussed above. From these
results it is clear that all three of the tested chain extenders of this invention caused
significant increases in the torque required to mix the PET samples reflecting an
increase in the polymer molecular weight. The maximum torque increased with the
level of modification and reaction temperature. The torque at three, five, and seven
minutes increased with the level of modification and decreased with temperature. No
gel was observed in any of the products.
In all cases the PET employed was Virgin MELINAR™ Laser C B95
2 of I.V. = 0.83 dL/g from DuPont.



Example 4.
Virgin PET of Intrinsic Viscosity (I.V.) = 0.83 dL/g (MELINAR™
Laser C B95A, DuPont Chemical Company) was processed using a Brabender Plasti-
Corder which consisted of a 100-mI mixing chamber. The PET was processed for 10
minutes at 280°C and at a constant speed of 50 rpm. The PET was used without pre-
drying, catalyst, or vacuum during processing.
One chain extender of this invention (B), designed and prepared
according to the process described above, that showed the best performance in
example 3 was evaluated against two current art chain extenders at 280°C and at 2%
w/w load. In each case the given amount of chain extender was pre-mixed to
homogeneity with the PET using a Strand Mixer before the blend was fed into the
mixing chamber. Examples of torque vs. time traces are shown in Figure 2. Values
of interest are maximum torque following melting (Max. Torque, Inch Pounds - IP),
time to maximum torque, and torque at three (Torque - 1), five (Torque - 2), and
seven minutes {Final Torque). In this set of experiments torque is directly related to
the blend viscosity, which is related to polymer molecular weight. That is, greater
torque is required to mix high molecular weight PET materials.
The maximum torque following melting (Max. Torque, Inch Pounds -
IP), time to maximum torque, and torque at three (Torque - 1), five (Torque - 2), and
seven minutes (Final Torque) are recorded in Table 5 below for the modified and
unmodified PET samples at the conditions described above. From these results it is
clear that no noticeable chain extension occurred with the current art chain extenders
during typical processing times of less than five minutes. On the other hand, chain
extender B of this invention caused a significant increase in the torque required to mix
the chain extended PET.


In all cases the PET employed was Virgin MELINAR™ Laser C B95
2 of I.V. = 0.83 dL/g supplied by DuPont.
Example 5.
The twin-screw extruder described in Examples 1 and 2 was used to
process polycarbonate (MAKROLON™ 2508 from Bayer) at 300°C, with and
without chain extender B of this invention. The polycarbonate and chain extender B
were dry blended to homogeneity and then fed to the extruder. Three different
concentrations of chain-extender were employed. No pre-drying, vacuum or catalyst
was employed in any example. The melt-flow index (MFI) of the processed
polycarbonate was measured in a plastiometer at 300°C per 1.2 Kg. Comparative
results are given in Table 6. The increase in MFI of the processed polycarbonate in
comparison with that of the un-processed control was caused by molecular weight
degradation. This MFI increase is overcome by use of 0.5 % w/w of chain extender
B. Higher levels of chain extender are more effective in increasing molecular weight
as judged from decrease in MFI.


Example 6.
The twin-screw extruder described in Examples 1 and 2 was used to
process four different grades of PET by dry-blending with chain extender B of this
invention at loadings of 1 and 2 % by weight. No pre-drying, vacuum or catalyst was
employed. The melt viscosity of resulting blends was compared with those of the
controls containing no chain extender with a capillary viscometer at 280°C and two
different shear rates. Results given in Table 7 show significant increase in melt
viscosity at both levels of chain extender of this invention. The melt viscosity values
at 1000 s"1 show an enhanced shear thinning for the chain extended materials of this
invention.

Preparation of Chain Extenders II:
Two different epoxy-functional chain extenders, labeled Chain
Extender F and G below, were designed and prepared in a 2 gal free radical
continuous polymerization reactor system operated in continuous recycle mode
according to the teachings of U.S. Patent Application No. 09/354,350. The specific
synthesis conditions and chain extender characterization parameters are given in
Table 8 below. The abbreviations used below are defined as follows: STY = styrene,

BMA = butyl methacrylate, MMA = methyl methacrylate, GMA = glycidyl
methacrylate.

Example 7. Controlled Chain Extension of Bottle Grade Processed PET
for Specific Enhanced Applications
Compositions comprising 98 to 99.7 parts of virgin PET of low Intrinsic Viscosity
(I.V.) = 0.8 dL/g (Eastapak 9921 W from Eastman Chemicals) was dry-blended and
then processed through a single extrusion step with 0.3 to 2.0 parts of chain extender
G of this invention. The extruder employed was a Maris-30, co-rotating 30 mm twin-
screw operating at T = 290°C and 200 RPM. No vacuum was employed during
processing, and no catalyst was employed.
Specific formulations were designed to enhance the I.V. of the final
product to the typical levels necessary for use in more demanding applications, thus

allowing this initially lower degraded I.V. feedstock to be used in such applications
otherwise not accessible due to their low properties.
The Intrinsic Viscosity (I.V.) results of the final compounds were
measured using a method adapted from ASTM D 4603-86, employing a Ubbelholde
viscometer series 1, and 60/40 Phenol/1,1,2,2 tetrachloroethane % (w/w) as solvent.
Results are given in Table 9 below. Large increases in I.V. are observed allowing the
application of the corresponding chain extended grades in applications previously
only reached with much higher initial I.V. PET resins.


From these results it can be seen that typical low I.V. grades of PET
normally used in less demanding fiber applications when formulated with about 0.3 %
of chain extender G can be used in sheet and tape, when formulated with about 0.5 %
of chain extender G can be used in non-food bottles, when formulated with about 1.0
% of chain extender G can be used in general purpose packaging strapping, and in
food grade bottles including CSD bottles, and when formulated with about 1.5 % of
chain extender G can be used in high-tensile strapping applications.
Preparation of Chain Extender Pre-Dilutions I:
To facilitate mixing of the chain extenders of this invention in
processing steps where traditionally insufficient mixing is achieved, such as injection
molding and some single screw extrusion operations, several pre-dilutions (PD) were
made by mixing 20 to 60 parts of chain extender G with 80 to 40 parts of different
suitable diluents. The description of these pre-dilutions is given below in Table 10.

Example 8. Applications in Injection-Molding
Compositions comprising 98 to 99.5 parts of high I.V. virgin PET (Eastapak EN-
001 I.V. = 0.75 from Eastman Chemicals) which were either pre-dried or undried
were mixed with 0.5 to 2 parts of several pre-dilutions containing varying amounts of
chain extender G of this invention, and then processed through a single injection
molding step. Injection molding was carried out in a Boy 50 injection molding
machine with a clamping force of 50 metric tons, fitted with a 28-mm injection screw
operating at T = 280°C. No vacuum was employed during processing, and no catalyst
was employed.

Comparative results of the mechanical properties of the moldings thus
obtained are given below in Table 11.

Compositions comprising 97 to 99 parts of low I.V. virgin PET (Eastapak EN-058
I.V. = 0.58 from Eastman Chemicals) which were either pre-dried, or partially pre-
dried were mixed with 1 to 3 parts of several pre-dilutions containing varying
amounts of chain extender G of this invention, and then processed through a single
injection molding step. Injection molding was carried out at same conditions as in
Example 8.
Comparative results of the mechanical properties of the moldings thus
obtained are given below in Table 12.


Example 10. Applications in Injection-Molding of PC
Compositions comprising 98.8 to 99.4 parts of virgin Polycarbonate
(Lexan 141 from GE Plastics) were pre-dried to less than 0.02 % moisture, then
mixed with 0.6 to 1.2 parts of Pre-dilutions R and S containing 50 % of chain
extender G of this invention, and then processed through a single injection molding
step. Injection molding was carried out in a Boy 50 injection molding machine with a
clamping force of 50 metric tons, fitted with a 28-mm injection screw operating at T =
300°C. No vacuum was employed during processing, and no catalyst was employed.
Comparative results of the mechanical properties of the moldings thus
obtained are given below in Table 13.


Example 11. Applications in Injection-Blow Molding of PET Bottles
from Low I.V. Feedstock
This example shows that with the aid of the chain extenders of this
invention, PET resins of I.V. lower than 0.75 can be successfully injection molded
into acceptable pre-forms and then blow molded into large bottles bearing similar
properties to those made from the higher I.V. resins (I.V. > 0.8) usually needed for
such applications. To show this application, injection-blow molding compositions
comprising 99.5 parts of virgin PET of I.V. = 0.73 (K3301 from Kosa) were pre-dried
to less man 0.02 % moisture, mixed with 0.5 parts of chain extender G of this
invention, and with 0.5 parts of Master Batch S (containing 50 % of chain extender
G), and then processed through a single injection molding step into standard 2 liter
bottle pre-forms (PRE-0246C). Formulations and injection molding conditions are
given below in Table 14. High I.V. = 0.84 PET resin (61802 from Wellman) was
used as a control for comparison.


The above performs were free-blown (FB) at 100°C and 60 psi of
pressure. The comparative results of the free-blown bottles thus obtained are shown
below in Table 15.


Example 12. Applications in Sheet Extrusion from Virgin, Recycled, or
Reprocessed Low I.V. Feedstock
In order to show the ability of the chain extenders of this invention to
enhance the performance of severely degraded polycondensate resins, virgin *
copolyester resin with I.V. = 0.8 (Eastar EN001 from Eastman Chemicals) was first
extruded without drying in a 27 mm co-rotating twin-screw extruder with L/D = 40
(Leistritz Micro 27). The resulting material (CoPE-lst Pass) with I.V. = 0.715 was
pelletized and used to make sheet compositions comprising 97 to 99.5 parts of CoPE-
1st Pass which was then pre-dried to less than 0.01 % moisture and then mixed with
0.5 to 3 parts of pre-dilutions X, Y and Z each containing 20 % of chain extender G of
this invention. Compositions were then processed in the same 27 mm extruder fitted
with a 7 inch flat sheet die operated with a temperature profile at the barrel zones
between 225°C at the feed and 300°C at the last zone, and 235°C at the die, under 25
mmHg vacuum. The 1st Pass CoPE resin was also processed into sheet under the
same conditions and used as a control. Intrinsic viscosity and mechanical properties
were measured as described above, melt viscosity was measured in a Rheometrics
Scientific SC-5000 operated in shear rate sweep mode widi 40 mm parallel plate
configuration at 0.5 mm gap.
The resulting sheet products show enhanced I.V. along with higher
rheological and mechanical properties. The sheet products also show enhanced
surface appearance, much less tendency to block and lower coefficients of friction

with itself. The latter is extremely important in sheet applications where sheets are
rolled or stacked and low blocking is needed.
Comparative results of the initial and final I.V. are given in Table 16.
Mechanical, rheological, and surface properties of the extruded sheets thus obtained
are given below in Table 17.



Example 13. Applications in Reclaiming Recycled, or Reprocessed Ultra
Low I.V. Feedstock
In order to show the ability of the chain extenders of this invention to
»
enhance performance of severely degraded reclaimed or reprocessed polycondensate
resins, 98 parts of lowest grade reclaimed PET (R-PET) resin with I.V. = 0.40 were
dried to less than 0.02 % moisture and then mixed with 2 parts of chain extender G of
this invention. This composition was then processed in a WP 30 mm co-rotating twin
screw extruder (L/D = 36) operating at 280°C and 150 RPM. No vacuum or catalyst
were used. The melt viscosity of the product at different shear rates was measured
against that of the unmodified control in a Kayeness Galaxy LCR6000 capillary
rheometer. Comparative results are given in Table 18. Virgin PET resin of I.V. =
0.73 (3302 from Kosa) from Example 2 has been added as a reference.


Example 14. Application in Thermoplastic Polyurethanes
In order to show the ability of the chain extenders of this invention to
enhance performance of different families of polycondensate resins, 98.5 to 99.5 parts
of Ether Based Thermoplastic Polyurethane (Elastolan 1185 from BASF) were dried
as per manufacturers recommendations and then mixed with 0.5 to 1.5 parts of chain
extender G of this invention. These compositions were then processed in the same
extruder of Example 13, operating at 200°C and 150 RPM. No vacuum or catalyst
were used. The melt viscosity of the products at different shear rates was measured
against that of the unmodified control as described in Example 13. Comparative
results are given in Table 19.

In order to show the ability of the chain extenders of this invention to
enhance performance of different families of polycondensate resins, 98.5 to 99.5 parts
of Polyether-Ester Elastomer (Hytrel 5556 from DuPont) were dried as per
manufacturers recommendations and then mixed with 0.5 to 1.5 parts of chain
extender G of this invention. These compositions were then processed in the same
extruder of Example 13, operating at 240°C and 150 RPM. No vacuum or catalyst
were used. The melt viscosity of the products at different shear rates was measured
against that of the unmodified control as described in Example 13. Comparative
results are given in Table 20.


Example 16. Application in PETG
In order to show the ability of the chain extenders of this invention
to enhance performance of different families of polycondensate resins, 98.5 to 99.5
parts of PETG (Eastar 6763 from Eastman Chemical) were dried as per manufacturers
recommendations and then mixed with 0.5 to 1.5 parts of chain extender G of this
invention. These compositions were then processed in the same extruder of Example
13, operating at 230°C and 150 RPM. No vacuum or catalyst were used. The melt
viscosity of the products at different shear rates was measured against that of the
unmodified control as described in Example 15. Comparative results are given in


Example 17. Application in PBT
In order to show the ability of the chain extenders of this invention
to enhance performance of different families of polycondensate resins, 98.5 to 99.5
parts of Polybutylene Terephthalate (PBT Ticona Celanex 2002) were dried as per
manufacturers recommendations and then mixed with 0.5 to 1.5 parts of chain
extender G of this invention. These compositions were then processed in the same
extruder of Example 13, operating at 260°C and 150 RPM. No vacuum or catalyst
were used. The melt viscosity of the products at different shear rates was measured
against that of the unmodified control as described in Example 13. Comparative
results are given in Table 22.
Table 21. Comparative Rheological Properties of Chain Extended PBT

Example 18. Application in Polycarbonate/Polyamide Blends
In order to show the ability of the chain extenders of this invention to
enhance performance of different blends of polycondensate resins, 98.5 to 99.5 parts
of a mix comprised of 80 % of polycarbonate (Makrolon 2608 from Bayer) and 20 %
of Polyamide 6 (Ultramid B3 from BASF) were dried separately as per manufacturers
recommendations, and then dry-blended with 0.5 to 1.5 parts of chain extender G of
this invention. These compositions were then processed in the same extruder of
Example 13, operating at 285°C and 150 RPM. No vacuum or catalyst were used.
The melt viscosity of the products at different shear rates was measured against that of

the unmodified control as described in Example 13. Comparative results are given in
Table 23.

Example 19. Application in Polycarbonate/Polyester Blends
In order to show the ability of the chain extenders of this invention to
enhance performance of different blends of polycondensate resins, 98.5 to 99.5 parts
of a mix comprised of 80 % of polycarbonate (Makrolon 2608 from Bayer) and 20 %
of polybutyleneterephthalate (1600A from Ticona Celanex) were dried separately as
per manufacturers recommendations, and then dry-blended with 0.5 to 1.5 parts of
chain extender G of this invention. These compositions were then processed in the
same extruder of Example 13, operating at 285°C and 150 RPM. No vacuum or
catalyst were used. The melt viscosity of the products at different shear rates was
measured against that of the unmodified control as described in Example 13.
Comparative results are given in Table 24.



Example 20. Application in Polyester/Polyamide Blends
In order to show the ability of the chain extenders of this invention to
enhance performance of different blends of polycondensate resins, 98.5 to 99 parts of
a mix comprised of 80 % polybutylenterephthalate (1600A from Ticona Celanex) and
20 % polyamide 6 (Ultramid B3 from BASF) were dried separately as per
manufacturers recommendations, and then dry-blended with 0.5 and 1.0 parts of chain
extender G of this invention. These compositions were then processed in the same *
extruder of Example 13, operating at 260°C and 150 RPM. No vacuum or catalyst
were used. The melt viscosity of the products at different shear rates was measured
against that of the unmodified control as described in Example 13. Comparative
results are given in Table 25.

Compositions comprising of 95 parts of polybutylenterephthalate
(Valox 325 from GE Plastics) were pre-dried to less than 0.05 % moisture, and then

parts of chain extender F of this invention, and compounded in a Leistritz 40-mm co-
rotating twin screw extruder operating at T = 250°C and 250 RPM. Injection molding
was carried out in a Boy 50 injection molding machine with a clamping force of 50
metric tons, fitted with a 28-mm injection screw operating at T = 275°C. No vacuum
was employed during processing, and no catalyst was employed.
Comparative results against the unmodified polyester of the
rheological, mechanical and thermal properties of the moldings thus obtained are
given below in Table 26.

Example 22. Applications in Injection-Molding of Polyamides
Compositions comprising 98.8 to 99.3 parts of pre-dried polyamide 6
were mixed with 0.5 and 1 parts of Pre-dilution S containing 50 % of chain extender
G of this invention, and with 0 to 0.2 parts of antioxidant (HD98 from Eastman
Chemical). These compositions were then compounded in a Brabender Plasticorder
operating at T = 230°C and 50 RPM for a residence time RT = 5 minutes.

Compounds thus obtained were granulated and then injection molded in a Daca
Microinjector operating at T = 230°C. No vacuum was employed during processing,
and no catalyst was employed.
Comparative results against the unmodified polyamide of the
Theological, and mechanical properties of the moldings thus obtained are given below
in Table 27, all methods employed have been described above.

Example 23. Applications in Fiber Enhancement
Compositions comprising 99.84 to 99.92 parts of pre-dried PET were
mixed with 0.08 to 0.16 parts of pre-dilution Q containing 60 % of chain extender G
of this invention. These compositions were then processed in a suitable reactor under
conditions of temperature and mixing as described above and spun into fibers of
different caliper through a die and spinneret. Fibers thus obtained were characterized
by Dynamic Mechanical Analyzer (Perkin Elmer Model 2980 DMA).

Comparative results against the unmodified polyester of the
dynamical-mechanical properties of the fibers thus obtained are given below in Table
28 all methods employed have been described above.

Example 24. Applications in Increasing Regrind or Recycle Content in
Formulations
Compositions comprising 0,10 or 50 parts of regrind of extruded PET
sheet were mixed with 100 to 50 parts virgin PET and various amounts of suitable
pre-dilution containing various amount of a chain extender of this invention. These
compositions were then processed into transparent sheet using the same equipment
and conditions as in Example 12.
Comparative results show that without the chain extender of this
invention the maximum regrind possible is about 10 % before loosing required
properties whereas the use of 2 % of the chain extender G allowed for 50 % regrind to
be processed into high quality sheet.
While certain embodiments have been illustrated and described, it
should be understood that changes and modifications can be made therein in
accordance with ordinary skill in the art without departing from the invention in its
broader aspects as defined in the following claims.

We claim:
1. A chain-extended polymeric composition comprising:
(a) a chain extender comprising a polymerization product of:
(i) at least one epoxy-functional (meth) acrylic monomer; and
(ii) at least one styrenic and/or (meth) acrylic monomer; and
(b) at least one condensation polymer;
wherein the chain extender has an epoxy equivalent weight (EEW) of from 180 to 2800, a
number-average epoxy functionality (Efn) value of less than 30, a weight-average epoxy
functionality (Efw) value of up to 140, and a number-average molecular weight (Mn)
value of less than 6000 and wherein the chain extender has reacted with at least one
condensation polymer in a single stage conventional equipment in the absence of
additional catalyst and/or without vacuum operation wherein the polymeric composition
is substantially free of gel particles.
2. The polymeric composition of claim 1, wherein the chain extender has a
polydispersity index of from 1.5 to 5.
3. The polymeric composition of claim 1, wherein the chain extender comprises 5 to
25 weight percent of the at least one epoxy-functional (meth)acrylic monomer
and 75 to 95 weight percent of the at least one styrenic and/or (meth)acrylic
monomer.
4. The polymeric composition of claim 1, wherein the chain extender comprises 25
to 50 weight percent of the at least one epoxy-functional (meth)acrylic monomer
and 50 to 75 weight percent of the at least one styrenic and/or (meth)acrylic
monomer.
5. The polymeric composition of claim 1, wherein the chain extender comprises 50
to 80 weight percent of the at least one epoxy-functional (meth)acrylic monomer
and 20 to 50 weight percent of the at least one styrenic and/or (meth)acrylic
monomer.

6. The polymeric composition of claim 1, wherein the chain extender has a weight
average molecular weight of less than 25,000.
7. The polymeric composition of claim 1, wherein the chain extender is made in a
reactor by a continuous polymerization process at a polymerization temperature of
from 180°C to 350°C with a residence time in the reactor of less than 60 minutes.
8. The polymeric composition of claim 1, wherein the chain extender is present in an
amount of less than-5 weight percent based on the total weight of the at least one
condensation polymer and the chain extender.
9. The polymeric composition of claim 1, wherein the at least one condensation
polymer is selected from the group consisting of polyesters, polyamides,
polycarbonates, polyurethanes, polyacetals, polysulfones, polyphenylene ethers,
polyether sulfones, polyimides, polyether imides, polyether ketones, polyether-
ether ketones, polyarylether ketones, polyarylates, polyphenylene sulfides and
polyalkyls.
10. The polymeric composition of claim 1, wherein the at least one condensation
polymer is a condensation polymer that has been recycled or reprocessed.
11. The polymeric composition of claim 10, wherein the chain-extended condensation
polymer has a molecular weight that is equal to or greater than the initial
molecular weight of the at least one condensation polymer prior to recycling or
reprocessing.
12. The polymeric composition of claim 10, wherein the chain-extended condensation
polymer has an intrinsic viscosity that is equal to or greater than the initial
intrinsic viscosity of the at least one condensation polymer prior to recycling or
reprocessing.

13. The polymeric composition of claim 1, wherein the at least one condensation
polymer is not pre-dried prior to the reaction of the chain extender with the at
least one condensation polymer.
14. The polymeric composition of claim 1, wherein the reaction of the chain
extender with the at least one condensation polymer is carried out in the absence
of a catalyst.
15. A plastic article made from the polymeric composition of
claim 1.
16. The plastic article of claim 15, wherein the plastic article is made using a process
selected from the group consisting of blow molding, injection molding, extrusion,
compression molding, rotational molding, calendaring, and fiber spinning.
17. The plastic article of claim 15, wherein the article is selected from the group
consisting of food containers, non-food containers, films, coatings, tapes,
moldings, fibers, extrusion profiles, and strapping.
18. A method for increasing the molecular weight of a condensation polymer
comprising reacting a chain extender comprising a polymerization product of:
(i) at least one epoxy-functional (meth)acrylic monomer; and
(ii) at least one styrenic and/or (meth)acrylic monomer;
with at least one condensation polymer wherein the chain extender has an epoxy
equivalent weight (EEW) of from 180 to 2800, a number-average epoxy
functionality (Efn) value of less than 30, a weight-average epoxy functionality
(Efw) value of up to 140, and a number-average molecular weight (Mn) of less
than 6000 and wherein the condensation polymer with increased molecular weight
is substantially free of gel particles.
19. The method of claim 18, wherein the chain extender has a polydispersity index of
from 1.5 to 5.

20. The method of claim 18, wherein the chain extender comprises 5 to 25 weight
percent of the at least one epoxy-functional (meth)acrylic monomer and 95 to 75
weight percent of the at least one styrenic and/or (meth)acrylic monomer.
21. The method of claim 18, wherein the chain extender comprises 25 to 50 weight
percent of the at least one epoxy-functional (meth)acrylic monomer and 75 to 50
weight percent of the at least one styrenic and/or (mefh)acrylic monomer.
22. The method of claim 18, wherein the chain extender comprises 50 to 80 weight
percent of the at least one epoxy-functional (meth)acrylic monomer and 50 to 20
weight percent of the at least one styrenic and/or (meth)acrylic monomer.
23. The method of claim 18, wherein the chain extender is made in a reactor by a
continuous polymerization process at a polymerization temperature of from
180°C to 350°C with a residence time in the reactor of less than 60 minutes.
24. The method of claim 18, wherein the chain extender has a weight average
molecular weight (Mw) of less than 25,000.
25. The method of claim 18, wherein the chain extender is present in an amount of
less than 5 weight percent based on the total weight of the at least one
condensation polymer and the chain extender.
26. The method of claim 18, wherein the at least one condensation polymer is
selected from the group consisting of polyesters, polyamides, polycarbonates,
polyurethanes, polyacetals, polysulfones, polyphenylene ethers, polyether
sulfones, polyimides, polyether imides, polyether ketones, polyether-ether
ketones, polyarylether ketones, polyarylates, polyphenylene sulfides and
polyalkyls.
27. The method of claim 18, wherein the at least one condensation polymer is a
condensation polymer that has been recycled or reprocessed.

28. The method of claim 27, wherein the chain-extended condensation polymer has a
molecular weight that is equal to or greater than the initial molecular weight of the
at least one condensation polymer prior to recycling or reprocessing.
29. The method of claim 27, wherein the chain-extended condensation polymer has
an intrinsic viscosity that is equal to or greater than the initial intrinsic viscosity
of the at least one condensation polymer prior to recycling or reprocessing.
30. The method of claim 18, wherein the at least one condensation polymer is not pre-
dried prior to reacting with the chain extender.
31. The method of claim 18, wherein reaction between the chain extender and the at
least one condensation polymer is carried out in the absence of a catalyst.
32. The method of claim 18, wherein reacting the chain extender with the at least one
condensation polymer is carried out, at least in part, by melt blending the chain
extender and the at least one condensation polymer at a temperature above the
glass transition temperature of the chain extender and above either the glass
transition temperature of the condensation polymer or above both the melting
temperature and the glass transition temperature of the condensation polymer.
33. The method of claim 32, wherein the melt blending takes place in a reactor
selected from the group consisting of a single screw extruder, a twin screw
extruder, a Banbury mixer, a Farrell continuous mixer, a Buss co-kneader, and a
roll mill.
34. The method of claim 32, wherein the melt blending takes place in a reactor and
the chain extender and the at least one condensation polymer have an average
residence time in the reactor of less than 15 minutes.
35. The method of claim 32, wherein the chain extender and the at least one
condensation polymer are pre-compounded prior to melt blending.

36. The method of claim 18, wherein reacting the chain extender with the at least one
condensation polymer is carried out, at least in part, through solid state
polymerization of the chain extender with the at least one condensation polymer
at a temperature above the glass transition temperature of the chain extender and
between the glass transition temperature and the melting temperature of the
condensation polymer.
37. The method of claim 36, wherein the solid state polymerization takes place in a
reactor and the chain extender and the at least one condensation polymer reactants
have an average residence time of less than 24 hours.


The invention provides chain extenders made from epoxy-functional (meth)acrylic monomers
and styrenic and/or (meth)acrylic monomers. The invention further provides polymeric
compositions made from the chain extenders and plastic articles made from the compositions.
Finally, the invention provides methods of using the chain extenders to improve the properties
of virgin, recycled, and reprocessed condensation polymers.

Documents:

1224-KOLNP-2004-(20-02-2012)-CORRESPONDENCE.pdf

1224-kolnp-2004-abstract.pdf

1224-kolnp-2004-assignment.pdf

1224-kolnp-2004-claims.pdf

1224-KOLNP-2004-CORRESPONDENCE 1.1.pdf

1224-KOLNP-2004-CORRESPONDENCE 1.2.pdf

1224-KOLNP-2004-CORRESPONDENCE 1.3.pdf

1224-KOLNP-2004-CORRESPONDENCE-1.5.pdf

1224-KOLNP-2004-CORRESPONDENCE.1.4.pdf

1224-kolnp-2004-correspondence.pdf

1224-kolnp-2004-description (complete).pdf

1224-kolnp-2004-drawings.pdf

1224-kolnp-2004-examination report.pdf

1224-KOLNP-2004-EXAMINATION REPORT1.5.pdf

1224-kolnp-2004-form 1.pdf

1224-kolnp-2004-form 18.pdf

1224-kolnp-2004-form 2.pdf

1224-kolnp-2004-form 3.pdf

1224-kolnp-2004-form 5.pdf

1224-kolnp-2004-form 6.pdf

1224-KOLNP-2004-GRANTED-ABSTRACT.pdf

1224-KOLNP-2004-GRANTED-CLAIMS.pdf

1224-KOLNP-2004-GRANTED-DESCRIPTION (COMPLETE).pdf

1224-KOLNP-2004-GRANTED-DRAWINGS.pdf

1224-KOLNP-2004-GRANTED-FORM 1.pdf

1224-KOLNP-2004-GRANTED-FORM 2.pdf

1224-KOLNP-2004-GRANTED-SPECIFICATION.pdf

1224-KOLNP-2004-OTHERS.pdf

1224-kolnp-2004-pa.pdf

1224-KOLNP-2004-PA_.pdf

1224-kolnp-2004-reply to examination report.pdf

1224-KOLNP-2004-REPLY TO EXAMINATION REPORT1.1.pdf

1224-kolnp-2004-specification.pdf


Patent Number 252333
Indian Patent Application Number 1224/KOLNP/2004
PG Journal Number 19/2012
Publication Date 11-May-2012
Grant Date 09-May-2012
Date of Filing 23-Aug-2004
Name of Patentee BASF CORPORATION
Applicant Address 1609 BIDDLE AVENUE, WYANDOTTE, MICHIGAN 48192, U.S.A.
Inventors:
# Inventor's Name Inventor's Address
1 BLASIUS, WILLIAM, GEORGE, JR. JOHNSON POLYMER, LLC, M/S 509, 8310 16TH STREET, STURTEVANT, WI 53177-0902
2 VILLALOBOS, MARCO JOHNSON POLYMER, LLC, M/S 509, 8310 16TH STREET, STURTEVANT, WI 53177-0902
3 DEETER, GARY JOHNSON POLYMER, LLC, M/S 509, 8310 16TH STREET, STURTEVANT, WI 53177-0902
PCT International Classification Number C08G 59/06
PCT International Application Number PCT/US2003/01230
PCT International Filing date 2003-01-15
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 60/353, 142 2002-02-01 U.S.A.