FIELD: chemistry of polymers.
SUBSTANCE: invention relates to composition of foaming styrene polymer as beads, to method for its preparing and to materials - foamed beads and shaped articles made of polystyrene foam. The homogenous composition of polymer as beads comprises, mas. p. p.: (a) 100 - styrene (co)polymer with average-weight molecular mass 150 000-300 000 Da and the content of residual styrene monomer less 2 000 ppm; (b) 2-9 - at least one gaseous agent comprising n-pentane; (c) from 0.1 to 1.0 - petroleum wax representing mixture of (C18-C80)-alkanes; and (d) 0-1 - nucleating agent taken among synthetic wax of Fischer-Trosch or polyolefin waxes. Prepared composition is mixed in simultaneous heating with steam for one or some runs through vessel fitted with a mixer. Articles are shaped from foamed beads of the composition. Invention provides increasing rate of foaming beads, enhanced output at stage of producing foaming being without significant effect on the final stage of shaping.
EFFECT: improved preparing method.
20 cl, 4 tbl, 6 ex
