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US5037914A
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Process for preparing tetrafluoroethylene-ethylene copolymers
Assignee: Syensqo Specialty Polymers Italy SpA
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Filing: 1989-11-17
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Granted: 1991-08-06
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Expires: 2009-11-17
Abstract
Abstract The present invention relates to a process for preparing copolymers of tetrafluoroethylene with ethylene, and optionally with a third monomer, of vinylic character. The process is characterized in that tetrafluoroethylene is caused to react with ethylene and with the optional third, vinylic, monomer in an aqueous emulsion with the aid of a polymerization initiator of peroxy type, at a temperature within the range between 30° and 95° C. and under a pressure within the range of from 1.5 to 4.0 MPa, in the presence of tert.-butyl alcohol and of 1,1,2,2-tetrachloro-1,2-difluoroethane.
Inventors
- 👤 Claudio Monti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 10:56
CPC Classifications
C; C08; C08F; C08F214/00; C08F214/18; C08F214/26; C08F214/265; C08F14/00; C08F14/18; C08F14/26; C08F210/00; C08F210/02; C08F2438/00; C08F2438/01
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
69 words
A process for preparing copolymers of tetrafluoroethylene with ethylene and possibly with a third monomer, of vinylic character, comprising reacting tetrafluoroethylene with ethylene in an aqueous emulsion with the aid of a peroxy polymerization initiator at a temperature within the range of from 30° to 95° C. and under a pressure within the range of from 1.5 to 4.0 MPa, in the presence of tert.-butyl alcohol and of 1,1,2,2-tetrachloro-1,2-difluoroethane.
Claim 2
Dependent Claim
69 words
A process for preparing copolymers of tetrafluoroethylene with ethylene and possibly with a third monomer, of vinylic character, comprising reacting tetrafluoroethylene with ethylene in an aqueous emulsion with the aid of a peroxy polymerization initiator at a temperature within the range of from 30° to 95° C. and under a pressure within the range of from 1.5 to 4.0 MPa, in the presence of tert.-butyl alcohol and of 1,1,2,2-tetrachloro-1,2-difluoroethane.
Claim 3
Dependent Claim
21 words
The process according to claim 1, wherein the reaction of tetrafluoroethylene with ethylene further includes a third monomer of vinylic character.
Claim 4
Dependent Claim
16 words
The process according to claim 2, wherein the third vinyl monomer is a fluorinated vinyl monomer.
Claim 5
Dependent Claim
29 words
The process according to claim 1, wherein the amount of tert.-butyl alcohol is within the range of from 10 to 60 g per each kg of liquid reaction mixture.
Claim 6
Dependent Claim
29 words
The process according to claim 4, wherein the amount of tert.-butyl alcohol is within the range of from 10 to 35 g per each kg of liquid reaction mixture.
Claim 7
Dependent Claim
28 words
The process according to claim 1, wherein the amount of 1,1,2,2-tetrachloro-1,2-difluoroethane is within the range of from 15 to 75 g per each kg of liquid reaction mixture.
Claim 8
Dependent Claim
28 words
The process according to claim 6, wherein the amount of 1,1,2,2-tetrachloro-1,2-difluoroethane is within the range of from 20 to 70 g per each kg of liquid reaction mixture.
Claim 9
Dependent Claim
13 words
The process according to claim 1 wherein the reaction medium also contains 1,1,2-trichloro-1,2,2-trifluoroethane.
Claim 10
Dependent Claim
23 words
The process according to claim 8, wherein the weight ratio of 1,1,2-trichloro-1,2,2-trifluoroethane to 1,1,2,2-tetrachloro-1,2-difluoroethane is within the range of from 0.2 to 1.5.
Claim 11
Dependent Claim
24 words
The process according to claim 1, wherein the reaction is carried out at a temperature within the range of from 65° to 80° C.
Claim 12
Dependent Claim
24 words
The process according to claim 1, wherein the reaction is carried out at a pressure within the range of from 2.0 to 2.5 MPa.
Claim 13
Dependent Claim
49 words
The process according to claim 2, wherein the copolymer of tetrafluoroethylene with ethylene and with a third vinyl monomer contains from 40 to 60 mole % of tetrafluoroethylene and from 40 to 60 mole % of ethylene, and from 0 to 10 mole % of the third vinyl monomer.
Claim 14
Dependent Claim
15 words
Copolymers comprising tetrafluoroethylene with ethylene obtained according to the process of claims 1 or 2.
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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) | 1994-08-05 | 1995-02-04 | 1995-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-08-05 | 1999-02-04 | 1999-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-08-05 | 2003-02-04 | 2003-08-06 | $7700.00 | Window Closed / Lapsed |