Patent ID: 8648143

Claim:
A process for producing a thermoplastic molding composition, where the thermoplastic molding composition comprises a) as component A, from 3 to 79% by weight of one or more (methyl)styrene-acrylonitrile copolymers, which have no maleic-anhydride-derived units, b) as component B, from 15 to 91% by weight of one or more polyamides, c) as component C, from 5 to 50% by weight of one or more rubbers, d) as component D, from 1 to 25% by weight of one or more compatibilizers, e) as component E, from 0 to 2% by weight of one or more low-molecular-weight compounds, which comprise a dicarboxylic anhydride group, f) as component F, from 0 to 50% by weight of one or more fibrous or particulate fillers, and g) as component G, from 0 to 40% by weight of further additives, where each of the % by weight values is based on the total weight of components A to G, and these do not exceed 100% by weight, the process comprising mixing components A to G in a melt, by producing the melt comprising components A, B, and C in a first step of the process, in the absence of component D, and delaying the mixing to incorporate component D into the melt comprising components A, B, and C until a second step of the process; wherein the melt is produced in a screw extruder, which comprises, in a sequence along a direction of conveying, at least one feed zone, one plastifying zone, one homogenizing zone, and one discharge zone, after addition of components A, B, and C to the feed zone, in the first step of the process, in the absence of component D, and, in the second step of the process, after addition of component D to the homogenizing zone, the mixing to incorporate component D is carried out, and wherein the screw extruder has an effective length L, where the effective length L is defined as the distance from the first feed device for the addition of components A, B, and/or C to the discharge aperture in the direction of conveying, after addition of components A, B, and C, in the region from 0 L to 0.15 L, in the first step of the process, in the absence of component D, and, in the second step of the process, after addition of component D, in the region from 0.3 L to 0.99 L, the mixing to incorporate component D into the melt is carried out.