摘要 |
<p>The foamable vinyl-aromatic polymer particles contain a blowing agent and are treated to speed up the formation of pores during the first stage of foaming. 0.01-0.5 pref. 0.02-0.1 wt. % (w.r.t. the polymer + blowing agent) of esters, obtained by reaction of fatty acid(s) with hydroxy-alkane sulphonates contg. 2-8C is applied to the surface of the particles. Pref. the fatty acid(s) used are 8-18C satd. and the hydroxy alkane sulphonate is pref. hydroxyethanesulphonate.</p> |