polymerized stirolici expand from finely divided, with brief tempe of minimum sosra into the mold.

摘要

Particulate expandable styrene polymers having short minimum molding times which are coated with from 0.005 to 0.5% by weight, based on the expandable styrene polymer, of a mono- and/or poly-urethane melting below 150 DEG C. and obtained by reaction of I (a) aliphatic, cycloaliphatic, aliphatic-cycloaliphatic, araliphatic and aromatic mono- and/or poly-isocyanates with (b) linear or branched monoalcohols of from 2 to 24 carbon atoms which may or may not be olefinically unsaturated and/or halogenated, or mixtures of such monoalcohols and (c) optionally dihydric to tetrahydric alcohols, the ratio of NCO groups to the total number of hydroxyl groups being from 0.25 to approximately 1:1 and the molar ratio of dihydric to tetrahydric alcohols (if used) to polyisocyanates being not more than 0.4:1; or reaction of II (a) linear or branched aliphatic, cycloaliphatic, aliphatic-cycloaliphatic, araliphatic or aromatic chlorocarboxylates of from 2 to 24 carbon atoms in the alcohol radical, which may or may not be olefinically unsaturated and/or halogenated, with (b) aliphatic, cycloaliphatic, aliphatic-cycloaliphatic, araliphatic and aromatic mono- and/or poly-amines, the ratio of amino groups in the mono- and/or poly-amines to chlorocarboxylates being from 2:1 to 1:1.