polymerkomposition containing linear alternating copolymers of polydiensegment and polyvinylaromatiska segments and process for the production thereof

摘要

1. CASE 2967 "POLYMERIC COMPOSITIONS AND METHOD FOR PREPARING THEM" New polymeric compositions comprising: (a) a linear copolymer constituted by four alternating blocks, which can be represented by the formula (I) or (II) B1-T-A1-B2-A2 (I) or B1 A1-B2-T-A2 (II) wherein: B1 and B2 are polydienic blocks, preferably polybutadienic blocks; A1 and A2 are polyvinylaromatic blocks and preferably polystyrenic blocks; T is a portion of random copolymer formed by dienic and vinylaromatic monomer units; (b) a linear copolymer constituted by two blocks, which can be represented by the formulae (III) or (IV) B3-T-A3 (III) or B3-A3 (IV) wherein: B3 is a polydienic block; A3 is a polyvinylaromatic block; 2. and T has the above seen meaning. The polymeric composition, which can be blended with polystyrene, can be obtained both by blending the individual components, and by means of novel and original synthesis processes which make it possible both (A) and (B) components to be obtained simultaneously. The polymeric compositions according to the instant invention are suitable for all of those uses in which characteristics of impact strength, transparence and processability are required.