Foamable Vinylaromatic Polymers

摘要

1,166,527. Moulding foamed articles. MONSANTO CHEMICALS Ltd. 30 May, 1968 [7 July, 1967], No. 31349/67. Heading B5A. [Also in Divisions B2 and C3] A foamed vinyl aromatic polymer article is produced by preparing a prefoam of foamed particles by steam-heating particles comprising a vinylaromatic polymer, a volatile blowing agent and a primary amide of m.p. 35-115‹ C. and of formula RCONHR1, where R is a C 10-24 aliphatic hydrocarbon radical and R1 is H or a C 1-3 alkyl radical, and treating the prefoam with steam in a mould to produce the required article, e.g. a box in Example 1 and a block in Example 3.