Illustrative of such polymers are polystyrene, high impact polystyrene, a styrene-acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymers, polymethylmethacrylate, linear low-, low- and high-density polyethylene, vinyl chloride polymers and copolymers, propylene polymers and copolymers, polyesters and other engineering resins such as nylon.