HALOGEN FREE FIRE-RESISTANT FOAMING STYRENE POLYMERISATES Russian patent published in 2011 - IPC C08F12/08 C08J9/18 C08K3/00 

FIELD: chemistry.

SUBSTANCE: invention describes a method of producing halogen free fire-resistant foaming styrene polymerisates, involving the following steps: a) mixing molten styrene polymerisate using a static or dynamic mixer at temperature not lower than 150°C with (i) an organic blowing agent, (ii) 5-50 wt % (in terms of styrene polymerisate) filler selected from such powdered inorganic substances as talc, chalk, kaolin, aluminium hydroxide, aluminium nitrite, aluminium silicate, barium sulphate, calcium carbonate, titanium dioxide, calcium sulphate, silicic acid, quartz flour, aerosil, alumina or wollastonite; and (iii) 2-40 wt % (in terms of styrene polymerisate) expanded graphite with average particle size of 10-1000 mcm, (iv) red phosphorus, triphenylphosphate or 9,10-dihydro-9-oxa-10-phosphaphenanthrene -10-oxide; b) cooling the molten polymer containing the blowing agent and filler to temperature not lower than 120°C, c) passing through a plate with die holes, which are drilled holes with diametre at the outlet of the die holes not greater than 1.5 mm, and d) granulation of the molten mass containing the blowing agent directly after coming out of the plate with die holes under a layer of water at pressure between 1 and 20 bars.

EFFECT: obtaining cheap halogen-free fire-resistant styrene polymerisate.

1 cl, 1 tbl, 4 ex