Title of Invention	"A PROCESS FOR PREPRATION OF MODIFIED POLYPROPYLENE MOULDING COMPOUND HAVING HIGH IMPACT STRENGTH"
Abstract	A process for preparation of polypropylene moulding compound which comprises complexing calcium chloride with a high molecular weight polymer dissolved in a non-aqueous solvent, digesting for 10 to 12 hrs, reacting the resultant with solution of carbonate of sodium or potassium in a different solvent, allowing the resultant to stand for more than 10 hrs to obtain a precipitate, filtering the said precipitate, drying the same to get a powder form at a temperature ranging from 40 to 50°C and mixing it with polypropylene powder in the range of 1 to 20 wt % to form a homogenous solid, moulding the resultant to obtain high crystallinity and high impact polypropylene moulding compound

Title of Invention

"A PROCESS FOR PREPRATION OF MODIFIED POLYPROPYLENE MOULDING COMPOUND HAVING HIGH IMPACT STRENGTH"

Abstract

A process for preparation of polypropylene moulding compound which comprises complexing calcium chloride with a high molecular weight polymer dissolved in a non-aqueous solvent, digesting for 10 to 12 hrs, reacting the resultant with solution of carbonate of sodium or potassium in a different solvent, allowing the resultant to stand for more than 10 hrs to obtain a precipitate, filtering the said precipitate, drying the same to get a powder form at a temperature ranging from 40 to 50°C and mixing it with polypropylene powder in the range of 1 to 20 wt % to form a homogenous solid, moulding the resultant to obtain high crystallinity and high impact polypropylene moulding compound

Full Text	This invention relates to A PROCESS FOR PREPARATION OF MODIFIED POLYPROPYLENE MOULDING COMPOUND HAVING HIGH IMPACT STRENGTH. More particularly it relates to the prepaaralion of polypropylene moulding compound with high cryslallinity and high impact strength by using additives prepared in situ. There has been considerable demand for enhancement of properties in commodity polymers such as polypropylene through modification of structure and cryslallinity. High cryslallinity is essential for increase in mechanical strength . High cryslallinity is usually induced by changing the processing parameters or by using particular nucleating agenls which enhance the crystallization process. However, the increase of mechanical strength by such methods gives rise to very low impact strength. On the other hand when one modifies the polymer through introducing co-monomer or by blending with another elastomeric polymer for obtaining higher impact strength, the cryslallinity decreases considerably. The main drawback of the presently available lechniques is that when one modifies the polymer to obtain high cryslallinity the impact strength decreases and they do not yield both high cryslallinity as well as high impact strength in polypropylene moulding compound. Thc preparation of polypropylene moulding compound having high cryslallinity and high impact strength by using additives prepared in situ has not been reported in the prior art. The main object of the present invention is to provide a process for preparation polypropylene moulding compound having high cryslallinity and high impact strength by using additives prepared in situ. Accordingly, the present invention provides a process for preparation of polypropylene moulding compound which comprises complexing calcium chloride with a high molecular weight polymer dissolved in a non-aqueous solvent, digesting for 10 to 12 hrs, reacting the resultant with solution of carbonate of sodium or potassium in a different solvent, allowing the resultant to stand for more than 10 hrs to obtain a precipitate, filtering the said precipitate, drying the same to get a powder form at a temperature ranging from 40 to 50°C and mixing it with polypropylene powder in the range of 1 to 20 wt % to form a homogenous solid, moulding the resultant to obtain high crystallinity and high impact polypropylene moulding compound In an embodiment of the present invention, the non aqueious solvent used is selected from alcohols preferably methanol, ethanol, butanol. In another embodiment of the present invention, the solvent used for preparing the solution of carbonates of sodium and potassium are selected from high solubility parameter preferably water, dimethyl sulfoxide, dimethyl formamide. In an embidiment of the present invention, the polymer used for complexing contains ether or hydroxyl group having molecular weight > 105. In the preferred range of compositions and moulding conditions, the crystallinity of polypropylene increases to almost 75% and simultaneously the impact strength increases 1.5 to 1.75 times that for polypropylene without the additive. Thus high crystallinity is induced in the polypropylene mouldings without the loss of impact strength using the additive prepared by the present invention. The invention is illustrated by the following examples which however, should not be construed to limit the scope of the invention. EXAMPLE - 1 The calcium chloride (28 gms) was dissolved in methyl alcohol (100 ml) with continuous stirring until clear solution was obtained to which were added high molecular weight (M.W. > 105) polyethylene oxide (2 gms) with continuous stirring. The solution was allowed to digest at 30"C Tor 10 hrs. An aqueous solution of potassium carbonate (18% by wt) was slowly trickled into the digested solution of polyethylene oxide and calcium chloride. This was allowed to stand at room temperature ("or 10 hrs. A white precipitate (I) was obtained which was liltcred, washed and dried. A desired amount (0.126 gms) of (I) were added to polypropylene moulding powder (particle si/e better than 40 mesh) (2.0 gms) and dry mixed Ibr 20 mins. This mixture was compression moulded at 1.5 tons clamp pressure and 170oC mould temperature with 30min cycle time to obtain polypropylene moulded sample having high crystallinity and high impact strength. The properties of the resulting product are given in Table - 1. EXAMPLE - 2 The calcium chloride (27.7 gms) was dissolved in methyl alcohol (120 ml) with continuous stirring to which were added high molecular weight polyethylene oxide (M.W. > 104) (0.8 gms) and allowed to digest at 30oC Ibr 10 hrs. An aqueous solution of potassium carbonate (18% by wt,20{) ml) was trickled into the digested solution of polyethylene oxide and calcium chloride with no stirring and allowed to stand at room temperature for 10 hrs. The white pricipitate obtained (I) was filtered, washed and dried. The polpropylene moulding powder (particle size better than 40 mesh) (2.5 gms) was dry mixed with the precipitate (I) (0.25 gms) for 30 min. This mixture was then compression moulded at 1.5 tons clamp pressure, 170oC mould temperature and 30 min cycle lime to obtain polypropylene moulded sample. The properties of this product are given in Table - 1. EXAMPLE - 3 The calcium chloride (27.7 gms) was dissolved in water to which were added a souition of potassium carbonate(18% by wt, 200 ml) to from instantly the precipitate of calcium carbonate. This was filtered and dried. The polypropylene moulding powder ( particle size better than 40 mesh) (2.5 gms) were dry mixed with calcium carbonate (0.2 gms) for 30 min. This mixture was compression moulded at 1.5 tons clamp pressure, 170oC mould temperature and 30 min cycle time to obtain polypropylene moulded sample. The properties of the resulting product are given in Table - 1. TABLE - 1 ; Properties of polypropylene with and without present additive (Table Removed) It can be inferred from (he above data that the crystallinity and impact strength arc lower in pure polypropylene as well as polypropylene containing calcium carbonate prepared without pre-complex formation (Example 3) than that in the polypropylene conlaining the additive made by the present invention. In the suilal)ie range of composition, very high crystallinity can be induced in the polypropylene moulding compound with simultaneous increasc in the impact strength. The main advantages of the present invention arc : 1. The process can be used to produce the additive using commonly available materials. 2 High crystallinity can be induced in polypropylene which otherwise is not possible lor this polymer unless synlhesised by special routes using expensive catalysts. 3, High crystallinity is induce without the loss of impact strength. 4. Impact strength is also improved considerably with simple addition and compounding process without any elaborate chemical reactions as required for co-polymerization using expensive techniques. We Claim: 1. A process for preparation of polypropylene moulding compound which comprises complexing calcium chloride with a high molecular weight polymer dissolved in a non-aqueous solvent, digesting for 10 to 12 hrs, reacting the resultant with solution of carbonate of sodium or potassium in a different solvent, allowing the resultant to stand for more than 10 hrs to obtain a precipitate, filtering the said precipitate, drying the same to get a powder form at a temperature ranging from 40 to 50°C and mixing it with polypropylene powder in the range of 1 to 20 wt % to form a homogenous solid, moulding the resultant to obtain high crystaliinity and high impact polypropylene moulding compound. 2. A process as claimed in claim 1 wherein the non-aqueous solvent is selected from alcohols such as methanol, ethanol, butanol. 3. A process as claimed in claims 1 an d2 wherein solvent used fro preparing the solution of the carbonates of sodium or potassium is selected from high solubility parameter (i.e.>12) preferably water, dimethyl sulfoxied, dimethyl formamide, 4. A process as claimed in claims 1 to 3 wherein the polymer used for complexing contains ether or hydroxyl group having molecular weight in the range of 103 to 106 preferably 105 5. A process as claimed in claims 1 to 4 wherein the concentration of the precipitate used for mixing with polypropylene is in the range of 2 to 40% by wt, preferably 2 to 15% by wt. of polypropylene. 6. A process as claimed in claims 1 to 5 wherein the resultant precipitate is in powder form with particle size in the range of 2 to 12 microns, preferably 2 to 4 microns. 7. A process for the preparation of polypropylene moulding compound having high crystallinity and impact strength substantially as herein described with reference to examples.

Full Text

This invention relates to A PROCESS FOR PREPARATION OF MODIFIED POLYPROPYLENE MOULDING COMPOUND HAVING HIGH IMPACT STRENGTH. More particularly it relates to the prepaaralion of polypropylene moulding compound with high cryslallinity and high impact strength by using additives prepared in situ.
There has been considerable demand for enhancement of properties in commodity polymers such as polypropylene through modification of structure and cryslallinity. High cryslallinity is essential for increase in mechanical strength . High cryslallinity is usually induced by changing the processing parameters or by using particular nucleating agenls which enhance the crystallization process. However, the increase of mechanical strength by such methods gives rise to very low impact strength. On the other hand when one modifies the polymer through introducing co-monomer or by blending with another elastomeric polymer for obtaining higher impact strength, the cryslallinity decreases considerably. The main drawback of the presently available lechniques is that when one modifies the polymer to obtain high cryslallinity the impact strength decreases and they do not yield both high cryslallinity as well as high impact strength in polypropylene moulding compound.
Thc preparation of polypropylene moulding compound having high cryslallinity and
high impact strength by using additives prepared in situ has not been reported in the
prior art.
The main object of the present invention is to provide a process for preparation
polypropylene moulding compound having high
cryslallinity and high impact strength by using additives prepared in situ.
Accordingly, the present invention provides a process for preparation of polypropylene moulding compound which comprises complexing calcium chloride with a high molecular weight polymer dissolved in a non-aqueous solvent, digesting for 10 to 12 hrs, reacting the resultant with solution of carbonate of sodium or potassium in a different solvent, allowing the resultant to stand for more than 10 hrs to obtain a precipitate, filtering the said precipitate, drying the same to get a powder form at a temperature ranging from 40 to 50°C and mixing it with polypropylene powder in the range of 1 to 20 wt % to form a homogenous solid, moulding the resultant to obtain high crystallinity and high impact polypropylene moulding compound
In an embodiment of the present invention, the non aqueious solvent used is selected from alcohols preferably methanol, ethanol, butanol.
In another embodiment of the present invention, the solvent used for preparing the solution of carbonates of sodium and potassium are selected from high solubility parameter preferably water, dimethyl sulfoxide, dimethyl formamide.
In an embidiment of the present invention, the polymer used for complexing contains ether or hydroxyl group having molecular weight > 105.
In the preferred range of compositions and moulding conditions, the crystallinity of polypropylene increases to almost 75% and simultaneously the impact strength increases 1.5 to 1.75 times that for polypropylene without the additive. Thus high crystallinity is induced in the polypropylene mouldings without the loss of impact strength using the additive prepared by the present invention.
The invention is illustrated by the following examples which however, should not be construed to limit the scope of the invention.
EXAMPLE - 1
The calcium chloride (28 gms) was dissolved in methyl alcohol (100 ml) with continuous stirring until clear solution was obtained to which were added high molecular weight (M.W. > 105) polyethylene oxide (2 gms) with continuous stirring. The solution was allowed to digest at 30"C Tor 10 hrs. An aqueous solution of potassium carbonate (18% by wt) was slowly trickled into the digested solution of polyethylene oxide and calcium chloride. This was allowed to stand at room temperature ("or 10 hrs. A white precipitate (I) was obtained which was liltcred, washed and dried. A desired amount (0.126 gms) of (I) were added to polypropylene moulding powder (particle si/e better than 40 mesh) (2.0 gms) and dry mixed Ibr 20 mins. This mixture was compression moulded at 1.5 tons clamp pressure and 170oC mould temperature with 30min cycle time to obtain polypropylene moulded sample having high crystallinity and high impact strength. The properties of the resulting product are given in Table - 1.
EXAMPLE - 2
The calcium chloride (27.7 gms) was dissolved in methyl alcohol (120 ml) with continuous stirring to which were added high molecular weight polyethylene oxide (M.W. > 104) (0.8 gms) and allowed to digest at 30oC Ibr 10 hrs. An aqueous solution of potassium carbonate (18% by wt,20{) ml) was trickled into the digested solution of polyethylene oxide and calcium chloride with no stirring and allowed to stand at room temperature for 10 hrs. The white pricipitate obtained (I) was filtered, washed and dried. The polpropylene moulding powder (particle size better than 40 mesh) (2.5 gms) was dry mixed with the precipitate (I) (0.25 gms) for 30 min. This mixture was then compression moulded at 1.5 tons clamp pressure, 170oC mould temperature and 30 min
cycle lime to obtain polypropylene moulded sample. The properties of this product are given in Table - 1.
EXAMPLE - 3
The calcium chloride (27.7 gms) was dissolved in water to which were added a souition
of potassium carbonate(18% by wt, 200 ml) to from instantly the precipitate of calcium
carbonate. This was filtered and dried. The polypropylene moulding powder ( particle
size better than 40 mesh) (2.5 gms) were dry mixed with calcium
carbonate (0.2 gms) for 30 min. This mixture was compression moulded at 1.5 tons
clamp pressure, 170oC mould temperature and
30 min cycle time to obtain polypropylene moulded sample. The properties of the
resulting product are given in Table - 1.
TABLE - 1 ; Properties of polypropylene with and without present additive

(Table Removed)
It can be inferred from (he above data that the crystallinity and impact strength arc lower in pure polypropylene as well as polypropylene containing calcium carbonate prepared without pre-complex formation (Example 3) than that in the polypropylene
conlaining the additive made by the present invention. In the suilal)ie range of composition, very high crystallinity can be induced in the polypropylene moulding compound with simultaneous increasc in the impact strength.
The main advantages of the present invention arc :
1. The process can be used to produce the additive using commonly available materials.
2 High crystallinity can be induced in polypropylene which otherwise is not
possible lor this polymer unless synlhesised by special routes using expensive catalysts.
3, High crystallinity is induce without the loss of impact strength.
4. Impact strength is also improved considerably with simple addition and
compounding process without any elaborate chemical reactions as required for
co-polymerization using expensive techniques.

We Claim:
1. A process for preparation of polypropylene moulding compound which comprises complexing calcium chloride with a high molecular weight polymer dissolved in a non-aqueous solvent, digesting for 10 to 12 hrs, reacting the resultant with solution of carbonate of sodium or potassium in a different solvent, allowing the resultant to stand for more than 10 hrs to obtain a precipitate, filtering the said precipitate, drying the same to get a powder form at a temperature ranging from 40 to 50°C and mixing it with polypropylene powder in the range of 1 to 20 wt % to form a homogenous solid, moulding the resultant to obtain high crystaliinity and high impact polypropylene moulding compound.
2. A process as claimed in claim 1 wherein the non-aqueous solvent is selected from alcohols such as methanol, ethanol, butanol.
3. A process as claimed in claims 1 an d2 wherein solvent used fro preparing the solution of the carbonates of sodium or potassium is selected from high solubility parameter (i.e.>12) preferably water, dimethyl sulfoxied, dimethyl formamide,
4. A process as claimed in claims 1 to 3 wherein the polymer used for complexing contains ether or hydroxyl group having molecular weight in the range of 103 to 106 preferably 105
5. A process as claimed in claims 1 to 4 wherein the concentration of the precipitate used for mixing with polypropylene is in the range of 2 to 40% by wt, preferably 2 to 15% by wt. of polypropylene.
6. A process as claimed in claims 1 to 5 wherein the resultant precipitate is in powder form with particle size in the range of 2 to 12 microns, preferably 2 to 4 microns.
7. A process for the preparation of polypropylene moulding compound having high crystallinity and impact strength substantially as herein described with reference to examples.

Documents:

2626-del-1996-abstract.pdf

2626-del-1996-claims.pdf

2626-del-1996-complete specification (granted).pdf

2626-del-1996-correspondence-others.pdf

2626-del-1996-correspondence-po.pdf

2626-del-1996-description (complete).pdf

2626-del-1996-form-1.pdf

2626-del-1996-form-2.pdf

2626-del-1996-form-3.pdf

2626-del-1996-form-4.pdf

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Patent Number

195696

Indian Patent Application Number

2626/DEL/1996

PG Journal Number

31/2009

Publication Date

31-Jul-2009

Grant Date

07-Jul-2006

Date of Filing

29-Nov-1996

Name of Patentee

COUNCIL OF SCIENTIFIC AND INDUSTRIAL RESEARCH

Applicant Address

RAFI MARG NEW DELHI-110001 INDIA.

Inventors:

#	Inventor's Name	Inventor's Address
1	SUBRAMANIAM RADHAKRISHNAN	NATIONAL CHEMICAL LABORATORY PUNE-411 008 MAHARASHTRA INDIA.
2	ANAND AVINASH KHARE	NATIONAL CHEMICAL LABORATORY PUNE-411 008 MAHARASHTRA INDIA.
3	COMANDUR SAUJANYA	NATIONAL CHEMICAL LABORATORY PUNE-411 008 MAHARASHTRA INDIA.

PCT International Classification Number

C08L 23/00

PCT International Application Number

N/A

PCT International Filing date

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1			NA