Claims
- 1. A thermoplastic (non-thermosetting) composition comprising (a) a normally flammable polyolefin resin and (b) a blend of (i) hydrated alumina, (ii) polydiorganosiloxane and (iii) polyphenylene oxide, said blend being present in an amount effective to improve the flame resistance of the polyolefin resin.
- 2. The composition of claim 1 wherein the alumina and polyphenylene oxide are present in a ratio of between 30:1 and 5:1 by weight.
- 3. The composition of claim 2, wherein the blend and resin are present in a ratio of between about 1:1 and 3:1 by weight.
- 4. The composition of claim 1 wherein the polyolefin is polypropylene.
- 5. The composition of claim 1 wherein the polyolefin is polyethylene.
- 6. The composition of claim 1 wherein the polyolefin is ethylene-propylene copolymer.
- 7. The composition of claim 1 wherein the alumina comprises from about 50 to 70%, the polydiorganosiloxane comprises from about 0.1 to 6%, and the polyphenylene oxide comprises from about 0.5 to 18% by total weight of the thermoplastic composition.
- 8. The composition of claim 1 wherein the alumina comprises from about 50 to 65%, the polydiorganosiloxane comprises from about 0.5 to 4%, and the polyphenylene oxide comprises from about 2 to 9% by total weight of the thermoplastic composition.
- 9. The composition of claim 1, which includes a lead salt.
- 10. The composition of claim 1, which includes a lead phthalate.
- 11. The composition of claim 1, in which the polydiorganosiloxane is polydimethylsiloxane.
- 12. The composition of claim 11, in which the polydimethylsiloxane is a fluid.
- 13. The composition of claim 1, in which the hydrated alumina has a median particle size of less than 60 microns in diameter.
- 14. The composition of claim 13, in which the median particle size of the alumina is between about 1 and 40 microns in diameter.
- 15. The composition of claim 1, which includes a styrene-butadiene-styrene block copolymer.
- 16. A thermoplastic composition comprising a normally flammable polyolefin resin selected from the group consisting of polyethylene, polypropylene and ethylene-propylene copolymers, and a flame resistance improving amount of a blend of hydrated alumina, polydimethylsiloxane and polyphenylene oxide, said composition also including dibasic lead phthalate.
Parent Case Info
This is a continuation of application Ser. No. 111,961 filed Jan. 14, 1980, now abandoned.
US Referenced Citations (7)
Foreign Referenced Citations (2)
Number |
Date |
Country |
2439490 |
Mar 1975 |
DEX |
50-1141 |
Jan 1975 |
JPX |
Continuations (1)
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Number |
Date |
Country |
Parent |
111961 |
Jan 1980 |
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