TRANSPARENT MOLDING COMPOUND

A moulding composition comprising, based on the sum of A, B, C and D, A: from 5 to 50% by weight of a methyl methacrylate polymer A comprising, based on A, A1: from 80 to 100% by weight of units of methyl methacrylate (A1) and A2: up to 20% by weight of units of an alkyl acrylate having up to 8 carbon atoms in the alkyl radical (A2), B: from 5 to 50% by weight of a styrene-acrylonitrile polymer B comprising, based on B, B1: from 75 to 85% by weight of styrene and B2: from 15 to 25% by weight of acrylonitrile, C: from 0.02 to 3.0% by weight of a polysiloxane of the formula I in which R is C1-C6-alkyl or aryl, R is alkyl, aryl or alkoxy and n is at least 5, and the polysiloxane has a viscosity at 25 DEG C of less than 500 cSt, and D: from 5 to 60% by weight of a graft copolymer D having a particle size of 0.2 mu m or less, comprising, based on D, D1: from 30 to 80% by weight of an elastomeric graft base D1 predominantly comprising units of butadiene, isoprene or a C4-C8-alkyl acrylate having a glass transition temperature of below 0 DEG C, D2: from 20 to 70% by weight of a graft shell D2 comprising, based on D2, D21: from 30 to 100% of units of one or more (meth)acrylic esters (meth)acrylates of C1-C8-alkanols and D22: up to 70% by weight of units of a vinylaromatic monomer, with the proviso that the difference between the refractive index n D of the graft copolymer D and that of the mixture or A, B and C is less than 0.01.