| 摘要 |
<p>Disclosed is a flame retardant thermoplastic elastomeric composition that in the form of an insulation about an electrical conductor is able to meet or exceed the requirements of UL VW-1 Vertical Flame Test and in the form of a jacket about an electrical cable is able to meet or exceed the requirements of IEEE-383 Cable Tray Flame Test while having a limiting oxygen index of only 24 to 27 percent. The composition has an elastomeric component of the type comprising about 25 to about 75 parts by weight of a crystalline olefin resin and about 75 to about 25 parts by weight of a vulcanized monoolefin copolymer rubber comprising a polymer of ethylene or propylene and one other alpha olefin of the formula CH2=CHR where R is an alkyl of 1-12 carbon atoms. The composition includes a non-elastomeric component comprising blending about 20 to about 40 parts by weight of a flame retardant compound and about 5 to about 20 parts by weight of antimony oxide and about 0.01 to about 8 parts by weight of lead stabilizer to 100 parts by weight of the elastomeric component. The flame retardant compound is a chlorinated or brominated or chlorobrominated compound or mixtures thereof having a halogen content of from about 50% to about 85% by weight of the compound and the lead stabilizer is selected from the group consisting of lead oxide, lead stearate, lead fumarate and lead phthalate stabilizers. The composition may include other additives including from about 1 to about 20 parts by weight of an olefinic polymer and up to about 250 parts by weight of extender oil to 100 parts by weight of the elastomeric component.</p> |
