| 摘要 |
Self-extinguishing, flame-resistant expanded materials are obtained from compositions comprising a mixture of (a) an expandible resin, with (b) a polychlorinated diphenyl, said composition being capable of forming a polymeric spongy or expanded material which satisfies the A.S.T.M.: D.757-49 and D.635-56.T tests. The preferred diphenyl is decachlorodiphenyl; other flame-retardant additives, such as organic and inorganic antimony derivatives (e.g. antimony triphenyl, antimony tributyl and antimony lactate) may also be present in the composition. Suitable resins for use in the compositions are natural and synthetic rubber (e.g. butadiene - acrylonitrile rubber), either as solids or as latex; polystyrene, polyester-isocycnates, and polyethylene. Examples are given for preparation of the following compositions, with their subsequent foaming or expansion to yield flame-resistant polymer foams: (1) 200 parts by weight of 60% natural rubber latex, 5 parts of soap, and 300 parts of a dispersion (made up of decachlorodiphenyl, 1000 parts; antimony trioxide, 600 parts; and a sulphonated naphthonic acid wetting agent, 40 parts; dispersed in 660 parts of water) were mixed, and a sulphur vulcanizing agent added; the composition was foamed by beating, then gelled and vulcanized with heat, to give a flame-resistant foam rubber; (2) a polyester composition of an adipic acid-phthalic acid-triol polyester with an equal weight of decachlorodiphenyl was reacted with tolylene polyisocyanate, water, polyoxyethylene glycol and tri-n-butylamine to give a flame-resistant polyurethane foam; (3) an aqueous-ammonia suspension of a butadiene-acrylonitrile copolymer with the dispersion of Example 1 was beaten to a foam and vulcanized to give a flame-resistant synthetic rubber foam; (4) crushed polystyrene, decachlorodiphenyl, and azoisobutyric acid dinitrile were thoroughly mixed and expanded in a hot mould to give a rigid self-extinguishing foam. |
