METHOD OF SELF-EXTINGUISHING FROTHED PLATE MAKING Russian patent published in 2002 - IPC

FIELD: building materials, chemical technology. SUBSTANCE: invention relates to a method of making self-extinguishing frothed plates from polystyrene by extrusion method. Self-extinguishing frothed plates are made by mixing polystyrene with hexabromocyclododecane as an antipyrine agent and a mixture of tri-(2,4-di-tert.-butyl)-phosphite with octadecyl-3-(3,5-di-tert. -butyl-4-hydroxyphenyl)-propionate as a synergistic addition taken in the ratio = 4: 1 and in the amount 0.005-0.1% of mass to be extruded. Then a mixture is melted into an extruder device, pore-forming agent is added to a melt and a mixture is subjected for extrusion in the presence of a nuclezating agent in the presence of talc through a flat-slotting draw plate and frothed plates are formed. A mixture of talc with particles dispersity 3-10 mcm taken in the amount 0.2-1.5 wt.% and aluminium hydroxide taken in the amount 0.01-0.06 wt. % of mass of mixture to be extruded. Method provides making frothed plates with high strength indices and inflammability of class G1. Invention can be used in municipal and industrial building as a heat-insulating material with decreased inflammability. EFFECT: improved method of making, valuable properties. 3 cl, 1 tbl, 14 ex