US3853970A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vinyl chloride graft polymers and process for preparation thereof
Assignee: Diamond Shamrock Plastics Corp
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Filing: 1973-08-03
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Granted: 1974-12-10
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Expires: 1993-08-03
Abstract
Abstract A graft copolymer is described which contains, by weight, from about 60% to 95% of polymerized vinyl chloride and from 5% to 40% of an ethylene/vinyl acetate copolymer backbone which, in turn, contains from 10% to 40%, by weight, of polymerized vinyl acetate. This graft copolymer is thermally stable and has both good physical properties and vastly improved processing characteristics, particularly for injection molding operations. The copolymer is prepared in aqueous suspension at polymerization temperatures ranging from 90* C to 165* C employing a suitable, monomer-soluble, free-radical type initiator which is injected into the reaction mixture at a prescribed rate throughout the reaction.
Inventors
- 👤 J Dietrich
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 09:15
CPC Classifications
C; C08; C08F; C08F255/00; C08F255/02; C08F255/026
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
123 words
A PROCESS FOR PREPARING AN EASILY PROCESSED GRAFT COPOLYMER OF VINYL CHLORIDE ON A PREFORMED ETHYLENE/VINYL ACETATE COPOLYMER WHICH COMPRISES REACTING IN AN AQUEOUS SUSPENDING MEDIUM FOR A TIME PERIOD OF FROM 1 TO 12 HOURS A MIXTURE CONTAINING, BY WEIGHT, FROM 60% TO 95% OF VINYL CHLORIDE MONOMER AND FROM 5% TO 40% OF A PREFORMED ETHYLENE/VINYL ACETATE COPOLYMER AT A TEMPERATURE OF 90-165* C, WHILE INJECTING A MONOMER-SOLUBLE FREE-RADICAL TYPE POLYMERIZATION INITIATOR AT A PRESECRIBED RATE INTO THE REACTION MIXTURE DURING THE REACTION, SAID PREFORMED ETHYLENE/VINYL ACETATE COPOLYMER CONTAINING, BY WEIGHT, FROM 10% TO 40% POLYMERIZED VINYL ACETATE AND HAVING AN INHERENT VISCOSITY OF 0.50 TO 1.50 AS MEASURED AS 30* EMPLOYING A SOLUTION CONTAINING 0.25 G OF COPOLYMER IN TOLUENE.
Claim 2
Dependent Claim
123 words
A PROCESS FOR PREPARING AN EASILY PROCESSED GRAFT COPOLYMER OF VINYL CHLORIDE ON A PREFORMED ETHYLENE/VINYL ACETATE COPOLYMER WHICH COMPRISES REACTING IN AN AQUEOUS SUSPENDING MEDIUM FOR A TIME PERIOD OF FROM 1 TO 12 HOURS A MIXTURE CONTAINING, BY WEIGHT, FROM 60% TO 95% OF VINYL CHLORIDE MONOMER AND FROM 5% TO 40% OF A PREFORMED ETHYLENE/VINYL ACETATE COPOLYMER AT A TEMPERATURE OF 90-165* C, WHILE INJECTING A MONOMER-SOLUBLE FREE-RADICAL TYPE POLYMERIZATION INITIATOR AT A PRESECRIBED RATE INTO THE REACTION MIXTURE DURING THE REACTION, SAID PREFORMED ETHYLENE/VINYL ACETATE COPOLYMER CONTAINING, BY WEIGHT, FROM 10% TO 40% POLYMERIZED VINYL ACETATE AND HAVING AN INHERENT VISCOSITY OF 0.50 TO 1.50 AS MEASURED AS 30* EMPLOYING A SOLUTION CONTAINING 0.25 G OF COPOLYMER IN TOLUENE.
Claim 3
Dependent Claim
42 words
The process of claim 1 wherein the polymerization reaction mixture contains, by weight, from 75% to 85% vinyl chloride monomer and from 15% to 25% preformed ethylene/vinyl acetate copolymer which contains, in turn, from 15% to 30% polymerized vinyl acetate, by weight.
Claim 4
Dependent Claim
30 words
The process of claim 1 which is conducted under sufficient pressUre as supplied by incremental injection of water into the reactor to provide substantially liquid-full reactor conditions throughout the reaction.
Claim 5
Dependent Claim
11 words
The process of claim 3 which is completed in 1-3 hours.
Claim 6
Dependent Claim
23 words
The process of claim 1 wherein from 0.01% to 2.0% initiator is employed, based on the total weight of the vinyl chloride monomer.
Claim 7
Dependent Claim
83 words
The graft copolymer produced by the process of claim 1 which contains, by weight, from about 60% to 95% of polymerized vinyl chloride and from about 5% to 40% of an ethylene/vinyl acetate copolymer containing, by weight, from 10% to 40% polymerized vinyl acetate, said graft copolymer product exhibiting a melt viscosity no greater than 9 X 104 poises at 180* C and no greater than 1 X 104 poises at 210* C when measured at a shear rate of 10 sec 1.
Claim 8
Dependent Claim
43 words
The graft copolymer product of claim 6 which contains, by weight, from about 75% to 85% of polymerized vinyl chloride and from about 15% to 25% of an ethylene/vinyl acetate copolymer which contains from 15% to 30% of polymerized vinyl acetate, by weight.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-09 | 1978-06-10 | 1978-12-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-09 | 1982-06-10 | 1982-12-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-09 | 1986-06-10 | 1986-12-10 | $7700.00 | Window Closed / Lapsed |