Patent US3870680A successfully refreshed from Google Patents.
US3870680A
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US
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Copper inhibitors for polyolefins
Assignee: Individual
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Filing: 1973-10-19
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Granted: 1975-03-11
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Expires: 1993-10-19
Abstract
Abstract Compounds of the formula WHEREIN R1, R2, R3, and R4 are each branched-chain alkyl of 3-8 carbon atoms, preferably t-butyl, are novel compounds, useful in combination with hindered-phenol antioxidants, for inhibiting high temperature degradation of polyolefins, especially polypropylene, in contact with copper as metal, alloys, oxides, or salts. These novel compounds can be prepared by (a) reacting a p-hydroxybenzoic acid with thionyl chloride to form a benzoyl chloride and then (b) reacting such benzoyl chloride with hydrazine.
Inventors
- 👤 Edward Schurdak
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 22:57
CPC Classifications
C; C07; C07C; C07C243/00; C07C243/24; C07C243/38; C08; C08K; C08K5/00; C08K5/04; C08K5/13; C08K5/16; C08K5/22; C08K5/24; C08K5/25
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
42 words
10. POLYPROPYLENE STABILIZED AGAINST COPPER-CATALYZED THERE MAL DEGRADATION BY THE COMBINATION OF (A) AN AMOUNT OF A HINDERED-PHENOL ANTIOXIDANT SUFFICIENT TO STABILIZE SAID POLYPROPYLENE AGAINST THERMAL DEGRADATION IN THE ABSENCE OF COPPER AND (B) AN AMOUNT OF A COMPOUND OF THE FORMULA
Claim 2
Dependent Claim
42 words
10. POLYPROPYLENE STABILIZED AGAINST COPPER-CATALYZED THERE MAL DEGRADATION BY THE COMBINATION OF (A) AN AMOUNT OF A HINDERED-PHENOL ANTIOXIDANT SUFFICIENT TO STABILIZE SAID POLYPROPYLENE AGAINST THERMAL DEGRADATION IN THE ABSENCE OF COPPER AND (B) AN AMOUNT OF A COMPOUND OF THE FORMULA
Claim 3
Dependent Claim
29 words
A stabilizer composition useful in the enhancement of the resistance of polyolefins to copper-catalyzed thermal degradation comprising, in combination, a hindered phenol antioxidant and a compound of the formula
Claim 4
Dependent Claim
29 words
A stabilizer composition useful in the enhancement of the resistance of polyolefins to copper-catalyzed thermal degradation comprising, in combination, a hindered phenol antioxidant and a compound of the formula
Claim 5
Dependent Claim
12 words
A composition as defined in claim 1 wherein said compound is N,N''-bis(3,5-di-t-butyl-4-hydroxybenzoyl)hydrazine.
Claim 6
Dependent Claim
14 words
A composition as defined in claim 2 wherein said hindered-phenol antioxidant is pentaerythrityl tetrakis-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate.
Claim 7
Dependent Claim
13 words
A composition as defined in claim 2 wherein said hindered-phenol antioxidant is 1,3,5-trimethyl-2,4,6-tris)3,5-di-t-butyl-4-hydroxybenzyl)benzene.
Claim 8
Dependent Claim
14 words
A composition as defined in claim 1 wherein said hindered-phenol antioxidant is pentaerythrityl tetrakis-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate.
Claim 9
Dependent Claim
16 words
A composition comprising a polyolefin and a stabilizing amount of the stabilizer composition of claim 1.
Claim 10
Dependent Claim
12 words
A composition as defined in claim 6 wherein said polyolefin is polypropylene.
Claim 11
Dependent Claim
16 words
A composition comprising a polyolefin and a stabilizing amount of the stabilizer composition of claim 2.
Claim 12
Dependent Claim
12 words
A composition as defined in claim 8 wherein said polyolefin is polypropylene.
Claim 13
Dependent Claim
40 words
Polypropylene stabilized against copper-catalyzed thermal degradation by the combination of (a) an amount of a hindered-phenol antioxidant sufficient to stabilize said polypropylene against thermal degradation in the absence of copper and (b) an amount of a compound of the formula
Claim 14
Dependent Claim
40 words
Polypropylene stabilized against copper-catalyzed thermal degradation by the combination of (a) an amount of a hindered-phenol antioxidant sufficient to stabilize said polypropylene against thermal degradation in the absence of copper and (b) an amount of a compound of the formula
References Cited (Backward Citations)
US3772245A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |