Process for the production of Foamed Materials

1,160,475. Foamed unsaturated polyesters. FARBENFABRIKEN BAYER A.G. 21 July, 1967 [21 July, 1966], No. 33663/67. Headings C3C and C3P. Foamed materials are prepared by foaming a copolymerizable mixture comprising an unsaturated polyester which is a polycondensation product of an ethylene 1,2-dicarboxylic acid or anhydride thereof and a polyhydric alcohol, and a monomeric polymerizable vinyl, vinylidene or allyl compound by adding to the copolymerizable mixture (a) a polymerization catalyst system comprising an organic peroxide as catalyst and an accelerator adapted to reduce the temperature of the activity of the catalyst to ambient temperature; (b) a carbonic acid ester anhydride which decomposes with splitting off of carbon dioxide; and (c) a primary secondary or tertiary amine in which the substituent groups are alkyl, cycloalkyl, alkenyl or alkaryl (wherein the alkyl groups may carry a hydroxyl group or a keto group) and in which the nitrogen atom may form part of a heterocyclic ring, a quaternary ammonium base derived from such an amine, or a primary or secondary N-monoarylamine, in amounts of 1 to 70% by weight, referred to the amount of carbonic acid ester anhydride present, said amine reducing the decomposition temperature of the carbonic acid ester anhydride (b) to ambient temperature. The term " carbonic acid ester anhydride " means an anhydride of a monoester of carbonic acid, and includes anhydrides of carbonic acid monoesters with each other as well as mixed anhydrides formed from one or more molecules of a carbonic acid monoester and one or more molecules of another acid. In the examples are used polyesters prepared from maleic anhydride, phthalic anhydride, 1,3-butanediol, diglycol, castor oil, fumaric acid, hexachloroendomethylene-tetrahydrophthalic acid, glycol, and 1,2-propanediol; styrene; hydroquinone, toluhydroquinone; benzoyl peroxide, cyclohexanone peroxide, cobalt naphthenate; organosiloxane-hydroxyalkylene copolymer, sodium salt of sulphonated castor oil in water; dimethyl aniline; expanded clay, glass fibre and many carbonic acid ester anhydrides (b) and amines (c).