Patent US4213892A successfully refreshed from Google Patents.
US4213892A
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Process for preparing oxidatively-stable polymers by reaction with antioxidant in the presence of free radical
Assignee: Individual
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Filing: 1975-03-05
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Granted: 1980-07-22
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Expires: 1995-03-05
Abstract
Abstract Polymers are rendered more oxidatively stable by reaction with an antioxidant or stabilizer, generally a vinyl-group- or thiol group-containing antioxidant, in the presence of a free radical which may be produced by a redox system or ultra-violet light. The resulting polymers can be used as such or can be used as additives in other polymers to stabilize the latter.
Inventors
- 👤 Gerald Scott
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 13:41
CPC Classifications
C; C08; C08F; C08F291/00; C08C; C08C19/00; C08G; C08G85/00; C08G85/004; C08J; C08J7/00; C08J7/12; C08J7/123
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
111 words
A process for preparing an oxidatively stable polymer which comprises reacting the polymer with an antioxidant of the formula: ##STR16## in which R 1 and R 2 each independently represents a hydrogen atom or a tertiary alkyl radical such that at least one represents a tertiary alkyl radical and R 3 represents a hydrogen atom or an alkyl, hydroxy, hydroxyalkyl, alkoxyalkyl or mercaptoalkyl radical, said R radicals optionally being substituted by aromatic phenolic or aromatic amine groups, in the presence of a free radical with the proviso that when the free radical is produced by a free radical generator, said generator produces free radicals at a temperature below about 120° C.
Claim 2
Dependent Claim
111 words
A process for preparing an oxidatively stable polymer which comprises reacting the polymer with an antioxidant of the formula: ##STR16## in which R 1 and R 2 each independently represents a hydrogen atom or a tertiary alkyl radical such that at least one represents a tertiary alkyl radical and R 3 represents a hydrogen atom or an alkyl, hydroxy, hydroxyalkyl, alkoxyalkyl or mercaptoalkyl radical, said R radicals optionally being substituted by aromatic phenolic or aromatic amine groups, in the presence of a free radical with the proviso that when the free radical is produced by a free radical generator, said generator produces free radicals at a temperature below about 120° C.
Claim 3
Dependent Claim
18 words
A process according to claim 1 in which the polymer is reacted as an aqueous emulsion or latex.
Claim 4
Dependent Claim
13 words
A process according to claim 1 in which the polymer is ethylenically unsaturated.
Claim 5
Dependent Claim
15 words
A process according to claim 1 which is carried out in the absence of oxygen.
Claim 6
Dependent Claim
17 words
A process according to claim 1 in which the tertiary alkyl radical is a tertiary butyl radical.
Claim 7
Dependent Claim
12 words
A process according to claim 5 in which the antioxidant is 3,5-di-tert-butyl-4-hydroxybenzylmercaptan.
Claim 8
Dependent Claim
21 words
A polymer composition which comprises a polymer and an oxidatively stable polymer obtained by a process as defined in claim 1.
Claim 9
Dependent Claim
17 words
A process according to claim 1 in which the free raidcal is produced by a redox system.
Claim 10
Dependent Claim
17 words
A process according to claim 1 in which the free radical is produced by an azo system.
Claim 11
Dependent Claim
17 words
A process according to claim 1 in which the free radical is produced by ultra-violet light activation.
Claim 12
Dependent Claim
23 words
A process according to claim 1 in which the polymer is a polyethylene containing residual unsaturation and the antioxidant is a thiol-containing antioxidant.
References Cited (Backward Citations)
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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) | 1983-07-22 | 1984-01-21 | 1984-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-07-22 | 1988-01-21 | 1988-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-07-22 | 1992-01-21 | 1992-07-22 | $7700.00 | Window Closed / Lapsed |