Thermoplastic molding compositions with improved optical properties

A thermoplastic molding composition comprising a mixture of

• (a) from 10 to 50% by weight, based on the entirety of components (A), (B), and (C), of a methyl methacrylate polymer as component (A), obtainable via polymerization of a mixture composed of
• (a1) from 90 to 100% by weight, based on (A), methyl methacrylate as component (A1), and
• (a2) from 0 to 10% by weight, based on (A), of a C1-C8-alkyl ester of acrylic acid as component (A2), and
• (b) from 20 to 60% by weight, based on the entirety of components (A), (B), and (C), of a copolymer as component (B), obtainable via polymerization of a mixture composed of
• (b1) from 70 to 90% by weight, based on (B), of a vinylaromatic monomer as component (B1), and
• (b2) from 10 to 30% by weight, based on (B) of a vinyl cyanide as component (B2), and
• (c) from 20 to 70% by weight, based on the entirety of components (A), (B), and (C), of a graft copolymer as component (C), obtainable from
• (c1) from 50 to 70% by weight, based on (C), of a core as component (C1), obtainable via polymerization of a monomer mixture composed of
• (c11) from 65 to 89.9% by weight, based on (C1) of a 1,3-diene as component (C11), and
• (c12) from 10 to 34.9% by weight, based on (C1), of a vinylaromatic monomer as component (C12), and
• (c13) from 0.1 to 5% by weight, based on (C1), of an agglomeration polymer as component (C13), and
• (c2) from 15 to 25% by weight, based on (C), of a first graft shell as component (C2), obtainable via polymerization of a monomer mixture composed of
• (c21) from 30 to 49.9% by weight, based on (C2), of a vinylaromatic monomer as component (C21), and
• (c22) from 50 to 69.9% by weight, based on (C2), of a C1-C8-alkyl ester of methacrylic acid and/or of a C1-C8-alkyl ester of acrylic acid as component (C22), and
• (c23) from 0.1 to 3% by weight, based on (C2), of a crosslinking monomer as component (C23), and
• (c3) from 15 to 25% by weight, based on (C), of a second graft shell as component (C3), obtainable via polymerization of a monomer mixture composed of
• (c31) from 20 to 80% by weight, based on (C3), of a C1-C8-alkyl ester of methacrylic acid as component (C31) and
• (c32) from 20 to 80% by weight, based on (C3), of a further monomer as component (C32), and
• (d) optionally, amounts of up to 20% by weight, based on the entirety of components (A), (B), and (C), of additives as component (D),
• wherein
• component (C32) is a vinylaromatic monomer and
• the graft copolymer (C) is produced via emulsion polymerization and is isolated from the reaction mixture by precipitation resulting from shear.