US4188432A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Articles resistant to attack by fatty substances, made from polystyrene blends, and compositions
Assignee: Shell USA Inc
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Filing: 1978-03-30
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Granted: 1980-02-12
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Expires: 1998-03-30
Abstract
Abstract Shaped articles which are resistant to attack by fatty substances and chemicals and which have impact resistance comparable to high impact polystyrene are produced by extrusion or injection molding of a composition consisting essentially of high impact styrene-butadiene graft copolymer or a mixture thereof with no more than about 55% styrene homopolymer and small proportions of polyethylene or polypropylene and of a block copolymer X-Y-X in which each X is a polystyrene block of about 5,000 to 10,000 molecular weight and Y is a hydrogenated polybutadiene block of 25,000 to 50,000 molecular weight. The articles are characterized by having a skin which is substantially enriched in polyolefin.
Inventors
- 👤 Geoffrey Holden
- 👤 Lam H. Gouw
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 22:54
CPC Classifications
C; C08; C08L; C08L25/00; C08L25/02; C08L25/04; C08L25/06; C08L51/00; C08L51/04; C08L23/00; C08L23/02; C08L23/04; C08L53/00; C08L53/02; Y; Y10; Y10T; Y10T428/00; Y10T428/13; Y10T428/1352; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31917; Y10T428/31931
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
169 words
An article resistant to attack by fatty substances, produced by extrusion or injection molding from a composition consisting essentially of (A) 60 to 93 parts by weight, per 100 parts of the compositions, of a polystyrene component consisting of 100 to about 45% of a thermoplastic styrene-diolefin elastomer graft copolymer with 0 to about 55% of thermoplastic styrene homopolymer; (B) 2 to 30 parts by weight, per 100 parts of the composition, of a polyolefin component selected from the group consisting of low density polyethylene, high density polyethylene and polypropylene and (C) 5 to 20 parts by weight, per 100 parts of the composition, of a block copolymer X-Y-X where each X is a polystyrene block of about 5,000 to 10,000 molecular weight and Y is a hydrogenated polybutadiene block of about 25,000 to 50,000 molecular weight, the total molecular weight of the block copolymer being less than about 60,000. said article being characterized by having a skin layer substantially enriched in polyolefin, which imparts resistance to fatty substances.
Claim 2
Dependent Claim
169 words
An article resistant to attack by fatty substances, produced by extrusion or injection molding from a composition consisting essentially of (A) 60 to 93 parts by weight, per 100 parts of the compositions, of a polystyrene component consisting of 100 to about 45% of a thermoplastic styrene-diolefin elastomer graft copolymer with 0 to about 55% of thermoplastic styrene homopolymer; (B) 2 to 30 parts by weight, per 100 parts of the composition, of a polyolefin component selected from the group consisting of low density polyethylene, high density polyethylene and polypropylene and (C) 5 to 20 parts by weight, per 100 parts of the composition, of a block copolymer X-Y-X where each X is a polystyrene block of about 5,000 to 10,000 molecular weight and Y is a hydrogenated polybutadiene block of about 25,000 to 50,000 molecular weight, the total molecular weight of the block copolymer being less than about 60,000. said article being characterized by having a skin layer substantially enriched in polyolefin, which imparts resistance to fatty substances.
Claim 3
Dependent Claim
6 words
Extruded sheet according to claim 1.
Claim 4
Dependent Claim
10 words
Hollow articles produced from extruded sheet according to claim 2.
Claim 5
Dependent Claim
7 words
Injection molded article according to claim 1.
Claim 6
Dependent Claim
148 words
A composition adapted to production of the articles of claim 1 by extrusion or injection molding, consisting essentially of (A) 60 to 93 parts by weight, per 100 parts of the compositions, of a polystyrene component consisting of 100 to about 45% of a thermoplastic styrene-diolefin elastomer graft copolymer with 0 to about 55% of thermoplastic styrene homopolymer; (B) 2 to 30 parts be weight, per 100 parts of the composition, of polyolefin component selected from the group consisting of low density polyethylene, high density polyethylene and polypropylene and (C) 5 to 20 parts be weight, per 100 parts of the composition, of a block copolymer X-Y-X where each X is a polystyrene block of about 5,000 to 10,000 molecular weight and Y is a hydrogenated polybutadiene block of about 25,000 to 50,000 molecular weight, the total molecular weight of the block copolymer being less than about 60,000.
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) | 1983-02-11 | 1983-08-13 | 1984-02-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-02-11 | 1987-08-13 | 1988-02-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-02-11 | 1991-08-13 | 1992-02-12 | $7700.00 | Window Closed / Lapsed |