Abstract: Polymer dispersant of polycarboxylate type comprising at least one copolymer obtained from a monomer composition comprising, in moles: A) 40 to 95% of at least one unsaturated carboxylic monomer, B) 5 to 60% of at least one acrylic ester or methacrylic ester monomer comprising a polyether chain, C) 0 to 20% of at least one third monomer selected from: acrylic ester or methacrylic ester or acrylamide or acrylamide derivative or vinylaromatic monomer or its sulphonated derivative, the copolymer having a controlled molecular mass distribution and being able to be obtained by a process comprising the stages of: i) polymerization in aqueous solution at a temperature ranging from 70 to 95° C.

Abstract: The invention concerns transparent materials having good impact resistance, a high modulus and good heat resistance. The inventive materials comprise an amorphous matrix, preferably based on styrene/methyl methacrylate statistical copolymer whether impact-reinforced of not with a standard additive, and a block copolymer having at least an elastomeric block and at least a block partly or entirely compatible with the amorphous matrix.