US4156062A
Expired / Lapsed
US
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Process for toughening ethylene-vinyl acetate copolymers and resins obtained thereby
Assignee: Millennium Petrochemicals Inc
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Filing: 1977-05-09
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Granted: 1979-05-22
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Expires: 1997-05-09
Abstract
Abstract A process for toughening ethylene-vinyl acetate copolymers is disclosed which comprises reacting a rubbery ethylene-vinyl acetate copolymer with oxygen at elevated temperature in the presence of a catalytically effective amount of at least one catalyst selected from the group consisting of an alkali metal, ammonium or zinc salt of a weak aliphatic carboxylic acid, an alkali metal, ammonium or zinc salt of a weak aromatic carboxylic acid, an aliphatic tertiary amine, and an aromatic tertiary amine, for a period sufficient to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable increase in melt viscosity as indicated by a corresponding decrease in melt flow rate compared with that of the starting copolymer.
Inventors
- 👤 Ervin G. Pritchett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 02:46
CPC Classifications
C; C08; C08J; C08J5/00; C08J5/18; C08F; C08F8/00; C08F8/06; C08J2323/00; C08J2323/02; C08J2323/04; C08J2323/06
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
193 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery ethylene-vinyl acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate, having a melt index of from 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provide that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen at elevated temperature in the presence of a catalytically effective amount of at least one catalyst selected from the group consisting of an alkali metal, ammonium or zinc salt of an aliphatic carboxylic acid having a pH value in the range of from about 3 to about 10, an alkali metal, ammonium or zinc salt of an aromatic carboxylic salt having a pK value in the range of from about 3 to about 10, an aliphatic tertiary amine, and an aromatic tertiary amine, for a period sufficient to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable decrease in melt flow rate compared with the melt flow rate of the starting copolymer.
Claim 2
Dependent Claim
193 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery ethylene-vinyl acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate, having a melt index of from 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provide that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen at elevated temperature in the presence of a catalytically effective amount of at least one catalyst selected from the group consisting of an alkali metal, ammonium or zinc salt of an aliphatic carboxylic acid having a pH value in the range of from about 3 to about 10, an alkali metal, ammonium or zinc salt of an aromatic carboxylic salt having a pK value in the range of from about 3 to about 10, an aliphatic tertiary amine, and an aromatic tertiary amine, for a period sufficient to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable decrease in melt flow rate compared with the melt flow rate of the starting copolymer.
Claim 3
Dependent Claim
23 words
The process of claim 1 wherein the starting ethylene-vinyl acetate copolymer contains from about 35 to about 70 weight percent combined vinyl acetate.
Claim 4
Dependent Claim
12 words
The process of claim 1 wherein the oxygen is supplied as air.
Claim 5
Dependent Claim
32 words
The process of claim 1 wherein the catalyst is the salt of an aliphatic or aromatic carboxylic acid having a pK value in the range of from about 2 to about 6.
Claim 6
Dependent Claim
11 words
The process of claim 1 wherein the catalyst is sodium acetate.
Claim 7
Dependent Claim
28 words
The process of claim 1 wherein from about 0.001 to about 5 parts by weight of catalyst per hundred parts by weight of ethylene-vinyl acetate copolymer is employed.
Claim 8
Dependent Claim
28 words
The process of claim 1 wherein from about 0.01 to about 1 part by weight of catalyst per hundred parts by weight of ethylene-vinyl acetate copolymer is employed.
Claim 9
Dependent Claim
22 words
The process of claim 1 wherein the reaction temperature is in the range of from about 140° C. to about 225° C.
Claim 10
Dependent Claim
17 words
The process of claim 8 wherein the reaction time is from about 0.001 to about 1 hour.
Claim 11
Dependent Claim
17 words
The process of claim 9 wherein the reaction time is from about 0.01 to about 0.5 hours.
Claim 12
Dependent Claim
19 words
The process of claim 1 wherein the reaction is carried out at from about 0.01 to about 10 atmospheres.
Claim 13
Dependent Claim
186 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery ethylene-vinyl acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate having a melt index of from 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provided that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen supplied as air at a temperature of from about 140° C., to about 225° C. at a pressure of from about 0.01 to about 10 atmospheres in the presence of from about 0.001 to about 5 parts by weight of an alkali metal, ammonium or zinc salt of a weak aliphatic carboxylic acid or aromatic carboxylic salt having a pK value in the range of from about 2 to about 6 as catalyst for from about 0.01 to about 0.5 hours to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable increase in melt viscosity compared with the melt flow rate of the starting copolymer.
Claim 14
Dependent Claim
186 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery ethylene-vinyl acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate having a melt index of from 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provided that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen supplied as air at a temperature of from about 140° C., to about 225° C. at a pressure of from about 0.01 to about 10 atmospheres in the presence of from about 0.001 to about 5 parts by weight of an alkali metal, ammonium or zinc salt of a weak aliphatic carboxylic acid or aromatic carboxylic salt having a pK value in the range of from about 2 to about 6 as catalyst for from about 0.01 to about 0.5 hours to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable increase in melt viscosity compared with the melt flow rate of the starting copolymer.
Claim 15
Dependent Claim
12 words
The process of claim 12 in which the catalyst is sodium acetate.
Claim 16
Dependent Claim
146 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery ethylene-vinyl acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate having a melt index of from about 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provided that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen at elevated temperature in the presence of a catalytically effective amount of an alkali metal salt of an aliphatic carboxylic acid having a pK value in the range of from about 3 to about 10 for a period sufficient to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable decrease in melt flow rate compared with the melt flow rate of the starting copolymer.
Claim 17
Dependent Claim
146 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery ethylene-vinyl acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate having a melt index of from about 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provided that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen at elevated temperature in the presence of a catalytically effective amount of an alkali metal salt of an aliphatic carboxylic acid having a pK value in the range of from about 3 to about 10 for a period sufficient to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable decrease in melt flow rate compared with the melt flow rate of the starting copolymer.
Claim 18
Dependent Claim
182 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate having a melt index of from 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provided that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen supplied as air at a temperature of from about 140° C. to about 225° C. at a pressure of from about 0.01 to about 10 atmospheres in the presence of from about 0.001 to about 5 parts by weight of an alkali metal salt of an aliphatic carboxylic acid or aromatic carboxylic salt having a pK value in the range of from about 2 to about 6 as catalyst for from about 0.01 to about 0.5 hours to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable decrease in melt flow rate compared with the melt flow rate of the starting copolymers.
Claim 19
Dependent Claim
182 words
A process for toughening ethylene-vinyl acetate copolymers which comprises reacting a rubbery acetate copolymer containing from about 2 to about 75 weight percent combined vinyl acetate having a melt index of from 2 to about 40 and being derived from the copolymerization of ethylene and vinyl acetate with or without a third comonomer polymerizable with ethylene and vinyl acetate, it being provided that if such third comonomer is acidic, the resulting terpolymer is neutralized prior to the toughening process, with oxygen supplied as air at a temperature of from about 140° C. to about 225° C. at a pressure of from about 0.01 to about 10 atmospheres in the presence of from about 0.001 to about 5 parts by weight of an alkali metal salt of an aliphatic carboxylic acid or aromatic carboxylic salt having a pK value in the range of from about 2 to about 6 as catalyst for from about 0.01 to about 0.5 hours to provide an ethylene-vinyl acetate copolymer demonstrating an appreciable decrease in melt flow rate compared with the melt flow rate of the starting copolymers.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-05-21 | 1982-11-20 | 1983-05-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-05-21 | 1986-11-20 | 1987-05-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-05-21 | 1990-11-20 | 1991-05-22 | $7700.00 | Window Closed / Lapsed |