PRODUCTION OF FLAME RETARDANT HIGHLY EXPANDABLE POLYSTYRENE

PURPOSE: A process of preparing the title resin having a foaming agent content of 3 to 4% such as pentane and butadiene regulated by VOCs (volatile organic materials) and restricted in its using amount, imposing almost no restrictions on product suitability and having excellent heat stability is provided, which produces highly-expandable styrene resin capable of being used for an interior material for building or packing material. CONSTITUTION: The highly-expandable styrene resin is prepared by a process consisting of: dispersing 0.5 to 1.0 parts by weight of glyceryl tristearate, 0.05 to 0.5 parts by weight of an ethylenevinylacetate-alcohol copolymer, 0.1 to 1.0 parts by weight of hexabromocyclododecane, 0.05 to 0.5 parts by of dicumylperoxide in 100 parts by weight of a styrene based monomer selected from the group consisting of styrene, acrylonitrile, α-methylstyrene and mixtures thereof; adding less than 4.0% by weight of a volatile organic compound of formula: CnH2n+2 when the polymerization rate attains 30 to 50% ; and adding 0.01 to 0.1 parts by weight of zinc stearate after manufacturing expandable styrene resin particles.