Patent US5013790A successfully refreshed from Google Patents.
US5013790A
Expired / Lapsed
US
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Polymer blends of tapered styrene-butadiene triblock thermoplastic elastomers
Assignee: Dow Chemical Co
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Filing: 1989-07-05
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Granted: 1991-05-07
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Expires: 2009-07-05
Abstract
Abstract A thermoplastic blend useful for the preparation of molded articles comprising a thermoplastic polymer and a tapered triblock elastomer of a monovinylidene aromatic monomer and butadiene having a melt index (condition 200/5.0 ASTM method D1238-82) of 0.5 to 60 and an average molecular weight from 50,000 to 135,000.
Inventors
- 👤 Lu H. Tung
- 👤 Joseph J. Randazzo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 15:46
CPC Classifications
C; C08; C08F; C08F236/00; C08F236/02; C08F236/04; C08F236/10; C08F297/00; C08F297/02; C08F297/04; C08F297/042; C08L; C08L101/00; C08L51/00; C08L51/04; C08L53/00; C08L53/02
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
114 words
A thermoplastic blend comprising: (1) a thermoplastic polymer; and (2) a tapered triblock elastomer of the formula A-B-A wherein B is a polymer of butadiene and each A block is a polymer of a monovinylidene aromatic monomer and at least one junction between the A and B blocks is tapered so as to include in copolymerized form increasing amounts of butadiene toward B block, said tapered triblock elastomer having a ratio of monovinylidene aromatic monomer:butadiene of 10:90 to 40:60 a melt index (condition 200/5.0 ASTM method D1238-82) of 0.5 to 60; and an average molecular weight Mw of 50,000-150,000; the quantity of component (2) being sufficient to improve the impact resistance of the blend.
Claim 2
Dependent Claim
114 words
A thermoplastic blend comprising: (1) a thermoplastic polymer; and (2) a tapered triblock elastomer of the formula A-B-A wherein B is a polymer of butadiene and each A block is a polymer of a monovinylidene aromatic monomer and at least one junction between the A and B blocks is tapered so as to include in copolymerized form increasing amounts of butadiene toward B block, said tapered triblock elastomer having a ratio of monovinylidene aromatic monomer:butadiene of 10:90 to 40:60 a melt index (condition 200/5.0 ASTM method D1238-82) of 0.5 to 60; and an average molecular weight Mw of 50,000-150,000; the quantity of component (2) being sufficient to improve the impact resistance of the blend.
Claim 3
Dependent Claim
21 words
A thermoplastic blend according to claim 1 wherein the thermoplastic polymer is polystyrene, styrene acrylonitrile copolymer, or rubber modified derivatives thereof.
Claim 4
Dependent Claim
16 words
A thermoplastic blend according to claim 2 wherein the thermoplastic polymer is a high impact polystyrene.
Claim 5
Dependent Claim
13 words
A thermoplastic blend according to claim 1 additionally comprising an ignition resistant additive.
Claim 6
Dependent Claim
16 words
A thermoplastic blend according to claim 1 wherein the tapered triblock elastomer comprises styrene and butadiene
Claim 7
Dependent Claim
26 words
A thermoplastic blend according to claim 1 wherein the tapered triblock elastomer has an average molecular weight of from greater than 55,000 and less than 120,000.
Claim 8
Dependent Claim
14 words
A thermoplastic blend according to claim 1 comprising about 5 weight percent component (2).
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) | 1994-05-06 | 1994-11-05 | 1995-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-06 | 1998-11-05 | 1999-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-05-06 | 2002-11-05 | 2003-05-07 | $7700.00 | Window Closed / Lapsed |