US4087486A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Polypropylene composition containing EPR
Assignee: BP Corp North America Inc
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Filing: 1975-05-15
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Granted: 1978-05-02
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Expires: 1995-05-15
Abstract
Abstract Polypropylene composition having improved knit-line properties comprising from 5 to 30 parts by weight of a saturated ethylene-propylene rubber, correspondingly 95 to 70 parts by weight crystalline homopolymeric polypropylene and from 0.01 to 0.2 parts by weight of an organic peroxide per each 100 parts by weight of the total concentration of saturated ethylene-propylene rubber and polypropylene.
Inventors
- 👤 Ivor R. Fielding
- 👤 Wassily Poppe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 05:04
CPC Classifications
C; C08; C08K; C08K5/00; C08K5/04; C08K5/14; C08L; C08L23/00; C08L23/02; C08L23/10; C08L23/12; C08L23/16
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
58 words
A polypropylene composition having improved knit-line properties comprising from 5 to 30 parts by weight of a saturated ethylene-propylene rubber, correspondingly 95 to 70 parts by weight crystalline homopolymeric polypropylene and from 0.01 to 0.2 parts by weight of an organic peroxide per each 100 parts by weight of the total concentration of saturated ethylene-propylene rubber and polypropylene.
Claim 2
Dependent Claim
58 words
A polypropylene composition having improved knit-line properties comprising from 5 to 30 parts by weight of a saturated ethylene-propylene rubber, correspondingly 95 to 70 parts by weight crystalline homopolymeric polypropylene and from 0.01 to 0.2 parts by weight of an organic peroxide per each 100 parts by weight of the total concentration of saturated ethylene-propylene rubber and polypropylene.
Claim 3
Dependent Claim
28 words
The composition of claim 1, wherein said ethylene-propylene rubber comprises from 75 to 30 percent by weight ethylene and correspondingly from 25 to 70 percent by weight propylene.
Claim 4
Dependent Claim
29 words
The composition of claim 1, wherein said peroxide has a half-life of about 1 to 30 seconds at a temperature in the range of about 400° to 525° F.
Claim 5
Dependent Claim
13 words
The composition of claim 3, wherein said peroxide comprises alpha, alpha'-bis (t-butylperoxy) diisopropylbenzene.
Claim 6
Dependent Claim
28 words
The process of forming molded parts having improved knit-line properties where two fronts meet which comprises molding the composition of claim 1 at about 400° to 525° F.
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) | 1981-05-01 | 1981-10-31 | 1982-05-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-01 | 1985-10-31 | 1986-05-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-01 | 1989-10-31 | 1990-05-02 | $7700.00 | Window Closed / Lapsed |