METHOD FOR PRODUCTION OF FOAMED PLATES WITH HIGH COMPRESSIVE STRENGTH Russian patent published in 2001 - IPC

FIELD: production of foamed plates from polystyrene by extrusion method. SUBSTANCE: method consists in production of plates having a compressive strength of at least 0.50 MPa. method comprises mixing of polystyrene with physical nuclesator-talk, melting of the mixture in extruder, introduction of blowing agent in the melt and extrusion through a plano-slotted die with formation of a foam plate. The used talk has a dispersity of 3 to 10 μm and is introduced in the amount of 2.0 to 3.4% of the mixture mass. In addition, mixture of inorganic compound of aluminium, such as sulfate or hydroxide of aluminium, are introduced in the mixture (0.06 to 0.08 mas.%). Polystyrene with a melt flow index of 2.6 to 7 g/10 min is taken as polystyrene. EFFECT: enhanced efficiency. 4 cl, 1 tbl, 9 ex