Abstract: A process for making high-purity foam moldings without the use of organic blowing agents involves the use of inorganic gases such as carbon dioxide, nitrogen, air and other pneumatogens.The process involves the simultaneous impregnation and purification of the polymers with or without foaming. If foaming is not done in the extractor, the polymeric particles can be foamed in pre-expanders or expanded and molded in downstream equipment.

Abstract: The process of making foam moldings without the use of organic blowing agents involves the use of inorganic gases such as carbon dioxide, nitrogen, air, solid carbon dioxide and other pneumatogens. Because of the rapidity with which these gases diffuse out of the polymer particles, it is necessary to pre-expand the particles and then reimpregnate the particles with the same or different gas.

Abstract: In the suspension polymerization of styrene monomers in water using suitable suspension stabilizers, the only modifier needed has been found to be organotin compounds in amounts from 10 to 1000 ppm based on monomer. The product beads have a narrow bead size distribution.

Abstract: Thermoplastic particles are suspended in water or other suspending fluids with a suspending aid(s) to prevent agglomeration of the beads, pellets or particles. To this suspension is added monomer(s) containing a multifunctional initiator(s). The monomer and initiator(s) are preemulsified in water or other fluid(s) before the addition in order to improve distribution of the monomer(s) and initiator(s) in or on the particles. After or during the addition(s), the suspension temperature is raised to cause polymerization. The procedures may be repeated to increase the coating or penetrated polymer content. New compositions of matter are made by this technique wherein the new compositions are plastic resins either coated or penetrated, or both, with a thermoplastic(s) of very high molecular weight not obtainable by present, commercial polymerization techniques. The compositions are superior to the feed resins because of the enhancement of physical properties brought about by the high molecular weights phase(s).

Abstract: Thermoplastic particles are suspended in water or other suspending fluids with a suspending aid(s) to prevent agglomeration of the beads, pellets or particles. To this suspension is added monomer(s) containing a multifunctional initiator(s). The monomer and initiator(s) are pre-emulsified in water or other fluid(s) before the addition in order to improve distribution of the monomer(s) and initiator(s) in or on the particles. After or during the addition(s), the suspension temperature is raised to cause polymerization. The procedures may be repeated to increase the coating or penetrated polymer content. New compositions of matter are made by this technique wherein the new compositions are plastic resins either coated or penetrated, or both, with a thermoplastic(s) of very high molecular weight not obtainable by present, commercial polymerization techniques. The compositions are superior to the feed resins because of the enhancement of physical properties brought about by the high molecular weights phase(s).