It has now been found that molding materials based on (a) 20 to 90% by weight of elastomeric polymers, (b) 5 to 30% by weight of binder polymers, (c) 5 to 200% by weight, with reference to the binder polymer (b), of cement and/or slaked lime and (d) 0 to 50% by weight of mineral fillers have excellent properties when they contain as binder polymers (b) copolymers derived from 20 to 80% by weight of butadiene, 80 to 20% by weight of styrene and/0r acrylonitrile and/or 0 to.20% by weight of other olefinically unsaturated monomers in the form of an aqueous dispersion and in addition (e) 0.5 to 10% by weight of air-drying oils. The amount of binder polymers inthe molding materials is preferably from 10 to 20% by weight, with reference to the weight of the molding material.