| 摘要 |
<p>Expansible polystyrene particles contain 1 wt. %, pref. 0.05-0.2 wt. % of cpd(s) of formula (I) and/or (II) where A is -O- or -COO-. When A is -O-, R2 and R3 are opt. halogen substd. (cycloalkyl or phenyl; R5 is 4-30C alkyl or a (partly)halogenated 9-30C alkyl; X is halogen or opt. halogenated 1-8C alkyl; R1 and R4 are opt. halogenated 1-30C alkyl, except that when R2 and R3 are alkyl, X is Br and m is 2, R1 and R4 are non-halogenated 1-30C alkyl or (partly)halogenated 9-30C alkyl. When A is -COO-; R1, R4 and R5 are indep. opt. halogen substd. 1-30C alkyl; R2 and R3 are indep. opt. halogen substd. (cyclo)alkyl or phenyl and X is halogen or 1-8C alkyl. In both cases m is 0-4 and n is 0-5. The particles give mouldings of homogeneous structure and fine cells, with shrinkage 1% and moisture content 0.3%. No disagreeable odour is emitted during pre-expansion of the particles and residence time in the mould during cooling is reduced.</p> |
