Expandable polystyrene with stabilized cell structure

Abstract From the Canadian patent

Incorporating 500 to 5,000 preferably 2,000, to 4,000 parts per million of Fischer-Tropsch wax of high congealing point into beads of expandable polystyrene made by suspension polymerization yields greater advantages and, conditions (time, temperatures, and recipe) of the polymerization become less critical. The drying or conditioning ster before the pre-expansion under particular conditions to generate a suitable cell structure need not be followed and a step of coating with zinc stearate or the like before the pre-expansion may be omitted. Unexpanded beads are obtained which yield consistent cell structure independent, of conditions of their storage. Beads of higher pentane content can be …