Title of Invention

SILANE-MODIFIED OXIDIC OR SILICEOUS FILLER

Abstract Silane-modified oxidic or siliceous filler with a bead fraction below 75 mm of less than 15 wt.% and a median particle size distribution between 150 and 500 mm, which is produced by the reaction of at least one microbeaded or microgranular, oxidic or siliceous filler in a compressed gas with at least one silane. The silane-modified oxidic or siliceous fillers are used in rubber compounds.
Full Text Silane-modified oxidic or siliceous filler, process for
its production and its use
The invention concerns a silane-modified oxidic or
siliceous filler, a process for its production and its
use.
The treatment of oxidic or siliceous compounds with
organosilicon compounds in order by this treatment to
strengthen the bond between the inorganic filler and the
organic polymer used in filler-reinforced elastomers and
thereby to improve the properties of the fillers in the
polymers is known.
It is known from DE 2141159, DE 2212239 and US 3,978,103
that sulfur-containing organosilicon compounds, such as
bis-(3-triethoxysilylpropyl) tetrasulfane or 3-
mercaptopropyl triethoxysilane, are used as the silane
coupling agent or reinforcing filler in oxidic-filled
rubber compounds, inter alia for tyre treads and other
parts of car tyres.
In order to circumvent the considerable problems that
arise during the processing of mercaptosilanes, such as
pre-scorch, scorch and plasticity properties for example,
it is known that mostly polysulfidic organosilanes, such
as for example bis-(3-triethoxysilylpropyl) tetrasulfane
or bis-(3-triethoxysilylpropyl) disulfane (DE 2542534,
DE2405758, DE19541404, DE19734295), which for silica-
filled vulcanisates represent a compromise in terms of
vulcanising safety, simple production and reinforcing
performance, can be used as a coupling agent for tyre
components.
The known incorporation of the corresponding additives,
especially organosilanes and the unmodified fillers, into
the unvulcanised polymer blends can be performed in
various ways.
The in-situ method involves a joint process for mixing
fillers, such as carbon black and silica, with
organosilanes and the polymers used.
The ex-situ method involves modifying the filler with the
corresponding organosilane or a mixture of various
organosilanes, before the filler is processed with the
polymer to form the unvulcanised rubber mix.
Also known is the addition of organosilanes in liquid form
(US 3,997,356) during production of the unvulcanised mix
for rubber compounds or the addition of the active filler
via a physical mixture of organosilane and filler prepared
in advance (DE 3314742, US 4,076,550). The disadvantage of
these mixtures, which have undergone no thermal
pretreatment, is the poor storage stability and hence the
often inadequate property stability of the products.
US-PS 4,151,154 describes oxidic siliceous fillers whose
surface is treated with two different types of
organosilicon compounds. The oxidic particles are treated
in such a way that they display a greater affinity to
water and can also be dispersed more easily in aqueous
systems.
The modification of kaolin suspended in water with various
organosilanes is known from US 3,567,680. However, the
organosilicon compounds that are described are water-
soluble in the quantities required for modification, such
that in this case the filler can be treated from an
aqueous solution.
US 4,044,037 describes aryl polysulfides and mineral
fillers treated with these compounds, which are used in
rubber compounds. They are produced in an aqueous/alcohol
formulation containing 80 to 99.9 wt.% alcohol.
A process is also known from EP-PS 01 26 871 wherein the
surface of siliceous fillers is modified with the aid of
an aqueous emulsion of water-insoluble organosilicon
compounds.
It is known that the surface of fillers can be modified by-
dissolving the organosilicon compound in an organic
solvent with subsequent treatment of the fillers, e.g.
clays (US 3,227,675).
The known processes for modifying fillers for rubber and
plastic applications with surface-active organosilanes or
mixtures thereof have the disadvantage of being based on
the use of water, organic solvents or direct spraying of
the organosilicon compound onto the surface of the filler
with a subsequent heat treatment, the conditioning
reaction. The known water-insoluble rubber-typical
organosilanes can often be effectively chemically bonded
with fillers only in hydrocarbon-based solvents, most of
which are toxic and readily flammable.
The known fillers modified ex situ with organosilanes have
the disadvantage that until now the rubber properties have
tended to be not better but in fact poorer than is the
case with fillers and silanes mixed together in situ.
In addition, in the case of fillers having a large
specific surface area or a pronounced surface texture,
silanisation is often not homogeneous. Diffusion of the
silane molecules into underlying layers of highly porous
fillers, such as precipitated silicas for example, can be
achieved only incompletely if at all with the modification
methods known until now. Macroscopically preformed fillers
are therefore modified only inadequately and incompletely
by the known silanisation processes.
In addition, preformed fillers cannot be silanised
successfully and non-destructively or with low abrasion by
means of the known silanisation processes and the
subsequent drying process that is often necessary. The
structure of preformed fillers is or would be destroyed or
damaged with the known processes (US 4,151,154; DE 3314742
C2; US 3,567,680). Thus for example silica granules formed
on rolls (DE 3014007) are very rapidly broken down into a
poorer quality silica powder (higher dust and fines
content) by being introduced into a mixer or similar
equipment and kept in motion for an extended period of
time.
A process for reacting at least one biopolymeric,
biooligomeric, oxidic or siliceous filler in a compressed
gas with at least one silane is known from DE 10122269.6.
The use of powdered and granular fillers therein described
is disadvantageous. Powdered silicas are disadvantageous
in industrial conditions, for example because of their
high dust content, low bulk density, poor flow properties
and hence commonly poor meterability. Granules can
subsequently be obtained from powdered silicas by
mechanical compaction. Since this means an additional
processing step, manufacturers try to avoid such processes
due to economic considerations. These granules easily
break down again into the powdered starting material under
mechanical loading and in addition the applicational
properties of the silicas frequently deteriorate due to
the subsequent granulation and associated mechanical
loading of the particles.
The object of the present invention is to produce a low-
dust silane-modified oxidic or siliceous filler directly
from a low-dust microbeaded or microgranular, oxidic or
siliceous filler. The silane-modified oxidic or siliceous
filler should display a satisfactory, quantitatively
easily variable coverage with the corresponding rubber-
reactive silanes and moreover comparable or better
properties than known silane-filler mixtures produced in
situ and moreover better rubber properties in the rubber
than known silane-filler mixtures produced ex situ.
A further object of the invention is to be able to work or
process the microbeaded or microgranular, oxidic or
siliceous filler to be modified in a low-dust supply form.
The external, macroscopic shape of these preformed
microbeaded or microgranular, oxidic or siliceous fillers
should be largely maintained during the modification
process. A largely dust-free or low-dust silane-modified
oxidic or siliceous filler should be obtained.
A further object of the present invention is to provide a
process for modifying microbeaded or microgranular, oxidic
or siliceous fillers with silanes, wherein the
modification reaction is not performed in water or organic
solvents.
The invention provides a silane-modified oxidic or
siliceous filler, which is characterised in that the bead
fraction below 75 mm (fines or dust content) is less than
15 wt.%, preferably less than 10 wt.%, particularly
preferably less than 7 wt.%, especially preferably less
than 5 wt.%, determined by screen analysis, and that the
median particle size is between 130 mm and 500 mm,
preferably between 130 mm and 450 mm, particularly
preferably between 150 mm and 400 mm, especially
preferably between 175 mm and 350 mm, determined by laser
diffraction without ultrasonic treatment.
The filler according to the invention can display a
statistically determined mean shape factor greater than
0.805, preferably greater than 0.82, particularly
preferably greater than 0.84, especially preferably
greater than 0.86.
The filler according to the invention can display a
statistically determined mean circle factor greater than
0.55, preferably greater than 0.57, particularly
preferably greater than 0.60, and especially preferably
greater than 0.62.
The filler according to the invention can display
micropores in the preferably between 0 and 0.3 ml/g, particularly preferably
between 0 and 0.1 ml/g.
The filler according to the invention can display
mesopores in the range between 2 and 30 run of between 0
and 1 ml/g, preferably between 0 and 0.75 ml/g,
particularly preferably between 0 and 0.5 ml/g.
The filler according to the invention can display
mesopores in the range between 2 and 50 nm of between 0
and 5 ml/g, preferably between 0 and 2.5 ml/g,
particularly preferably between 0 and 1.5 ml/g.
The filler according to the invention can display
macropores in the range above 30 nm of between 0 and
10 ml/g, preferably between 0 and 7.5 ml/g, particularly
preferably between 0 and 5 ml/g.
The filler according to the invention can display
macropores in the range above 50 nm of between 0 and
10 ml/g, preferably between 0 and 7.5 ml/g, particularly
preferably between 0 and 5 ml/g.
The filler according to the invention can display a BET
surface area of between 0.5 m2/g and 500 m2/g, preferably
between 0.5 and 300 m2/g, particularly preferably between
0.5 and 250 m2/g.
The filler according to the invention can display Sears
numbers (consumption of 0.1 KOH) of between 1 and 50 ml
per 5 g sample.
The filler according to the invention can display a sulfur
content in pure or chemically bonded form of between 0.05
and 25 wt.%, preferably between 0.05 and 10 wt.%,
particularly preferably between 0.05 and 4 wt.%.
The filler according to the invention can display a carbon
content in pure or chemically bonded form of between 0.1
and 25 wt.%, preferably between 0.1 and 10 wt.%,
particularly preferably between 0.1 and 5 wt.%.
The filler according to the invention can display a
content of physically and chemically bonded alcohol of
between 0 and 25 wt.%, preferably between 0 and 15 wt.%,
particularly preferably between 0 and 10 wt.%.
The filler according to the invention can display a
chemically or physically bonded residual content of the
alcohol deriving from the silane of less than 75 mol%,
preferably less than 50 mol%, particularly preferably less
than 30 mol%, especially preferably less than 20 mol%, of
the initial amount of alcohol in the silane used.
The silane-modified oxidic or siliceous filler according
to the invention can be predominantly bead-shaped,
spherical, round and/or homogeneously shaped.
The silane-modified oxidic or siliceous filler according
to the invention can be obtainable by reacting at least
one microbeaded or microgranular, oxidic or siliceous
filler in a compressed gas with at least one silane.
The silane-modified oxidic or siliceous filler according
to the invention can contain 0.1 to 50 wt.%, preferably
0.1 to 25.0 wt.%, particularly preferably 0.1 to 10 wt.%
silane.
The silane-modified oxidic or siliceous filler according
to the invention can contain 50 to 99.9 wt.% microbeaded
or microgranular, oxidic or siliceous filler.
The bead distribution in the silane-modified oxidic or
siliceous filler according to the invention, which can be
determined by screening, can be the same as or similar to
the bead distribution in the untreated microbeaded or
microgranular, oxidic or siliceous filler determined by-
screening.
The percentage difference in the bead fractions,
determined by screen analysis, between the starting
material, a microbeaded or microgranular, oxidic or
siliceous filler, and the end product, a silane-modified
oxidic or siliceous filler, for the bead fraction below
75 mm and the bead fraction between 75 and 150 mm, can be
not more than 100 wt.%, preferably not more than 75 wt.%,
particularly preferably not more than 50 wt.%, especially
preferably not more than 20 wt.%.
The ratio of the two screen fractions >3 00 mm and 150 mm -
300 mm can be less than 10:1, preferably less than 7:1,
particularly preferably less than 4:1.
The silane-modified oxidic or siliceous filler according
to the invention can display a bead fraction above 1000 mm
of less than 30 wt.%, preferably less than 20 wt.%,
particularly preferably less than 10 wt.%.
The silane-modified oxidic or siliceous filler according
to the invention can display a bead fraction above 500 mm
of less than 30 wt.%, preferably less than 20 wt.%,
particularly preferably less than 10 wt.%.
The silane can be chemically and/or physically bonded to
the surface of the fillers.
The invention also provides a process for the production
of a silane-modified oxidic or siliceous filler, which is
characterised in that at least one microbeaded or
microgranular, oxidic or siliceous filler is reacted with
at least one silane in a gas compressed by means of
pressure and/or temperature.
An organosilicon compound or mixtures of organosilicon
compounds having the general formula (I)
Z-A-Sx-A-Z (I)
can be used as the silane, in which formula
x is a number from 1 to 14, preferably 1 to 8,
particularly preferably 2 to 6,
Z equals SiX1X2X3 and
X1, X2, X3 can each mutually independently denote hydrogen
(-H),
halogen (-C1, -Br, -I) or hydroxy (-0H),
an alkyl substituent, preferably methyl, ethyl, propyl or
butyl,
an alkyl acid substituent (CxH2x+1) -C(=0)0-, alkenyl acid
substituent, for example acetoxy CH3-(C=O)O-,
a substituted alkyl or alkenyl acid substituent, for
example oximato- R12C=NO-,
a linear or branched, cyclic hydrocarbon chain with 1-8
carbon atoms,
a cycloalkane radical with 5-12 carbon atoms,
a benzyl radical or a halogen- or alkyl-substituted phenyl
radical,
alkoxy groups, preferably (C1-C24) alkoxy, particularly
preferably methoxy (CH3O-) or ethoxy (C2H5O-), and
dodecyloxy (C12H25O-) , tetradecyloxy (C14H29O-) , hexadecyloxy
C16H33O-) and octadecyloxy- (C18H37O-), with linear or
branched hydrocarbon chains having (C1-24) atoms,
alkoxy groups with linear or branched polyether chains
having C1-C24 atoms,
a cycloalkoxy group having (C5-12) atoms,
a halogen- or alkyl-substituted phenoxy group or
a benzyloxy group,
A is a linear or branched, saturated or unsaturated
aliphatic, aromatic or mixed aliphatic/aromatic divalent
hydrocarbon chain comprising C1-C30, preferably C1-C3,
particularly preferably (-CH2-), (-CH2-)2, (-CH2-)3,
(-CH(CH3)-CH2-) or (-CH2-CH(CH3)-) .
A can be linear or branched and can contain saturated as
well as unsaturated bonds. Rather than hydrogen
substituents, A can be provided with a wide range of
substituents, such as e.g. -CN, halogens, for example -Cl,
-Br or -F, alcohol functionalities -OH, alkoxides -OR1 or
-O-(C=O)-R1 (R1 = alkyl, aryl). CH2, CH2CH2, CH2CH2CH2,
CH2CH (CH3) , CH2CH2CH2CH2 , CH2CH2CH (CH3) , CH2CH (CH3) CH2,
CH2CH2CH2CH2CH2, CH2CH (CH3) CH2CH2, CH2CH2CH (CH3) CH2,
CH(CH3)CH2CH(CH3) or CH2CH (CH3) CH (CH3) can preferably be
used as A.
The following compounds can be used for example as the
silane having the general formula (I):
[(MeO)3Si(CH2)3]2S, [(MeO)3Si(CH2)3]2S2/ [ (MeO) 3Si (CH2) 3]2S3,
[(MeO)3Si(CH2)3]2S4, [ (MeO)3Si(CH2)3]2S5, [ (MeO) 3Si (CH2) 3] 2S6,
[ (MeO)3Si(CH2)3]2S7, [ (MeO)3Si(CH2)3]2S8, t (MeO) 3Si (CH2) 3] 2S9,
[(MeO)3Si(CH2)3]2Sio, [ (MeO)3Si(CH2)3]2Su,
t(MeO)3Si(CH2)3]2Si2, [(EtO)3Si(CH2)3]2S, [ (EtO) 3Si (CH2) 3] 2S2,
[(EtO)3Si(CH2)3]2S3, [(EtO)3Si(CH2)3]2S4, [ (EtO) 3Si (CH2) 3] 2S5,
[(EtO)3Si(CH2)3]2S6, [(EtO)3Si(CH2)3]2S7, [ (EtO) 3Si (CH2) 3] 2S8,
t (EtO)3Si(CH2)3]2S9, [ (EtO)3Si(CH2)3]2S10, [ (EtO) 3Si (CH2) 3] 2Su,
[ (EtO) 3Si (CH2) 3] 2Si2, [ (EtO) 3Si (CH2) 3] 2Si3,
[(EtO)3Si(CH2)3]2Si4, [(C3H7O)3Si(CH2)3]2S,
[ (C3H7O) 3Si (CH2) 3] 2S2, [ (C3H7O) 3Si (CH2) 3] 2S3,
[ (C3H7O) 3Si (CH2) 3] 2S4, [ (C3H7O) 3Si (CH2) 3] 2S5,
t (C3H7O) 3Si (CH2) 3] 2S6, t (C3H7O) 3Si (CH2) 3] 2S7,
[ (C3H7O) 3Si (CH2) 3] 2S8, t (C3H7O) 3Si (CH2) 3] 2S9,
[ (C3H7O) 3Si (CH2) 3] 2S10, [ (C3H7O) 3Si (CH2) 3] 2Su,
[(C3H7O)3Si(CH2)3]2Si2/ [(C3H7O)3Si(CH2)3]2Si3 or
[(C3H7O)3Si(CH2)3]2Si4
or (Ci2H25O) (EtO)2Si(CH2)3]Sx[(CHi)3Si(OEt)3] ,
t(Ci2H25O)2(EtO)Si(CH2)3]Sx[(CH2)3Si(OEt)3],
[(Ci2H25O)3Si(CH2)3]Sx[(CH2)3Si(OEt)3],
[ (Ci2H25O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (Ci2H25O) (OEt) 2] ,
[(Ci2H25O)2(EtO)Si(CH2)3]Sx[(CH2)3Si(C12H25O) (OEt)2],
[(Ci2H25O)3Si(CH2)3]Sx[(CH2)3Si(Ci2H25O) (OEt)2] ,
[ (Ci2H25O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C12H25O) 2 (OEt) ] ,
[ (Ci2H25O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (Ci2H25O) 2 (OEt) ] ,
[ (Ci2H25O) 3Si (CH2) 3] Sx[ (CH2) 3Si (Ci2H25O) 2 (OEt) ] ,
[ (C12H25O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C12H25O) 3] ,
[ (C12H25O)2(EtO)Si(CH2)3]Sx[ (CH2)3Si(C12H25O)3] ,
[ (C12H25O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C12H25O) 3] ,
(C14H29O) (EtO)2Si(CH2)3]Sx[ (CH2) 3Si (OEt) 3] ,
[ (C14H29O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (OEt) 3] ,
[ (C14H29O) 3Si (CH2) 3] Sx[ (CH2) 3Si (OEt) 3] ,
[(C14H29O) (EtO)2Si(CH2)3]Sx[(CH2)3Si(C14H29O) (OEt) 2],
[ (C14H29O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C14H29O) (OEt) 2] ,
[(C14H29O)3Si(CH2)3]Sx[(CH2)3Si(C14H29O) (OEt)2],
[(C14H29O) (EtO)2Si(CH2)3]Sx[(CH2)3Si(C14H29O)2(OEt)] ,
[ (C14H29O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C14H29O) 2 (OEt) ] ,
[ (C14H29O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C14H29O) 2 (OEt) ] ,
[ (C14H29O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C14H29O) 3] ,
[ (C14H29O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C14H29O) 3] ,
[ (C14H29O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C14H29O) 3] ,
(C16H33O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (OEt) 3] ,
[(C16H33O)2(EtO)Si(CH2)3]Sx[ (CH2)3Si(OEt)3] ,
[ (C16H33O) 3Si (CH2) 3] Sx[ (CH2) 3Si (OEt) 3] ,
[ (C16H33O) (EtO)2Si(CH2)3]Sx[ (CH2)3Si(C16H33O) (OEt)2] ,
[ (C16H33O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) (OEt) 2] ,
[ (C16H33O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) (OEt) 2] ,
[ (C16H33O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) 2 (OEt) ] ,
[ (C16H33O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) 2 (OEt) ] ,
[ (C16H33O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) 2 (OEt) ] ,
[ (C16H33O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) 3] ,
[ (C16H33O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C16H33O) 3] ,
[(C16H33O)3Si(CH2)3]Sx[(CH2)3Si(C16H33O)3],
(C18H37O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (OEt) 3] ,
[ (C18H37O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (OEt) 3] ,
[(C18H37O)3Si(CH2)3]Sx[(CH2)3Si(OEt)3],
[(C18H37O) (EtO)2Si(CH2)3]Sx[(CH2)3Si(C18H37O) (OEt)2],
[ (C18H37O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) (OEt) 2] ,
[ (C18H37O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) (OEt) 2] ,
[ (C18H37O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) 2 (OEt) ] ,
[ (C18H37O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) 2 (OEt) ] ,
[ (C18H37O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) 2 (OEt) ] ,
[ (C18H37O) (EtO) 2Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) 3] ,
[ (C18H37O) 2 (EtO) Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) 3] ,
[ (C18H37O) 3Si (CH2) 3] Sx[ (CH2) 3Si (C18H37O) 3] ,
or generally
[(CyHyx+1O) (R)2Si(CH2)3]Sx[(CH2)3Si(R)3] ,
[(CyH2y+1O)2(R)Si(CH2)3]Sx[(CH2)3Si(R)3] ,
[(CyH2y+1O)3Si(CH2)3]Sx[(CH2)3Si(R)3],
[(CyH2y+1O) (R)2Si(CH2)3]Sx[(CH2)3Si(CyH2y+1O) (R)2],
[ (CyH2y+1O) 2 (R) Si (CH2) 3] Sx[ (CH2) 3Si (CyH2y+1O) (R) 2] ,
[(CyH2y+1O)3Si(CH2)3]Sx[ (CH2)3Si(CyH2y+10) (R)2] ,
[(CyH2y+1O) (R)2Si(CH2)3]Sxf (CH2)3Si(CyH2y+10)2(R)] ,
[ (CyH2y+1O) 2 (R) Si (CH2) 3] Sx [ (CH2) 3Si (CyH2y+1O) 2 (R) ] ,
[(CyH2y+1O)3Si(CH2)3]Sx[(CH2)3Si(CyH2y+1O)2(R)] ,
[ (CyH2y+1O) (R)2Si(CH2)3]Sx[ (CH2)3Si(CyH2y+1O)3] ,
[ (CyH2y+1O) 2 (R) Si (CH2) 3] Sx[ (CH2) 3Si (CyH2y+1O) 3] or
[(CyH2y+1O)3Si(CH2)3]Sx[(CH2)3Si(CyH2y+1O)3] ,
where x = 1-14, y = 10-24 and R = (MeO) or/and (EtO), or
mixtures of the individual silanes cited above.
Compounds such as are described in DE 198 44 607 can also
be used as the silane.
An organosilicon compound or mixtures of organosilicon
compounds having the general formula (II)
X1X2X3Si-A-S-SiR1R2R3 (II)
can be used as the silane, in which formula
X1, x2, X3 and A mutually independently have the same
meaning as in formula (I),
R1, R2, R3 are each mutually independent from one another
and denote (C1-C16) alkyl, preferably (C1-C4) alkyl,
particularly preferably methyl and ethyl,
(C1-C16) alkoxy, preferably (C1-C4) alkoxy, particularly
preferably methoxy and ethoxy,
(C1-C16) haloalkyl, aryl, (C7-C16) aralkyl, -H, halogen or
X1X2X3Si-A-S-.
The following compounds can be used for example as the
silane having the general formula (II):
(EtO)3-Si-(CH2)3-S-Si(CH3)3, [(EtO)3-Si-(CH2)3-S]2Si(CH3)2,
[(EtO)3-Si-(CH2)3-S]3Si(CH3) , [ (EtO)3-Si-(CH2)3-S]2Si(OEt)2,
[ (EtO) 3-Si- (CH2) 3-S] 4Si, (EtO) 3-Si- (CH2) 3-S-Si (OEt) 3,
(MeO) 3-Si- (CH2) 3-S-Si (C2H5) 3 , [ (MeO) 3-Si- (CH2) 3-S] 2Si (C2H5) 2,
[(MeO)3-Si- (CH2)3-S]3Si(CH3) , [MeO) 3-Si- (CH2) 3-S] 2Si (OMe) 2,
[ (MeO) 3-Si- (CH2) 3-S] 4Si, (MeO) 3-Si- (CH2) 3-S-Si (OMe) 3,
(EtO)3-Si-(CH2)2-CH(CH3)-S-Si(CH3)3,
(EtO)3-Si-(CH2)2-CH(CH3)-S-Si(C2H5)3,
(EtO) 3-Si- (CH2) 2-CH (CH3) -S-Si (C6H5) 3 or
(EtO) 3-Si- (CH2) 2 (P-C6H4) - S-Si (CH3) 3 .
An organosilicon compound or mixtures of organosilicon
compounds having the general formula (III)
X1X2X3Si-Alk (III)
can be used as the silane, in which formula
X1, X2 and X3 each mutually independently have the same
meaning as in formula (I) and
Alk is a straight-chain, branched or cyclic (C1-C18) alkyl,
for example methyl, ethyl, n-propyl, n-butyl, n-pentyl,
n-hexyl, isopropyl or tert.-butyl, (C1-C5) alkoxy, for
example methoxy, ethoxy, propoxy, butoxy, isopropoxy,
isobutoxy, t-butoxy or pentoxy, halogen, for example
fluorine, chlorine, bromine or iodine, hydroxy, thiol,
nitrile, (C1-C4) haloalkyl, -N02, (C1-C8) thioalkyl, -NH2,
-NHR1, -NR1R2, NH(SiX1X2X3) , alkenyl, allyl, vinyl, aryl or
(C7-C16) aralkyl.
The term alkenyl can include the vinyl group as well as
straight-chain, branched or cyclic fragments, which can
contain one or more carbon double bonds.
The term cyclic alkyl or alkenyl fragments can include
both monocyclic and bicyclic or polycyclic structures, as
well as cyclic structures provided with alkyl
substituents, for example norbornyl, norbornenyl, ethyl
norbornyl, ethyl norbornenyl, ethyl cyclohexyl, ethyl
cyclohexenyl or cyclohexyl cyclohexyl groups.
Aryl can be understood to include phenyls, biphenyls or
other benzenoid compounds, which are optionally
substituted with (C1-C3) alkyl, (C1-C3) alkoxy, halogen,
hydroxy or with heteroatoms, such as NR1R2OR1, PR1R2R3, SH
or SR1.
The following compounds can be used for example as the
silane having the general formula (III):
(C12H25O)3-Si- (CH2)16-H,(C14H29O)3-Si- (CH2)16-H,
(C16H33O)3-Si- (CH2)16-H, (C18H37O)3-Si- (CH2) 16-H,
(EtO)3-Si-(CH2)3-H, (MeO)3-Si-(CH2)3-H, (EtO) 3-Si-C (CH3)3,
(MeO)3-Si-C(CH3)3, (EtO)3-Si-(CH2)8-H, (MeO) 3-Si-(CH2) 8-H,
(EtO)3-Si-(CH2)16-H, (MeO)3-Si-(CH2)16-H, (Me)3Si-(OMe) ,
( (Et)3Si-(OMe) , (C3H7)3Si-(OMe) , (C6H5)3Si- (OMe) ,
(Me)3Si-(OEt) , ( (Et)3Si-(OEt) , (C3H7)3Si-(OEt) ,
(C6H5)3Si-(OEt), (Me)3Si-(OC3H7), (Et) 3Si-(OC3H7) ,
(C3H7)3Si-(OC3H7), (C6H5)3Si-(OC3H7) , (Me)3SiCl, (Et)3SiCl,
(C3H7)3SiCl, (C6H5)3SiCl, Cl3-Si-CH2-CH=CH2, (MeO) 3-Si-CH2-
CH=CH2, (EtO)3-Si-CH2-CH=CH2, (EtO)3-Si-CH2-CH=CH2 Cl3-Si-
CH=CH2, (MeO)3-Si-CH=CH2, (EtO) 3-Si-CH=CH2, (Me3Si) 2N-C (O)-H
or (Me3Si)2N-H.
An organosilicon compound or a mixture of organosilicon
compounds having the general formulae (IV) or (V)
[ [ (ROC (=0) ) p- (G) j] k-Y-S] r-G- (SiX1X2X3) s (IV)
[(X1X2X3Si)g-G]a-[Y-[S-G-SiX1X2X3]b]c (V)
can be used as the silane,
in which formulae Y represents a polyvalent species
(Q)ZD(=E), whereby the following is true:
p is 0 to 5, r is 1 to 3, z is 0 to 2, q is 0 to 6, a is 0
to 7, b is 1 to 3, j is 0 to 1, but if p = 1 it can also
commonly be 0, c is 1 to 6, preferably 1 to 4, t is 0 to
5, s is 1 to 3, k is 1 to 2, under the proviso that
(1) if (D) is a carbon, sulfur or sulfonyl, a + b = 2 and
k = 1,
(2) if (D) is a phosphorus atom, a + b = 3 provided that
c = 1 and b = 1, whereby a = c + 1,
(3) if (D) is a phosphorus atom, k = 2,
Y represents a polyvalent species (Q)ZD(=E), preferably
-C(=NR)-, -SC(=NR)-, -SC(=O)-, (-NR)C(=O)-, (-NR)C(=S)-,
-0C(=0)-, -OC(=S)-, -C(=0)-, -SC(=S)-, -C(=S)-, -S(=0)-,
-S(=0)2-, -0S(=0)2-, (-NR)S(=O)2-, -SS(=O)-, -0S(=0)-,
(NR)S(=O)-, -SS(=O)2-, (-S)2P(=O)-, -(-S)P(=O)-,
-P(=0)(-)2, (-S)2P(=S)-, -(-S)P(=S)-, -P(=S)(-)2,
(-NR)2P(=O)-, (-NR)(-S)P(=O)-, (-0)(-NR)P(=O)-,
(-0)(-S)P(=O)-, (-0)2P(=0)-, -(-0)P(=0)-, -(-NR)P(=0)-,
(-NR)2P(=S)-, (-NR)(-S)P(=S)-, (-0)(-NR)P(=S)-,
(-0)(-S)P(=S)-, (-O)2P(=S)-, -(-O)P(=S)- or -(-NR)P(=S)-,
in each of these groups the atom (D) is doubly bonded to
the heteroatom (E), which in turn is bonded to the sulfur
atom (S), which is coupled to the silicon atom (Si) by
means of a group (G),
R1 mutually independently denotes H,
a straight, cyclic or branched alkyl chain, preferably
(C1-C18) alkyl, particularly preferably (C1-C4) alkyl,
optionally alkyl chains containing unsaturated components
such as double bonds (alkenes), triple bonds (alkynes) or
alkyl aromatics (aralkyl) or aromatics and displaying the
same meanings as in formula (II),
G independently of the other substituents denotes
hydrogen, a straight, cyclic or branched alkyl chain with
(C1-C18) , whereby the alkyl chains can optionally contain
an unsaturated component, such as double bonds (alkenes),
triple bonds (alkynes) or alkyl aromatics (aralkyl) or
aromatics,
if p = 0 in formula (IV), G is preferably hydrogen (H),
G does not correspond to the structure of an a, b-
unsaturated fragment that is bonded to the Y fragment in
such a way that an a, p-unsaturated thiocarbonyl fragment
is formed,
X1, X2 and X3 each mutually independently has the meaning
as in formula (I).
An index p of 0 to 2 is preferred, whereby x1, X2 or X3 is
an R0- or RC(=O)O-. A fragment with p = 0, X1, X2 or X3 =
ethoxy and with G = alkyl skeleton or substituted alkyl
skeleton with C3 to C12 is particularly preferred. At least
one X does not have to be equal to -R1.
In (Q)2D(=E) Q can be oxygen, sulfur or (-NR-), D can be
carbon, sulfur, phosphorus or sulfonyl, E can be oxygen,
sulfur or (=NR1) .
Preferred examples of the function (-YS-) in formulae (IV)
and (V) are:
thiocarboxylate esters -C(=O)-S-, dithiocarboxylates
-C(=S)-S-, thiocarbonate esters -0-C(=O)-S-,
dithiocarbonate esters -S-C(=O)-S- and -O-C(=S)-S-,
trithiocarbonate esters -S-C(=S)-S-, dithiocarbamate
esters -N-C(=S)-S-, thiosulfonate esters -S(=O)2-S-,
thiosulfate esters -O-S(=O)2-S-, thiosulfamate esters
(-N-)S(=O)2-S-, thiosulfinate esters -C-S(=O)-S-,
thiosulfite esters -O-S(=O)-S-, thiosulfimate esters
N-S(=O)-S-, thiophosphate esters P(=O) (O-)2(S-),
dithiophosphate esters P(=O)(O-)(S-)2 or P(=S)(O-)a(S-),
trithiophosphate esters P(=O)(S-)3 or P(=S)(O-)(S-)2,
tetrathiophosphate esters P(=S)(S-)3, thiophosphamate
esters -P(=O)(-N-)(S-), dithiophosphamate esters
-P(=S)(-N-)(S-, thiophosphoramidate esters
(-N-)P(=O)(O-)(S- ), dithiophosphoramidate esters
(-N-)P(=O)(S-)2 or (-N-)P(=S)(O-)(S-) or
trithiophosphoramidate esters (-N-)P(=S)(S-)2.
The following compounds can be used for example as the
silane having the general formula (IV) or (V):
2-triethoxysilyl-l-ethyl thioacetate, 2-trimethoxysilyl-l-
ethyl thioacetate, 2-(methyldimethoxysilyl)-1-ethyl
thioacetate, 3-trimethoxysilyl-l-propyl thioacetate,
triethoxysilyl methyl thioacetate, trimethoxysilyl methyl
thioacetate, triisopropoxysilyl methyl thioacetate, methyl
diethoxysilyl methyl thioacetate, methyl dimethoxysilyl
methyl thioacetate, methyl diisopropoxysilyl methyl
thioacetate, dimethyl ethoxysilyl methyl thioacetate,
dimethyl methoxysilyl methyl thioacetate, dimethyl
isopropoxysilyl methyl thioacetate,
2-triisopropoxysilyl-l-ethyl thioacetate, 2-(methyl
diethoxysilyl)-1-ethyl thioacetate, 2-(methyl
diisopropoxysilyl)-1-ethyl thioacetate,
2-(dimethylethoxysilyl)-1-ethyl thioacetate, 2-(dimethyl
methoxysilyl)-1-ethyl thioacetate, 2-(dimethyl
isopropoxysilyl)-1-ethyl thioacetate,
3-triethoxysilyl-1-propyl thioacetate,
3-triisopropoxysilyl-l-propyl thioacetate, 3-methyl
diethoxysilyl-1-propyl thioacetate, 3-methyl
dimethoxysilyl-1-propyl thioacetate, 3-methyl
diisopropoxysilyl-1-propyl thioacetate,
1-(2-triethoxysilyl-l-ethyl)-4-thioacetyl cyclohexane,
1-(2-triethoxysilyl-l-ethyl)-3-thioacetyl cyclohexane,
2-triethoxysilyl-5-thioacetyl norbornene,
2-triethoxysilyl-4-thioacetyl norbornene,
2-(2-triethoxysilyl-l-ethyl)-5-thioacetyl norbornene,
2-(2-triethoxysilyl-l-ethyl)-4-thioacetyl norbornene, 1-
(1 -oxo-2-thia-5-triethoxysilylpentyl) benzoic acid,
6-triethoxysilyl-l-hexyl thioacetate,
1-triethoxysilyl-5-hexyl thioacetate, 8-triethoxysilyl-l-
octyl thioacetate, l-triethoxysilyl-7-octyl thioacetate,
6-triethoxysilyl-1-hexyl thioacetate,
l-triethoxysilyl-5-octyl thioacetate, 8-trimethoxysilyl-l-
octyl thioacetate, l-trimethoxysilyl-7-octyl thioacetate,
10-triethoxysilyl-l-decyl thioacetate,
l-triethoxysilyl-9-decyl thioacetate,
1-triethoxysilyl-2-butyl thioacetate,
1-triethoxysilyl-3-butyl thioacetate,
l-triethoxysilyl-3-methyl-2-butyl thioacetate,
1-triethoxysilyl-3-methyl-3-butyl thioacetate,
3-trimethoxysilyl-1-propyl thiooctoate,
3-triethoxysilyl-l-propyl thiopalmitate,
3-triethoxysilyl-l-propyl thiooctoate,
3-triethoxysilyl-l-propyl thiobenzoate,
3-triethoxysilyl-l-propyl thio-2-ethyl hexanoate, 3-methyl
diacetoxysilyl-1-propyl thioacetate, 3-triacetoxysilyl-l-
propyl thioacetate, 2-methyl diacetoxysilyl-1-ethyl
thioacetate, 2-triacetoxysilyl-l-ethyl thioacetate,
1-methyl diacetoxysilyl-1-ethyl thioacetate or
1-triacetoxysilyl-l-ethyl thioacetate.
Compounds having the formulae IV and V are also described
in EP0958298 or WO9909036.
An organosilicon compound or a mixture of organosilicon
compounds having the general formula (VI)
X1X2X3Si-A-Sub (VI)
can be used as the si lane, whereby X1, X2, X3 and A, each
mutually independently, have the meaning according to
formula (I) and Sub is
-SH, -NH2, -NH(A-SiX1X2X3), -N(A-SiX1X2X3) 2, 0-C (0)-CMe=CH2
or -SCN.
The following compounds can be used for example as the
silane having the general formula (VI):
(MeO)3Si-(CH2)3-SH, (MeO)3Si-(CH2) 3-NH2, (MeO)3Si-(CH2)3-SCN,
(MeO)3Si-(CH2 3-0-C(0)CMe=CH2,
(EtO)3Si-(CH2)3-NH2, (EtO)3Si-(CH2)3-SH, (EtO) 3Si- (CH2)3-SCN,
(EtO)3Si- (CH2) 3-0-C (0) CMe=CH2,
(C3H7O) 3Si- (CH2) 3-SH, (C3H7O) 3Si- (CH2) 3-SCN,
(C3H7O)3Si-(CH2)3-O-C(O)CMe=CH2, (C3H7O) 3Si-(CH2) 3-NH2,
[(MeO)3Si-(CH2)3-]2NH, [(EtO)3Si-(CH2)3-]2NH, [(C3H7O)3Si-
(CH2)3-]2NH,
or
(C12H25O) 2 (MeO) -Si- (CH2) 3-SH, (C12H25O) 2 (EtO) -Si- (CH2) 3-SH,
(C12H25O)2(C14H29O)-Si-(CH2)3-SH, (C12H25O) 2 (C16H33O)-Si-(CH2) 3-
SH, (C12H25O) 2 (C18H37O) -Si- (CH2) 3-SH,
(C14H29O) 2 (MeO) -Si- (CH2) 3-SH, (C14H29O) 2 (EtO) -Si- (CH2) 3-SH,
(C14H29O) 2 (C12H25O) -Si- (CH2) 3-SH, (C14H29O) 2 (C16H33O) -Si- (CH2) 3-
SH, (C14H29O) 2 (C18H37O) -Si- (CH2) 3-SH, (C16H33O) 2 (MeO) -Si- (CH2) 3-
SH, (C16H33O) 2 (EtO) -Si- (CH2) 3-SH, (C16H33O) 2 (C12H25O) -Si- (CH2) 3-
SH, (C16H33O) 2 (C14H29O) -Si- (CH2) 3-SH,
(C16H33O) 2 (C18H37O) -Si- (CH2) 3-SH, (C18H37O) 2 (MeO) -Si- (CH2) 3-SH,
(C18H37O) 2 (EtO) -Si- (CH2) 3-SH, (C18H37O) 2 (C12H25O) -Si- (CH2) 3-SH,
(C18H37O) 2 (C14H29O) -Si- (CH2) 3-SH, (C18H37O) 2 (C16H33O) -Si- (CH2) 3-
SH,
or
(C12H25O) 2 (MeO) -Si- (CH2) 3-NH2, (C12H25O) 2 (EtO) -Si- (CH2) 3-NH2,
(C12H25O) 2 (C14H29O) -Si- (CH2) 3-NH2, (C12H25O) 2 (C16H33O) -Si- (CH2) 3-
NH2, (C12H25O)2(C18H37O)-Si-(CH2)3-NH2,
(C14H29O) 2 (MeO) -Si- (CH2) 3-NH2, (C14H29O) 2 (EtO) -Si- (CH2) 3-NH2,
(C14H29O) 2 (Ci2H25O) -Si- (CH2) 3-NH2, (C14H29O) 2 (C16H33O) -Si- (CH2) 3-
NH2, (C14H29O)2(C18H37O)-Si-(CH2)3-NH2,
(C16H33O) 2 (MeO) -Si- (CH2) 3-NH2, (C16H33O) 2 (EtO) -Si- (CH2) 3-NH2,
(C16H33O) 2 (C12H25O) -Si- (CH2) 3-NH2, (C16H33O) 2 (C14H29O) -Si- (CH2) 3-
NH2, (C16H33O)2(C18H37O)-Si-(CH2)3-NH2,
(C18H37O)2(MeO)-Si-(CH2)3-NH2, (C18H37O) 2 (EtO)-Si-(CH2) 3-NH2,
(C18H37O)2(C12H25O)-Si-(CH2)3-NH2, (C18H37O) 2 (C14H29O)-Si-(CH2) 3-
NH2, (C18H37O)2(C16H33O)-Si-(CH2)3-NH2,
or
(C12H25O) 2 (C14H29O) -Si- (CH2) 3-SCN, (C12H25O) 2 (C16H33O) -Si- (CH2) 3-
SCN, (C12H25O)2(C18H37O)-Si-(CH2)3-SCN,
(C14H29O) 2 (C12H25O) -Si- (CH2) 3-SCN, (C14H29O) 2 (C16H33O) -Si- (CH2) 3-
SCN, (C14H29O)2(C18H37O)-Si-(CH2)3-SCN,
(C16H33O) 2 (C12H25O) -Si- (CH2) 3-SCN, (C16H33O) 2 (C14H29O) -Si- (CH2) 3-
SCN, (C16H33O)2(C18H37O)-Si-(CH2) 3-SCN,
(C18H37O) 2 (C12H25O) -Si- (CH2) 3-SCN, (C18H37O) 2 (C14H29O) -Si- (CH2) 3-
SCN, (C18H37O) 2 (C16H33O) -Si- (CH2) 3-SCN,
or
(C12H25O) 2 (MeO) -Si- (CH2) 3-0-C (0) CMe=CH2,
(C12H25O) 2 (EtO) -Si- (CH2) 3-0-C (0) CMe=CH2,
(Ci4H29O) 2 (MeO) -Si- (CH2) 3-0-C (0) CMe=CH2,
(C14H29O)2(EtO)-Si-(CH2)3-O-C(O)CMe=CH2,
(C16H33O) 2 (MeO) -Si- (CH2) 3-0-C (0) CMe=CH2,
(C16H33O) 2 (EtO) -Si- (CH2) 3-0-C (0) CMe=CH2,
(C18H37O) 2 (MeO) -Si- (CH2) 3-O-C (O) CMe=CH2,
(C18H37O) 2 (EtO) -Si- (CH2) 3-O-C (0) CMe=CH2,
or
[(CyH2y+1O) (EtO)2Si(CH2)3]-NH2, [ (CyH2y+1O) 2 (EtO) Si (CH2) 3]-NH2,
[(CyH2y+1O) (EtO)2Si(CH2)3]-SH/ [ (CyH2y+1O) 2 (EtO) Si (CH2) 3] -SH,
[(CyH2y+1O) (EtO)2Si(CH2)3]-SCN, [ (CyH2y+1O) 2 (EtO) Si (CH2) 3]-SCN,
[ (CyH2y+1O) (EtO)2Si (CH2) 3] -0-C (0) -CMe=CH2,
[(CyH2y+1O)2(EtO)Si(CH2)3]-O-C(O)-CMe=CH2, where y = 10-24,
or mixtures of the aforementioned silanes.
Oligomers, in other words oligosiloxanes and
polysiloxanes, or cooligomers of silanes having the
general formula (I)-(VI), or mixtures thereof, can be used
as the silane. The siloxanes can be obtained by
oligomerisation or cooligomerisation of the corresponding
silane compounds having the general formulae (I)-(VI) by
addition of water and of additives known to the person
skilled in the art in this area.
Oligomeric silanes are described for example in EP 652 245
Bl, EP 0 700 951 Bl, EP 0 978 525 A2 and DE 199 29 021 Al.
Mixtures of silanes can also be used as the silane within
the meaning of the present invention for the modification
of fillers, for example mixtures of silanes having the
general formula (I)-(VI) or mixtures of the oligomeric or
polymeric siloxanes of silanes having the general formula
(I)-(VI) or mixtures of silanes having the general formula
(I)-(VI) with mixtures of the oligomeric or polymeric
siloxanes of silanes having the general formula (I)-(VI).
A natural and/or synthetic filler can be used as the
untreated microbeaded or microgranular oxidic or siliceous
filler.
The microbeaded or microgranular oxidic or siliceous
filler can be compatible with the rubbers and display the
fine-particle character and reinforcing effect in the
polymer matrix that is necessary for this application.
Silicate, for example kaolin, mica, kieselguhr,
diatomaceous earth, talc, wollastonite or clay, as well as
silicates inter alia in the form of glass beads, ground
glass chips (glass powder), glass fibres or glass cloths,
can be used as the natural, siliceous filler.
All types of metal oxides, for example aluminium oxide,
aluminium hydroxide or trihydrate, zinc oxide, boron
oxides, magnesium oxides, as well as transition metal
oxides, such as titanium dioxide, can be used as oxidic
fillers.
In addition, aluminium silicates, silicates, zeolites,
precipitated silicas with BET surface areas (measured with
gaseous nitrogen) of 1 to 1000 m2/g, preferably to
300 m2/g, can be used as the oxidic or siliceous filler.
By way of example, the precipitated silica Ultrasil 7005
sold by Degussa AG as well as the silica Hi-Sil® 210 sold
by PPG Industries Inc. and the products Zeosil 1115 MP,
Zeosil 1135 MP, zeosil 1165 MP, Zeosil 1165 MPS or Zeosil
1205 MP sold by Rhodia can be used.
Silicas from other manufacturers that display similar
properties or product characteristics to the silicas
mentioned above or display similar, comparable analytical
data (especially BET surface areas, CTAB surface areas,
BET/CTAB ratio, Sears number, bead fraction or particle
size distributions, shape factors, circle factors and DBP
index), can also be used without any problem to produce
the silane-modified oxidic or siliceous filler according
to the invention.
Compounds that are gaseous under normal temperature and
pressure conditions and that are suitable as a reaction
matrix for the silane/filler mixtures can be used as the
compressed gas. For example, carbon dioxide, helium,
nitrogen, dinitrogen monoxide, sulfur hexafluoride,
gaseous alkanes with 1 to 5 C atoms (methane, ethane,
propane, n-butane, isobutane, neopentane), gaseous alkenes
with 2 to 4 C atoms (ethylene, propylene, butene), gaseous
alkynes (acetylene, propyne and butyne-1), gaseous dienes
(propadiene) , gaseous fluorocarbons, chlorinated
hydrocarbons and/or chlorofluorocarbons (freons, CHCs,
HCFCs) or substitutes thereof that are used because of
current legislation, or ammonia, as well as mixtures of
these substances, can be used.
Carbon dioxide can preferably be used as the compressed
gas, since it is non-toxic, non-combustible, unreactive
and inexpensive. In addition, the necessary supercritical
conditions or near critical conditions can easily be
achieved as the critical pressure and critical temperature
are only 73 bar and 31°C respectively.
Compressed gases can be defined according to E.Stahl,
K.W.Quirin, D.Gerard, "Verdichtete Gase zur Extraktion und
Raffination", Springer-Verlag, page 12-13. Compressed
gases can be supercritical gases, critical gases or gases
in the liquefied region.
Surprisingly, the use according to the invention of a
compressed gas is extremely advantageous. Commercial
microbeaded or microgranular, oxidic or siliceous fillers
corresponding to the present invention, for example, and
especially silicas, are silanised unexpectedly well, not
only at or adjacent to the surface but also comparatively
homogeneously within a microbead or microgranule.
Due to the high dissolving power and diffusibility, the
low viscosity and the ability of organic silanes or
organic oligomeric or polymeric siloxanes in particular to
permit high diffusion rates in the compressed gas,
compressed gases are surprisingly suitable for
impregnating microporous, mesoporous and macroporous
solids with monomeric or oligomeric silane compounds. The
silane compounds can be transported by the compressed gas
into the pores and channels and onto the so-called "inner
surfaces" of the microbeaded or microgranular porous
fillers. They are then chemically or/and physically bonded
there and immobilised.
Since they are in gaseous form under normal conditions,
compressed gases can advantageously be easily separated
from the filler on completion of its silanisation and in
the case of carbon dioxide in particular they also have
virtually no environmentally hazardous potential, since
they find their way into the natural carbon cycle or can
easily be recycled. That is a significant technical
advantage as compared with known processes, since on the
one hand a homogeneous reaction matrix is assured by the
compressed fluid in the same way as with known organic
solvents yet at the same time a complex removal step; for
example removal of a solvent in vacuo under thermal
loading, can be avoided.
The compressed gas can be pressurised in an air-tight
sealed room or container in which the material to be
treated is located. During this process the pressure can
be increased, generally from atmospheric pressure, to the
operating pressure for the process according to the
invention.
The silanes used can be present in the compressed gas in
undissolved, partially dissolved or wholly dissolved form.
The microbeaded or microgranular, oxidic or siliceous
filler and the silane can first be mixed together or
brought into contact and then mixed or brought into
contact with the gas in compressed form.
The microbeaded or microgranular, oxidic or siliceous
filler can first be mixed together or brought into contact
with the gas in compressed form and then mixed or brought
into contact with the silane.
The silane can first be mixed together or brought into
contact with the gas in compressed form and then mixed or
brought into contact with the corresponding microbeaded or
microgranular, oxidic or siliceous filler.
"Brought into contact" can mean that the cited material is
immersed, wetted or covered and is dissolved or
undissolved, suspended, adsorbed or absorbed.
The "bringing into contact" can be achieved for example in
a container or in a hermetically sealed room into which
the unmodified filler, the silane component and the gas
that can potentially be transformed into the compressed
state are introduced by suitable means.
Contact between the unmodified filler and the silane
component can be achieved here by means of various
technical solutions. This can preferably be achieved using
a suitable mixing unit with an integral liquid metering
device, such as are very familiar to the person skilled in
the art in this area. These can be, by way of example but
not exclusively, mixers such as are supplied by the
companies Drais, Eirich, Forberg, Gericke, Lodige, Ruberg.
The mixing unit can provide a homogeneous, low-abrasion
distribution of the silane used onto the microbeaded or
microgranular, oxidic or siliceous filler. The energy
input can advantageously be low. Tumbling mixers (e.g.
drum mixers) and mixers with rotating tools and low
particle loading (Froude number purpose.
Contact between the homogeneously mixed silane and filler
component and the gas which can potentially be transformed
into the compressed state can be established for example
in a container or in a hermetically sealed room into which
the mixture of filler and silane can be introduced by
suitable means. "Establishing contact" can mean that the
cited material is immersed in the impregnating fluid and
is wetted and covered by it, preferably that the
microbeaded or microgranular, oxidic or siliceous filler
is completely immersed, or that all outer and inner
surfaces of the microbeaded or microgranular, oxidic or
siliceous filler are in contact with the compressed gas.
The solubility of the silane component in the compressed
gas can be dependent on the nature of said gas, on its
pressure and temperature. It can also be modulated and
optimised by varying the pressure and temperature in order
to adjust the physical properties of the compressed gas.
In some cases the concentration of the silane in the
solution used as the reaction medium can influence the
efficiency of the treatment.
In the process according to the invention 10-250 parts by
weight of microbeaded or microgranular, oxidic or
siliceous filler can be reacted with 0.1-50 parts by
weight, preferably 0.5-15 parts by weight, of silane.
In the process according to the invention the pressure,
which is also known as the operating pressure, can
generally be between 1 and 500 bar, preferably between 1
and 200 bar, particularly preferably between 1 and 150
bar.
The temperature (operating temperature) at which the
process can be performed is between 0 and 300°C,
preferably between 0 and 200°C, particularly preferably
between 0 and 13 0°C.
The reaction can be performed in a typical reaction vessel
for high temperature/high pressure reactions or high
pressure extractions.
During the modification the pressure can be kept constant
at various pressure levels for periods of 5-720 min,
preferably 5-240 min, particularly preferably 5-30 min,
and during this time the filler can be immersed or stirred
in the compressed gas or the compressed gas can be passed
through it.
Additives can be added to the microbeaded or
microgranular, oxidic or siliceous filler and/or silane
before the reaction in the compressed gas.
The silane-modified oxidic or siliceous filler can be
brought into contact with additional additives during the
reaction in the compressed gas.
During the reaction of the microbeaded or microgranular,
oxidic or siliceous filler in the compressed gas,
additional additives can be introduced into the incoming
or outgoing stream of compressed gas flowing through the
silane-modified oxidic or siliceous filler.
Ammonia, sulfur dioxide, water, short-chain or long-chain
alcohols, for example methanol, ethanol, propanol,
butanol, dodecanol, tetradecanol, hexadecanol, octadecanol
or other alcohols with molecular weights > 50 g/mol,
short-chain or long-chain polyethers or polyether
alcohols, for example diethylene glycol, triethylene
glycol or others with molecular weights > 100 g/mol,
short-chain or long-chain amines with molecular weights >
50 g/mol, emulsifiers or short-chain or long-chain
silicone oils, for example silicone oils with molecular
weights > 100 g/mol, or mixtures of the aforementioned
compounds, can be used as additives. The silane-modified
oxidic or siliceous filler can come into contact with
additional substances, in addition to the compressed gas
or compressed gas mixtures, during the modification
reaction.
The microbeaded or microgranular, oxidic or siliceous
filler mixed with the silane can be continuously
circulated with a suitable agitator in the high-pressure
unit or high-pressure vessel. The stirring speed can be
adjusted to the prevailing temperature and pressure.
Lifting agitators, paddle agitators, straight-arm paddle
agitators, perforated paddle agitators, cross-arm paddle
agitators, anchor agitators, gate agitators, straight-
blade turbines, propeller agitators, screw mixers, turbine
mixers, disk agitators, planetary-type mixers, centrifugal
mixers or impeller agitators can be used as the agitator.
The agitator in the high-pressure vessel can operate at 1-
100, preferably 1-50 revolutions, strokes or circulations
per minute.
The microbeaded or microgranular, oxidic or siliceous
filler mixed with a silane can be continually wetted
during the modification reaction by a compressed gas
passing through it, without being circulated in the high-
pressure vessel or being mixed together any more by
agitators.
Following surface modification the silane-modified oxidic
or siliceous filler can undergo an evacuation or pressure
release stage with separation of the compressed gas and
the added additives or part of the added additives from
the end product.
The evacuation or pressure release stage can be performed
in a time of between 1 min and 180 min, preferably between
1 min and 120 min, particularly preferably between 1 min
and 60 min.
The evacuation or pressure release stage can be performed
at temperatures between 1 and 3 00°C, preferably between 1
and 200°C, particularly preferably between 1 and 150°C,
and most particularly preferably at temperatures between 1
and 130°C.
The silane-modified oxidic or siliceous filler according
to the invention can undergo an additional compacting or
processing stage.
The silane-modified oxidic or siliceous filler can be used
in paints, lacquers, printing inks, films, coatings,
adhesives and lubricants, cosmetics, toothpastes, building
auxiliary materials or as a filler in vulcanisable
rubbers, silicones or plastics.
The invention also provides rubber compounds that are
characterised in that they contain rubber, the silane-
modified oxidic or siliceous filler according to the
invention, optionally precipitated silica and/or carbon
black and/or other rubber auxiliary substances.
Natural rubber or synthetic rubbers can be used to produce
rubber compounds according to the invention. Preferred
synthetic rubbers are described for example in W. Hofmann,
Kautschuktechnologie, Genter Verlag, Stuttgart 1980. They
include inter alia polybutadiene (BR), polyisoprene (IR),
styrene/butadiene copolymers with styrene contents of 1 to
60, preferably 5 to 50 wt.% (E- or S-SBR), isobutylene/
isoprene copolymers (IIR), butadiene/acrylonitrile
copolymers with acrylonitrile contents of 5 to 60,
preferably 10 to 50 wt.% (NBR), chloroprene (CR),
ethylene/propylene/diene copolymers (EPDM), and mixtures
of these rubbers.
The rubber compounds according to the invention can
contain other rubber auxiliary products, such as for
example reaction accelerators and retarders, antioxidants,
stabilisers, processing aids, plasticisers, waxes, metal
oxides and activators, such as triethanolamine,
polyethylene glycol or hexane triol, organically modified
silanes and other rubber auxiliary products known to the
rubber industry.
The rubber compound can additionally contain alkyl silanes
or/and silicone oils.
The rubber auxiliary substances can be used in
conventional quantities, which are governed inter alia by
the intended application. Conventional quantities are for
example quantities of 0.1 to 50 wt.% relative to rubber.
Sulfur, organic sulfur donors or radical formers can serve
as crosslinking agents. The rubber compounds according to
the invention can additionally contain vulcanisation
accelerators.
Examples of suitable vulcanisation accelerators are
mercaptobenzothiazoles, sulfenamides, guanidines,
thiurams, dithiocarbamates, thio ureas and thiocarbonates.
The vulcanisation accelerators and crosslinking agents can
be used in quantities of 0.1 to 10 wt.%, preferably 0.1 to
5 wt.%, relative to rubber.
The rubbers can be mixed with the silane-modified oxidic
or siliceous filler according to the invention, optionally
with precipitated silica and/or carbon black and/or other
rubber auxiliary substances in conventional mixing units,
such as rolls, internal mixers and compounding extruders.
Such rubber compounds can conventionally be produced in
internal mixers, whereby the rubbers, the silane-modified
oxidic or siliceous filler according to the invention,
optionally the precipitated silica and/or carbon black
and/or other rubber auxiliary substances are first
incorporated at 100 to 170°C in one or more successive
thermomechanical mixing stages. The sequence in which the
individual components are added and the time at which they
are added can have a decisive impact on the compound
properties obtained. The rubber compound thus obtained can
then be mixed with the crosslinking chemicals by known
means in an internal mixer or on a roll at 40-110°C and
processed to form what is known as an unvulcanised mix for
the subsequent process steps, such as moulding and
vulcanisation for example.
Vulcanisation of the rubber compounds according to the
invention can take place at temperatures of 80 to 200°C,
preferably 130 to 180°C, optionally under a pressure of 10
to 200 bar.
The rubber compounds according to the invention are
suitable for producing rubber mouldings, for example for
the production of pneumatic tyres for cars and lorries,
tyre treads for cars and lorries, tyre components for cars
and lorries, such as e.g. sidewall, liner and carcass,
cable sheathing, hoses, drive belts, conveyor belts, roll
coverings, bicycle and motor cycle tyres and components
thereof, shoe soles, sealing rings, profiles and damping
elements.
In comparison to purely physical mixtures, for example of
bis-(3-triethoxysilylpropyl) tetrasulfane with silica
(US-PS 4,076,550), the silane-modified oxidic or siliceous
fillers according to the invention display the advantage
of good storage stability and hence performance stability.
In addition, the fillers according to the invention
display a considerably lower content of potentially
releasable alcohols, for example methanol or ethanol, than
physical mixtures of silanes with fillers, are more
readily dispersible and overall display better processing
characteristics for users in the rubber processing
industry (lower dust content, homogeneous compounding,
reduction in mixing stages and mixing times, compounds
with stable properties after the first mixing stage).
In comparison to known silane-modified fillers, for
example bis-(3-triethoxysilylpropyl) tetrasulfane on
silica (VP Coupsil 8108 from Degussa), the silane-modified
oxidic or siliceous fillers according to the invention
display the advantage of better storage stability and
hence better performance stability. In addition, the
fillers according to the invention display in comparison a
considerably lower content of potentially releasable
alcohol, generally ethanol, are more readily dispersible
and overall display better processing characteristics for
users in the rubber processing industry (lower dust
content, homogeneous compounding, reduction in mixing
stages and mixing times). Fewer volatile organic compounds
(VOCs) are released during storage.
As compared with the in-situ method and the untreated
filler that this method requires, the silane-modified
oxidic or siliceous fillers according to the invention
have the advantages of an improved water content in the
treated filler, a lower moisture absorption and a higher
compacted bulk weight, better flow properties and a higher
bulk density compared with the untreated filler.
During the mixing process for the in-situ method a
chemical reaction must be performed in which optimum
process control is required and as a result of which
considerable amounts of alcohol are liberated during the
silanisation reaction. They subsequently escape from the
mixture, thereby leading to problems in the exhaust air.
This is reduced or avoided by the use of the silane-
modified oxidic or siliceous fillers according to the
invention.
Microbeaded or microgranular materials mostly have
elevated bulk densities, which has a positive impact on
the cost effectiveness of transporting the raw material
and product. In comparison to powdered silicas, the
silanised microbeaded or microgranular fillers according
to the invention have similarly advantageous flow and
conveying properties to the microbeaded or microgranular
fillers used as the starting material.
Examples:
Examples for the production of silane-modified oxidic or
siliceous fillers according to the invention
The experiments cited below are performed in a high-
pressure extraction unit for solids with an autoclave
volume of 50 1.
8 kg of Ultrasil 7005 precipitated silica (Degussa AG;
analytical properties: BET = 185 m2/g according to ISO
5794/Anntex D, CTAB surface area = 173 m2/g, loss on drying
= 5.5 wt.% (din ISO787-2), are physically precoated and
mixed together with 640 g Si69 {Degussa AG? bis-
(triethoxysilylpropyl tetrasulfane)) in a Ruberg mixer, In
seme experiments additional amounts of. water are then
sprayed onto the mixture of silica and silane.
The silica that is physically precoated with Si69 is
introduced into a charging vessel (volume 35 1), which is
sealed at the top and bottom with sintering plates. The
completely full charging vessel is placed in the autoclave
of a high-pressure extraction unit (fixed bed), The
autoclave is pressurised using a high-pressure diaphragm
pump and defined quantities of carbon dioxide, Which is
supplied by a high-pressure pump, are passed through at
the pressures and temperatures set out in Tables 1-5 for
fixed times. Primary reaction refers to the chemical
and/or physical immobilisation of the silane on tne
filler. Extraction refers to the partial/complete
hydrolysis of the silane and removal of the alcohol. In
some examples (Tables 4 and 5) a specific amount of water
is metered into the stream of CO2 before it enters the
autoclave. In addition, in the examples in Table 5,
pressure pulses of between 60 and 100 bar are generated to
improve the distribution of the silane on the surface of
the silica. After the fixed bed extractor the loaded
carbon dioxide is transferred to a separator tank in which
it is converted into gaseous form by pressure reduction
and/or temperature increase, whereby the solubility for
the constituents of the fluid (e.g. extracted ethanol) is
reduced and they are largely separated out as a result.
After the separator tank the gaseous carbon dioxide is
condensed by a condenser and passed to a buffer vessel,
from which it can be drawn in again by the high-pressure
pump and used for extraction (cyclic process).
In examples 6 to 9 (Table 2) and 10 to 15 (Table 3) the
carbon dioxide under the cited pressure and temperature
conditions is not transferred to the separator tank but
instead is circulated for a certain time by a bypass high-
pressure pump, whilst maintaining pressure and
temperature, by conveying it in a loop directly back to
the autoclave. The stream is only transferred to the
separator tank under the cited conditions - as shown in
Tables 2 + 3 - to carry out the extraction.
To demonstrate that the throughput direction for
production of the filler according to the invention can be
varied at will, in Examples 10 to 15 (Table 3) the
throughput direction for the carbon dioxide is split, in
other words in the cited ratios the carbon dioxide is
passed through the autoclave alternately from below and
from above, whereby the direction of flow, the throughput
of carbon dioxide and the pressure and temperature
conditions, as shown in Table 3, are maintained.
The Sears numbers are determined by reference to G.W.
Sears, Analyt. Chemistry 12 (1956) 1982 according to the
following instructions:
Before titration the filler is ground in a mill, whereby
it is homogenised and crushed.
60 ml of methanol are added to 2.5 g of the sample thus
obtained in a 250 ml titration vessel and as soon as the
solid is completely wetted a further 40 ml of water are
added to the suspension.
The suspension is dispersed for 30 sec with an agitator
(Ultra-Turrax) and then diluted with a further 100 ml of
water. The suspension is heated to 25°C for at least 20
minutes.
Titration is performed as follows on a titroprocessor
with a pH electrode (e.g. DL 67, Mettler Toledo with a
DG 111 SC electrode):
- first stir for 120 sec;
- adjust the suspension to pH 6 with 0.1 N potassium
hydroxide solution or hydrochloric acid;
- add 20 ml NaCl solution (250 g/1);
- titrate with 0.1 N KOH from pH 6 to pH 9;
- the result is converted to 5 g silica, i.e. to a
consumption of 0.1 N KOH in ml per 5 g silica, in order
to reach pH 9 from pH 6.
The present determination is a further development, more
accurate account and improvement of the method described
in G.W. Sears, Analyt. Chemistry 12 (1956) 1982.
The samples are dried for 15-20 h at 105°C and the BET
surface area determined according to DIN 66131 (volumetric
method).
The samples were dried for 15-20 h at 105°C and the
micropore volume determined by the t-plot method according
to DIN 66135-2.
The samples are dried for 15-20 h at 105°C and the
mesopore distribution determined by the BJH method
according to DIN 66134.
The macropore volume (pores of widths > 30 or > 50 nm) is
determined with an Autopore II 9220 mercury porosimeter
(Micromeritics) in accordance with the generally known
principles and operating instructions in the range up to
400 mm. The samples are first dried for 15-20 h at 105°C.
The method serves to determine the pore volume and the
pore distribution in porous solids by measuring the volume
of mercury pressed in under rising pressure using the
method devised by Ritter and Drake according to DIN 66133.
The pore maxima for mesopores and macropores can be read
off directly from the corresponding graphs (cumulated
intrusion volume (ml/g) and log. differential pore volume
dV/dlog D) for the pore volume distribution (ml/g) as a
function of the pore diameter (mm) .
Determination of the bead distribution and bead fractions
by screen analysis is performed as follows:
The bead size distribution of preformed, granular,
microgranular or microbeaded silicas is determined. To
this end a defined amount of silica is separated with a
stack of screens having a varying, standardised mesh
width.
The content of the individual bead fractions is determined
by weighing. The following equipment is used: mechanical
screening machine (Ro-tap); precision balance: accuracy ±
0.01 g (Mettler)
Standard screens U.S. Standard No. 120, height 25 mm, 0:
200 mm; mesh widths: 300 mm (50 mesh); 150 mm (100 mesh);
75 mm (200 mesh)
The screens and a receiver are assembled in the specified
sequence, in other words with apertures decreasing in size
from the top to the bottom. 100 g of the sample to be
examined is weighed out using an appropriate scoop.
Preselecting the material by pouring or transferring the
shaped silica out of the storage vessel should be avoided.
After transferring the weighed out silica onto the
uppermost screen a cover is placed on top and the stack
placed into the screening machine in such a way that a
clearance of approx. 1.5 mm remains to enable the screens
to rotate freely.
The screens are secured in the machine and then shaken for
5 min - with the vibrator or knocker operating. The
screens are then taken apart in turn and the amount of
silica contained within each is weighed to an accuracy of
0.1 g. A repeat determination is performed for each
sample. The mean of the amounts of silica found in the
individual screens and in the receiver is given in % in
each case.
The particle size distribution in the samples is
determined by laser diffraction analysis without
ultrasonic treatment using a Coulter LS 100 with dry
powder module (Beckman-Coulter) in accordance with the
generally known principles and operating instructions. A
continuous stream of original, untreated particles from
the sample to be measured is passed in an air jet through
a laser beam for 60 sec. The stream of particles is
penetrated by the laser and the various grain sizes
(particle sizes) are detected and evaluated statistically.
The minimum and maximum particle sizes that can be
measured are 0.4 |im and 900 |im respectively.
Determination of the particle size distribution after
ultrasonic treatment (degradation behaviour of the
samples) is performed by laser diffraction analysis using
a Coulter LS 100 with microvolume module (Beckman-Coulter)
in accordance with the generally known principles and
operating instructions after the sample has been
predispersed in ethanol and treated for 60 sec. in a
closed screw-cap jar in an ultrasonic bath (US bath RK100,
Bandelin). The minimum and maximum particle sizes that can
be measured are 0.4 mm and 900 Jim respectively.
In order to determine the average sulfur content in the
samples, samples are taken from the autoclave trays at
both ends of the tray and in the middle, and their sulfur
content determined by known methods by:
Schoniger digestion in an oxygen atmosphere (cf. F.
Ehrenberger, S. Gorbauch, "Methoden der organischen
Elementar- und Spurenanalyse", Verlag Chemie GmbH,
Weinheim/BergstraSe, 1973) and
subsequent ion-chromatographic analysis (ion
chromatograph 690 from Metrohm; PRP X-100 column from
Hamilton; mobile solvent: 2 mmol salicylate buffer,
pH 7) according to DIN ISO 10304-2.
The average sulfur content in the overall sample is then
obtained as the arithmetic mean of the 3 values for
individual samples determined in this way.
The water content in the samples is determined as follows:
10 g of the silanised silica are crushed for 15 seconds in
a coffee grinder and the water content is then determined
in accordance with the known principles that are familiar
to the person skilled in the art using a Karl Fischer
titrator (Metrohm, 720 KFS Titrino) and the Karl Fischer
titration chemicals no. 1.09241, no. 1.09243 and no.
1.06664 (disodium tartrate dihydrate) available from
Merck.
The carbon content in the samples is determined by known
standard methods using a CS-244 carbon/sulfur determinator
from LECO.
By reference to the procedure described in Kautschuk,
Gummi, Kunststoffe 51, (1998) 525 by Hunsche et al. the
residual alcohol (ethanol) on the filler is determined as
follows:
10 ml diethylene glycol monobutyl ether (DEGMBE) and
0.3 ml 0.5 mol/1 H2SO4 are added to 1 g of the filler
according to the invention in a glass ampoule that is
closed with a tight-fitting cap after being filled. The
mixture is thoroughly mixed in the glass ampoule for 20
min at 60°C in a water bath. 10 ml decane are then added
to the mixture, the temperature of which has been rapidly
adjusted to 25°C. Appropriate amounts are then removed
from the thoroughly mixed organic phase for HPLC analysis
(HPLC device with Jasco 851-AS autosampler, Jasco PU 980
pump, 7515A RI detector; TiO2 column, 250x4.5 mm, 5 |im,
YMC; mobile phase: DEGMBE with cyclohexane; temperature
25°C) on ethanol.
The shape factor and circle factor of the samples is
determined as follows:
REM analyses of pulverised powders of the fillers
according to the invention are performed on a Jeol JSM
6400 scanning electron microscope and analysed on-line
using the image analysis software Analysis 3.2 from SIS
(soft imaging software) in accordance with the
conventional principles and procedures known to the person
skilled in the art:
Circle factor (FCIRCLE)
The circle factor (FCIRCLE) indicates by how much the
particle shape differs from the ideal circular shape.
4p(Area)
FCIRCLE = P2
(1.0 for circular, Area = area of a particle, calculated from the number of
pixels that fall on a particle and the partial area of one
pixel
P = perimeter (i.e. the circumference of the more or less
complex particle)
Shape factor (FSHAPE)
D MIN
Shape factor FSHAPE = D MAX
The shape factor (FSHAPE) indicates by how much the
particle shape differs from the ideal circular shape by
considering 2 possible diameters of a particle (D min, D
max) .
(1.0 for circular and other exactly isometric aggregates,
D MIN = minimum diameter of a particle under consideration
D MAX = maximum diameter of the same particle under
consideration
Tables 6-10 show the analytical results.
Micrographs measuring 5.65 x 4 mm are taken of the samples
Ultrasil 7005 and Example no. 2 (Table 11) at a
magnification of 20:1 (Ultrasil 7005: 2 micrographs;
sample no. 2: 4 micrographs) using the scanning electron
microscope and the images obtained are selected
statistically on the basis of the criteria set out in
Table 12 and analysed statistically with regard to shape
factor and circle factor.
A micrograph measuring 178 mm x 126 mm is taken of the
sample Coupsil 8108 (powder) (Table 11) at a magnification
of 500:1 using the scanning electron microscope and the
image obtained is selected statistically on the basis of
the criteria set out in Table 12 and analysed
statistically with regard to shape factor and circle
factor.
The ID classes (Table 12) select and define the discrete
criteria for shape factor and circle factor from the
statistical analyses.
The particle size distributions by laser diffraction
without ultrasonic treatment are set out in Table 13.
Examples for the use of fillers according to the invention
in rubber compounds
Production of rubber compounds
The formulation used for the rubber compounds is shown in
Table 14 below. The unit phr denotes contents by weight,
relative to 100 parts of the crude rubber used. The
general method for producing rubber compounds and
vulcanisates thereof is described in the following book:
"Rubber Technology Handbook", W. Hofmann, Hanser Verlag
1994.

The polymer VSL 5025-1 is a solution-polymerised SBR
copolymer from Bayer AG with a styrene content of 25 wt.%
and a butadiene content of 75 wt.%. 73 % of the butadiene
is 1,2-linked, 10 % cis-1,4-linked and 17 % trans-1,4-
linked. The copolymer contains 37.5 phr of oil and
displays a Mooney viscosity (ML l+4/100°C) of 50 ±4.
The polymer Buna CB 24 is a cis-1,4-polybutadiene
(neodymium-type) from Bayer AG with a cis-1,4 content of
97 %, a trans-1,4 content of 2 %, a 1,2 content of 1 % and
a Mooney viscosity of 44 ±5.
Naftolen ZD from Chemetall is used as the aromatic oil.
Vulkanox 4020 is a 6PPD from Bayer AG and Protector G35P
is an anti-ozonant wax from HB-Fuller GmbH. Vulkacit D
(DPG) and Vulkacit CZ (CBS) are commercial products from
Bayer AG.
The coupling reagent Si 69 is a bis-(triethoxysilyl
propyl) tetrasulfane from Degussa AG. Ultrasil 7005 is a
beaded, readily dispersible precipitated silica from
Degussa AG with a BET surface area of 185 m2/g. Ultrasil
VN 3 is also a precipitated silica from Degussa AG with a
BET surface area of 175 m2/g. VP Coupsil 8108 is a known
silane-modified filler and is available from Degussa AG as
an experimental product. It is the silica Ultrasil VN 3,
presilanised with 8 parts by weight of Si 69 per 100 parts
by weight of Ultrasil VN 3.
The rubber compounds are produced in an internal mixer
according to the mixing instructions in Table 15.
The rubber test methods are summarised in Table 16.

Compound examples 1 to 4
In compound examples 1 to 4 the reference mixture mixed in
situ (formulation A) with 6.4 phr of the coupling reagent
Si 69 is compared with four compounds (formulation B) with
the silane-modified silicas according to the invention as
reproduced in Table 17.

Examples for the production of the fillers according to
the invention were described in Tables 1, 2, 3, 4 and 5.
The formulations used (A) and (B) are set out in Table 14
and the mixing instructions used are shown in Table 15.
The results of the rubber tests are summarised in Tables
18 to 21.
Table 18
As can be seen from the data in Tables 18 to 21, the
viscosities ML (1+4) and the vulcanisation characteristics
5 of the example compounds are at a similar level to those
of the in-situ reference compounds. The static and dynamic
rubber data is comparable within the limits of
conventional variations in rubber tests. The consistently
higher value for the reinforcing factor RF 300%/100% for
10 the example compounds in comparison to the in-situ
reference compounds indicates a higher silica-silane
bonding. This all clearly shows that the use of the silica
according to the invention leads to rubber properties that
are comparable with or tend to be better than those of the
in-situ reference. This cannot be achieved with silanised
fillers corresponding to the prior art.
Compound example: prior art
The compound example for the prior art shows that as
compared with the in-situ reference compound (formulation
C) the rubber properties deteriorate when the commercial
presilanised silica VP Coupsil 8108 (formulation D) is
used. Formulations (C) and (D) are based on the
formulations shown in Table 14. In a variation of the
mixing instructions used in formulations (A) and (B) and
set out in Table 14, in this example the second mixing
stage is mixed at an initial speed of 80 rpm and a
throughput temperature of 80°C. This is only a minor
deviation, however. The results are set out in Table 22.

The values from Table 22 show that the high level of the
in-situ reference compound is not achieved when the known,
presilanised silica VP Coupsil 8108 is used. Both the
higher Mooney viscosity and the higher Shore-A hardness
indicate an unsatisfactorily homogeneous silanisation,
leading to a higher filler network in compound (D). The
reinforcing factor RF 300%/100% for compound (D) also
drops significantly as compared with reference (C).
The advantage of using the silicas according to the
invention lies in the fact that in contrast to the known
in-situ silanisation used according to the prior art with
liquid silanes, such as e.g. Si 69, there is no need to
perform a chemical reaction, requiring an optimum process
control, during the mixing process. Furthermore, in the
known in-situ silanisation considerable amounts of alcohol
are disadvantageously liberated, which escape from the
compound and thus lead to problems in the exhaust air.
The compound examples clearly show that the use in rubber
of the presilanised silicas according to the invention
results in properties that are comparable to or better
than in-situ silanisation according to the prior art,
without causing the aforementioned disadvantages such as
arise in the known in-situ silanisation. By contrast,
although the cited problem of ethanol evolution during
mixing is avoided with the use of commercial presilanised
silicas, such as e.g. VP Coupsil 8108, the high technical
standard of the in-situ reference is not achieved.
WE CLAIM;
Silane -modified oxidic or siliceous filler, characterized in that
the bead fraction below 75 mm is less than 15 wt.%, determined
by screen analysis, and the median particle size is between 130
and 500 mm, determined by laser diffraction without ultrasonic
treatment.
Silane -modified oxidic or siliceous filler as claimed in claim 1,
wherein the statistically determined mean circle factor for the
particles is greater than 0.55.
Silane-modified oxidic or siliceous filler as claimed in claim 1,
wherein the statistically determined mean shape factor for the
particles is greater than 0.805.
Silane-modified oxidic or siliceous filler as claimed in claim 1,
wherein the BET surface area is between 0.5 m2/g and 500
m2/g-
Silane-modified oxidic or siliceous filler as claimed in claim 1,
wherein the content of carbon in pure or chemically bonded
form is between 0.1 and 25 wt%.
Silane-modified oxidic or siliceous filler as claimed in claim 1,
wherein the content of physically and chemically bonded
alcohol is between 0 and 25 wt.%.
Silane-modified oxidic or siliceous filler as claimed in claim 1,
wherein the residual content of the alcohol deriving from the
silane is less than 75 mol% of the initial amount of alcohol in
the silane used.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 1, wherein at least one
microbeaded or microgranular, oxidic or siliceous filler is
reacted with at least one silane in a gas compressed by means
of pressure and/or temperature.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein an organo silicon
compound or a mixture of organosilicon compounds having the
formula (I)
Z-A-Sx-A-Z (I)
is used as the silane, in which formula
x is a number from 1 to 14,
Z equals SiX1X2X3 and
X1X2X3 can each mutually independently denote
hydrogen (-H)
halogen or hydroxy (-OH),
an alkyl substituent,
an alkyl acid substitutent (CxH2x+1)C(=O)O-,
an alkenyl acid substituent or
a substituted alkyl or alkenyl acid substituent,
a linear or branched, "cyclic hydrocarbon chain with 1-8 carbon
atoms,
a cycloalkane radical with 5-12 carbon atoms,
a benzyl radical or
a halogen-or alkyl substituted phenyl radical,
alkoxy groups with linear or branched hydrocarbon
chains having (C1-24) atoms,
alkoxy groups with linear or branched polyether chains
having (C1-24) atoms,
a cycloalkoxy group having (C5-12) atoms,
a halogen- on alkyl-substituted phenoxy group or
a benzyloxy group,
A is a branched or unbranched, saturated or unsaturated
aliphatic, aromatic or mixed aliphatic/aromatic divalent
hydrocarbon chain comprising C1-C30.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 9, wherein
[(EtO)3Si(CH2)3]2S, [EtO)3Si(CH2)3]2S2,
[(EtO)3Si(CH2)3]2S3, [EtO)3Si(CH2)3]2S4,
[(EtO)3Si(CH2)3]2S5, [EtO)3Si(CH2)3]2S6,
[(EtO)3Si(CH2)3]2S7, [EtO)3Si(CH2)3]2S8,
[(EtO)3Si(CH2)3]2S9, [EtO)3Si(CH2)3]2Sio,
[(EtO)3Si(CH2)3]2Sn, [EtO)3Si(CH2)3]2Si2,
[(EtO)3Si(CH2)3]2Si3, [EtO)3Si(CH2)3]2Si4,
[(CyHyx+1O) (R )2 Si (CH2)3] Sx[(CH2)3Si ( R ) 3],
[(CyH2y+1O)2 (R ) Si (CH2)3] Sx[(CH2)3Si ( R ) 3],
[(CyH2y+1O)3 Si (CH2)3] Sx[(CH2)3Si ( R ) 3],
[(CyH2y+1O) (R )2 Si (CH2)3] Sx[(CH2)3Si. (CyH2y+1O) (R )2],
[(CyH2y+1O)2 (R ) Si (CH2)s] Sx[(CH2)3Si (CyH2y+1O) (R )2],
[(CyH2y+1O)3 Si (CH2)3] Sx[(CH2)3Si (CyH2y+1O) (R )2],
[(CyH2y+1O) (R )2 Si (CH2)3] Sx[(CH2)3Si (CyH2y+1O)2 (R )],
[(CyH2y+1O)2 (R ) Si (CH2)3] Sx[(CH2)3Si (CyH2y+1O)2 (R )],
[(CyH2y+1O)3 Si (CH2)3] Sx[(CH2)3Si (CyH2y+iO)2 (R )],
[(CyH2y+1O) ( R )2 Si (CH2)3] Sx[(CH2)3Si (CyH2y+1O)3 ],
[(CyH2y+1O)2 (R ) Si (CH2)3] Sx[(CH2)3Si (CyH2y+1O)3],
[(CyH2y+1O)3 Si (CH2)3] Sx[(CH2)3Si (CyH2y+1O)3],
where x=l-14, y=10-24 and R=(MeO) or/and (EtO), or mixtures
of the individual silanes, are used as the silane having formula
(I).
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein an organosilicon
compound or mixtures of organosilicon compounds having the
general formula (II)
X1x2X3Si-A-S-SiR1R2R3 (II)
are used as the silane, in which formula
X1,X2,X3 and A mutually independently have the same meaning
as in formula (I),
R1,R2,R3 are each mutually independent and denote (C1-C16)
alkyl, (C1-C16)alkoxy, (C1-C16) haloalkyl, aryl, (C7-C16)aralkyl,
-H , halogen or X1X2X3Si-A-S-.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein that an
organosilicon compound or a mixture of organosilicon
compounds having the general formula (III)
X1X2X3Si-Alk (III)
is used as the silane , in which formula
X1,X2,X3 each mutually independently have the same
meaning as in formula (I) and
Alk is a straight-chain, branched or cyclic (C1-C24) alkyl, (C1-
C24) alkoxy, halogen, hydroxy, nitrile, thiol, (C1-C4) haloalkyl,
-NO2, (C1-C8) thioalkyl, -NH2, -NHR1, -NR1R2, alkenyl, allyl,
vinyl, aryl or a (C7-C16) aralkyl substituent.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 12, wherein (MeO)3-Si-(CH2)3-
H, (EtO)3-Si-(CH2)3-H, (MeO)3-Si-C(CH3)3, (EtO)3-Si-
C(CH3)3,(MeO)3-Si-(CH2)8-H, (EtO)3-vSi-(CH2)8-H, (MeO)3-Si-
(CH2)16-H, (EtO)3-Si-(CH2)16-H, Me3Si-OMe, Me3Si-OEt,Me3Si-Cl,
EtsSi-Cl, (MeO)3Si-CH=CH2, (EtO)3Si-CH=CH2, (Me3Si)2N-C(O)-
H, (Me3Si)2N-H or mixtures of the silanes are used as the silane
having formula (III).
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein an organosilicon
compound or a mixture of organosilicon compound having the
general formula (IV) or (V).
[[ROC(=O))p-(G)j]k-Y-S]r-G-(SiX1X2X3)s (IV)
[(X1X2X3Si]q-G]a— [Y-[S-G-SiX1X2X3]b]c (V) is
used as the silane,
in which formulae Y represents a polyvalent species
(Q)ZD(=E), whereby the following is true:
p is 0 to 5, r is 1 to 3, z is 0 to 2; q is 0 to 6, a is 0 to 7, b is 1 to
3, j is 0 to 1, but if p=l it can also commonly be 0, c is 1 to 6, t
is 0 to 5, s is 1 to 3, k is 1 to 2, under the proviso that
(1) if (D) is a carbon, sulfur or sulfonyl., a+b=2 and k=l,
(2) if (D) is a phosphorus atom, a +b=3 provided
that c= 1 and b= 1, whereby a=c+1,
(3) if (D) is a phosphorus atom, k=2,
Y represents a polyvalent specifies (QZD(=E),
in each of these groups the atom (D) is doubly bonded to the
hereroatom (E), which in turn is bonded to the sulfur atom (S),
which is coupled to the silicon atom (Si) by means of a group
(G),
R1 mutually independently denotes H, a straight, cyclic or
branched alkyl chain, optionally alkyl chains containing
unsaturated components such as double bonds (alkenes),
triples bonds (alkynes) or alkyl aromatics (aralkyl) or aromatics
and displaying the same meanings as in formula (II),
G independently of the other substituents denotes hydrogen, a
straight, cyclic or branched alkyl chain with (C1-C18), whereby
the alkyl chains can optionally contain an unsaturated
component,
If p=0 in the formula, G is preferably hydrogen (H), G does not
correspond to the structure of an a, b -unsaturated fragment
that is bonded to the Y fragment in such a way that an a, b-
unsaturated thiocarbonyl fragment is formed,
X1, X2 and X3 each mutually independently have the meaning
as in formula (I).
Process or the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein an organosilicon
compound or a mixture of organosilicon compounds having the
general formula (VI)
X1X2X3Si-A-Sub (VI)
is used as the silane, where by X1X2X3 and A, each mutually
independently, have the meaning according to formula (I) and
Sub is -NH2,-SH, -NH (A- SiX1X2X3), -N(A-SiX1X2X3)2, O-C(O)-
CMe=CH2 or -SCN.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 15, wherein ([MeO)3Si-(CH2)3-
]2NH, [EtO)3Si-(CH2)3-]2NH, [(C3H7O)3Si-(CH2)3-]2NH, (MeO)3Si-
(CH2)3-NH2, (EtO)3Si-(CH2)3-NH2, (C3H7O)3Si-(CH2)3-NH2,
(MeO)3Si-(CH2)3-NH-(CH2)2-NH2, (EtO)3Si-(CH2)3-NH-(CH2)2-NH2,
(C3H7O)3Si-(CH2)3-NH-(CH2)2-NH2,(MeO)3Si-(CH2)3-SH, (EtO)3Si-
(CH2)3-SH, (C3H7O)3Si-(CH2)3-SH, (MeO)3Si-(CH2)3-O-C(O)-
CMe=CH2,(EtO)3Si-(CH2)3-O-C(O)-CMe=CH2,(C3H7O)3Si-(CH2)3-
O-C(O)-CMe=CH2,SCN, (EtO)3Si-(CH2)3-SCN, (C3H7O)3Si-(CH2)3-
SCN,
[(CYH2Y+1O)EtO)2Si (CH2)3]-NH2, [(CYH2Y+1O)2(EtO)Si(CH2)3]NH2,
[(CyH2y+1O) (EtO)2Si (CH2)3]-SH, [(CYH2Y+1O)2 (EtO)Si (CH2)3]-SH,
[(CyH2y+1O) (EtO)2Si (CH2)3]-O-C(O)-CMe=CH2, [(CyH2y+1O)2
(EtO)Si (CH2)3]-O-C(O)-CMe=CH2 where y= 10-24, or mixtures of
the cited silanes, are used as the silane having formula (VI).
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein mixtures of the
silanes having formulae I-VI are used as the silane.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein oligomeric or
cooligomeric silanes having formulae 1-VI or mixtures thereof or
mixtures of silanes having formulae I-VI and oligomers or
cooligomers thereof are used as the silane.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein that a natural
and/or synthetic filler is used as the microbeaded or
microgranular, oxidic or siliceous filler.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein microbeaded or
microgranular kaolein, kieselguhr, mica, diatomaceous earth,
clay, talc, wollastonite, silicates inter alia in the form of glass
beads, ground glass chips (glass powder), glass fibres or glass
clothes, zeolites, aluminium oxide, aluminium hydroxide,
trihydrate, aluminium silicates, silicates, precipitates silicas
with BET surface areas (measured with gaseous nitrogen) of 1
to 1000 m2/g, zinc oxide, boron oxide, magnesium oxide or
generally transition metal oxides are used as the microbeaded
or microgranular, oxidic or siliceous filler.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein 10-250 parts by
weight of microbeaded or microgranular, oxidic or siliceous
filler are reacted with 0.1-50 parts by weight of silane.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein carbon dioxide,
helium, nitrogen, dinitrogen monoxide, sulfur hexafluoride,
gaseous alkanes with 1 to 5 C atoms, gaseous alkenes with 2 to
4C atoms, gaseous alkynes, gaseous dienes, gaseous
fluorocarbons, chlorinated hydrocarbons and/or
chlorofluorocarbons or substituents thereof or ammonia, and
mixtures of these substance, are used as the compressed gas.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein the silanes used
are undissolved, partially or wholly dissolved in the compressed
gas.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein the pressure is
between 1 and 500 bar.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein the reaction takes
place at a temperature of between 0 to 300°C.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein during the
reaction the pressure is kept constant at various pressure
levels for periods of 5-720 min and during this time the filler is
immerised or stirred in the compressed gas or the compressed
gas is passed through it.
Process for the production of the silane modified oxidic or
siliceous filler as claimed in claim 8, wherein the microbeaded
or microgranular, oxidic or siliceous filler and the silane are
first mixed together or brought into contact and then mixed or
brought into contact with the gas in compressed form.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein the microbeaded
or microgranular, oxidic or siliceous filler is first mixed together
or brought into contact with the gas in compressed form and
then mixed or brought into contact with the silane.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein the silane is first
mixed together or brought into contact with the gas in
compressed form an then mixed or brought into contact with
the corresponding microbeaded or microgranular, oxidic or
siliceous filler.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein additional
additives are added to the microbeaded or microgranular,
oxidic or siliceous filler and/or silane before the reaction in the
compressed gas or mixture of gases.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim. 8, wherein the silane-
modified oxidic or siliceous filler is brought into contact with
additional additives during the reaction in the compressed gas.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in claim 8, wherein additional
additives are incorporated into the incoming or outgoing stream
of compressed gas passing through the silane-modified oxidic
or siliceous filler during the reaction of the microbeaded or
microgranular, oxidic or siliceous filler in the compressed gas.
Process for the production of the silane-modified oxidic or
siliceous filler as claimed in one of claims 30-32, wherein
ammonia, sulfur dioxide, water, shot-chain or long-chain
alcohols, short-chain or long-chain polyethers or short-chain or
long-chain amines, emulsifiers or short-chain or long-chain
silicone oils are used as additives.
Silane-modified oxidic or siliceous filler with a bead
fraction below 75 mm of less than 15 wt.% and a median
particle size distribution between 150 and 500 mm, which
is produced by the reaction of at least one microbeaded or
microgranular, oxidic or siliceous filler in a compressed
gas with at least one silane.
The silane-modified oxidic or siliceous fillers are used
in rubber compounds.

Documents:

226-KOL-2003-CORRESPONDENCE.pdf

226-KOL-2003-FORM 27.pdf

226-KOL-2003-FORM-27.pdf

226-kol-2003-granted-abstract.pdf

226-kol-2003-granted-claims.pdf

226-kol-2003-granted-correspondence.pdf

226-kol-2003-granted-description (complete).pdf

226-kol-2003-granted-examination report.pdf

226-kol-2003-granted-form 1.pdf

226-kol-2003-granted-form 18.pdf

226-kol-2003-granted-form 2.pdf

226-kol-2003-granted-form 3.pdf

226-kol-2003-granted-form 5.pdf

226-kol-2003-granted-gpa.pdf

226-kol-2003-granted-priority document.pdf

226-kol-2003-granted-reply to examination report.pdf

226-kol-2003-granted-specification.pdf

226-kol-2003-granted-translated copy of priority document.pdf

226-KOL-2003-OTHERS-(30-11-2011).pdf

226-KOL-2003-PA.pdf


Patent Number 223851
Indian Patent Application Number 226/KOL/2003
PG Journal Number 39/2008
Publication Date 26-Sep-2008
Grant Date 23-Sep-2008
Date of Filing 16-Apr-2003
Name of Patentee DEGUSSA AG
Applicant Address BENNIGSENPLATZ 1 DE-40474 DÜSSELDORF
Inventors:
# Inventor's Name Inventor's Address
1 KORTH, DR. KARSTEN SOLVAYSTRASSE 10A, DE-79639 WYHLEN
2 EICHENAUER, KURT JOSEF-DIETER-WEG 11, DE-63628 BAD SODEN-SALMÜNSTER
3 PIETER, DR. REIMUND JASMINWEG 4A, DE-64625 BENSHEIM
4 KLOCKMANN, DR. OLIVER GERTRUDENHOFWEG 4, DE-50858 KÖLN
5 HEIDLAS, DR. JÜRGEN BERGLEITE 11, DE-83308 TROSTBERG
6 OBER, MARTIN RUPERTSDORF 5, DE-83352 ALTENMARKT
7 ZOBEL, RUDOLF AN DEN WEIDEN, DE-97348 WILLANZHEIM
PCT International Classification Number C08L 21/00
PCT International Application Number N/A
PCT International Filing date
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 102 18 350.3 2002-04-25 Germany