JPH0427267B

1. A thermoplastic moulding material essentially containing (A) polystyrene, and (B) at least one non-elastomeric, radially branched block copolymer which consists of 60 to 95% by weight of a monovinylaromatic monomer and 40 to 5% by weight of a conjugated diene, and has at least two types of copolymer blocks forming the branches and having, on average, a different structure, at least 50% by weight of the total copolymerized monovinylaromatic monomer units of the radially branched block copolymer being contained in the form of a block as terminal polymer segment in one ore more of the copolymer blocks forming the branches, characterized in that the moulding material additionally contains, as component (C), a lubicant in an amount of from 0,1 to 5% by weight, based on (A) + (B) + (C), and that there is used as component (A) a polystyrene having a viscosity number of from 65 to 78 ccm/g and a ratio of the weight average molecular weight to the number average molecular weight Mw /Mn of 1.5 to 4, component (A) being present in an amount of from 2 to 45% by weight, based on (A) + (B) + (C).