Abstract: Reinforced polyoxymethylene materials containing(A) one or more polyoxymethylene homopolymers and/or copolymers and(B) wollastonite, advantageously in a weight ratio of components (A) to (B) of from 95:50 to5:50, with or without(C) additives in effective amounts, the wollastonite crystals (B) have a mean thickness equal to or smaller than 5 .mu.m and a mean length/thickness ratio equal to or greater than 5. The molding materials are prepared by introducing the wollastonite crystals (B) into the melt of component (A) at from 180.degree. to 260.degree. C., advantageously by means of an extruder.

Abstract: Impact-resistant polyoxymethylene molding materials containing(A) from 30 to 95% by weight of one or more polyoxymethylenes and(B) from 5 to 70% by weight of one or more elastomeric graft polymers which are prepared by emulsion polymerization, are dispersed in component A, have a mean particle diameter of from 0.08 to 2 .mu.m and are composed of1. from 60 to 90% by weight of a grafting base of crosslinked polybutadiene in which not more than 30% by weight of the butadiene may be replaced with isoprene, 2,3-dimethylbutadiene, styrene, p-methylstyrene, .alpha.-methylstyrene and/or (meth)acrylonitrile, and2. from 10 to 40% by weight of one or more grafted shells consisting of polymers of styrene and/or methyl methacrylate, in which not more than 15% by weight of the said monomers 2 may be replaced with acrylonitrile or a C.sub.1 -C.sub.8 -alkyl acrylate,the percentages A and B and the percentages 1 and 2 summing to 100, with or without(C) effective amounts of assistants,and a process for their preparation.

Abstract: Polyacetal molding materials which contain, as a stabilizer, from 0.1 to 10% by weight of a melamine resin, the latter being a melamine-formaldehyde condensate, having a mean degree of polymerization of from 1.2 to 6.0 and a melamine:formaldehyde ratio of from 1:2 to 1:5.5, which has been partially etherified with a C.sub.1 -C.sub.4 -alkanol so that the ratio melamine:ether radicals is from 1:1.5 to 1:5.0 and the ratio melamine:free methylol groups is from 1:0.5 to 1:3. The molding materials can be converted to moldings which can be used industrially at elevated ambient temperatures.