Abstract: Latex foam molded articles are prepared using a plastic mold heated by means of microwave energy. The molded article can be readily released from the mold. The mold has good dimensional accuracy and a long serviceable lifetime. The walls of the mold are composed of a molding composition which has the following constituents:a) 20 to 100 parts by weight of polyphenylene ether,b) 0 to 30 parts by weight of styrene polymers,c) 0 to 30 parts by weight of impact-modifying additives,d) 0 to 40 parts by weight of reinforcing agents and/or fillers ande) 0 to 15 parts by weight of additives.The mold surface is passivated. Compared with conventional processes for the production of latex foam molded articles, the cycle time and the energy consumption are considerably reduced when this mold is used.

Abstract: A composite article is prepared by intimately bonding a latex foam with a thermoplastic molded part containing polyphenylene ether, the latex consisting of the following components, relative to its total rubber content:I. 20-100% by weight of SBR latex with a minimum proportion of more than 15% by weight of styrene in the solid polymer, andII. 80-0% by weight of natural-rubber latex or other, synthetic latexes.The combination is vulcanized to form a product which exhibits cohesive rupture within the foam body, when the foam body is subjected to separation.

Abstract: Aromatic hydroxydithiocarboxylic acid vulcanization accelerators for aqueous dispersions of unsaturated polymers are provided which eliminate the formation of health-threatening nitrosamines and do not adversely affect the vulcanization properties.

Abstract: A stryrene/butadiene graft copolymer latex has a graft substrate component with a comparatively high content of repeating units obtained by polymerization of styrene. The graft copolymer exhibits correspondingly comparatively hard and soft regions with a high and a low Tg, respectively.Vulcanizable compositions based thereon can be used for production of latex foams distinguished by a low compression set in a temperature range from 20.degree. to 70.degree. C., a high tensile strength, and a high elongation at break, and by a high compression resistance.

Abstract: A foamable, gelable and heat-vulcanizable composition for the manufacture of latex foam having, e.g., the following properties:(a) the indentation hardness must be sufficiently high;(b) the pore structure is to be uniformly fine for an adequate layer thickness,comprises a mixture of a rubber latex and a filler/rubber powder, a vulcanizing agent and conventional additives.The latex foams according to the invention are excellently suited as vibration damping materials, the mass to volume ratio and correspondingly the hardness being adjustable depending on the intended use to a high or low value.