Production of fine particulate, expandable styrene polymers with improved properties

摘要

Process for the production of fine particulate, expandable styrene polymers by suspension-polymerizing styrene or possibly mixtures of styrene and other monomers having at least 50% by weight of styrene in the presence of expanding agents having low boiling points in incompletely filled reactors. The polymer beads to be charged with expanding agents are vigorously stirred during the addition of the expanding agent(s) in such a manner that these beads undergo the least possible contact in time and space with the gas phase and with each other, and so that the surface of the stirred medium retains a topology as free as possible from a funnel shape during stirring.