| 摘要 |
1448402 Expandable styrene polymer/organic bromine compositions CHEMISCHE WERKE HULS AG 24 Jan 1974 [27 Jan 1973] 03317/74 Headings C3C and C3P An expandable styrene polymer (which may contain up to 50% by wt. of comonomer) composition comprises a blowing agent and as flame-retardant an organic bromine compound of formula R-CHBr-CH 2 -CBr 2 X, where X is Br or H and R is an optionally halogensubstituted C 1-16 aliphatic or C 6-10 aromatic radical which may be present in such amount that the bromine content relative to the polymer is either 0À1-5% by wt. or 0À05-0À7% by wt. if a synergist which is an organic peroxy or free-radical-forming compound is present (optionally with phosphorus and/or antimony compounds) in an amount of 0À05-1À0% by wt. In the examples polystyrene beads containing pentone, produced either by polymerizing styrene in an aqueous system in the presence of the pentane or by treating beads of polystyrene with pentane, are treated in aqueous suspension with the organic bromine compound, viz. 1,1,1,3-tetrabromononane, 1,1,1,3-tetrabromoheptane, 1,1,1,3 - tetrabromo - 3 - phenylpropane, 1,1,1,3,4,5 - hexabromopentane or 1,1,1,3,5,8,8,8 - octabromo-octane, with optionally dicumyl peroxide as synergist (in Example 3), and the treated beads are then optionally dried and foamed, e.g. with boiling water. |
