US3966675A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermal stabilizers for polypropylene
Assignee: Wyeth Holdings LLC
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Filing: 1974-11-11
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Granted: 1976-06-29
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Expires: 1994-11-11
Abstract
Abstract Mixtures of pentaerythritol tetrakis(3-n-dodecylthiopropionate) and either bis(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiolterephthalate or 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-triazine-2,4,6-(1H,3H,5H)-trione are extremely useful for inhibiting thermal degradation of polypropylene.
Inventors
- 👤 Edward Joseph Schurdak
- 👤 Christos Savides
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 08:27
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/16; C08K5/34; C08K5/3467; C08K5/3477; C08K5/3492; C08K5/0008; C08K5/005
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
27 words
A stabilizer composition useful in the synergistic enhancement of the resistance of polypropylene to thermal degradation comprising, in combination, pentaerythritol tetrakis(3-n-dodecylthiopropionate) and either bis(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiolterephthalate or 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-triazine-2,4,6-(1H,3H,5H)-trione.
Claim 2
Dependent Claim
27 words
A stabilizer composition useful in the synergistic enhancement of the resistance of polypropylene to thermal degradation comprising, in combination, pentaerythritol tetrakis(3-n-dodecylthiopropionate) and either bis(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiolterephthalate or 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-triazine-2,4,6-(1H,3H,5H)-trione.
Claim 3
Dependent Claim
15 words
A composition comprising polypropylene and a stabilizing amount of the stabilizer composition of claim 1.
Claim 4
Dependent Claim
32 words
A stabilizer composition as defined in claim 1 wherein the weight ratio of said bis(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiolterephthalate or 1,3,5-tris(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-triazine-2,4,6-(1H, 3H, 5H)-trione or mixtures thereof to said pentaerythritol tetrakis(3-n-dodecylthiopropionate) is between 2:1 and 1:10.
Claim 5
Dependent Claim
15 words
A composition comprising polypropylene and a stabilizing amount of the stabilizer composition of claim 3.
Claim 6
Dependent Claim
45 words
A composition as defined in claim 2 wherein said stabilizing amount comprises 0.02 to 1 percent, on weight of polypropylene, of said bis(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl) dithiolterephthalate or said 1,3,5-tris-(4-t-butyl-3-hydroxy-2,6-dimethylbenzyl)-s-triazine-2,4,6-(1H, 3H, 5H)-trione or mixtures thereof and 0.1 to 1 percent, on weight of polypropylene, of said pentaerythritol tetrakis(3-n-dodecylthiopropionate).
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) | 1979-06-29 | 1979-12-29 | 1980-06-29 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-06-29 | 1983-12-29 | 1984-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-06-29 | 1987-12-29 | 1988-06-29 | $7700.00 | Window Closed / Lapsed |