公开(公告)号：DE3682459D1

公开(公告)日：1991-12-19

申请号：DE3682459

申请日：1986-08-12

Applicant: BASF AG

Inventor： GOETTSCH MANFRED DR ,  KINDLER HUBERT DR ,  MOEDERSHEIM NORBERT ,  RUDOLPH GUENTHER RUDOLPH GUENT

IPC: C08J3/20 ,  C08K5/02 ,  C08L25/06

Abstract: Fire retardant polystyrene compsns. contg. (a) halogenated hydrocarbon flame retardant agents together with at least one of (b) a synergist for the (a), (c) stabilisers, (d) antioxidants and (e) additives, are made by a multistage mixing process comprising (1) premixing polystyrene with the (a) and part or all of the (c) at temps. up to 100 deg.C, (2) continuously feeding the premix into a continuously operating single or twin screw extruder or kneader, opt. together with further additives, (3) in a subsequent mixing zone of the extruder, feeding into the prod. stream a monomer- and solvent-free melt of a polystyrene resin at 200-250 deg.C, opt. together with other additives, and (4) extruding and granulating the resulting flame resistant polystyrene compsn..