Abstract: Foamed polymeric materials exhibiting improved heat resistant properties and improved mechanical properties, as compared with known foamed styrene polymer materials, are obtained by expanding a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart enhanced heat resistant properties to the blend.

Abstract: Foamed polymeric materials exhibiting improved heat resistant properties and improved mechanical properties, as compared with known foamed styrene polymer materials, are obtained by expanding a polymer blend including a syndiotactic styrene polymer and an amount of an amorphous polymeric material which will impart enhanced heat resistant properties to the blend.

Abstract: An improved process for forming hydroperoxide derivatives of rubbery polymers. The hydroperoxide derivatives being particularly well suited for use as intermediates in forming graft rubbery polymers. The process involves dissolving a rubbery polymer in a monomer mixture and adding to the rubbery polymer/monomer mixture a photosensitizing agent. The rubbery polymer-monomer mixture is then oxygenated and exposed to light under conditions wherein triplet oxygen is converted to singlet oxygen. The improvement comprises adding to the rubbery polymer/monomer mixture a solvent capable of solubilizing the photosensitizing agent in the rubbery polymer/monomer mixutre. The solubilizer increases the yield of hydroperoxide derivatives of rubbery polymers formed by a factor of 3.

Abstract: Compounds which comprise an azo group linking an aliphatic group to an olefin-bearing aromatic group, for example t-butylazostyrene, can be polymerized at temperatures of 130.degree. C. or more without causing substantial thermal decomposition of the azo group. The compounds and their polymers may be stored indefinitely at ambient temperatures. The azo group in the polymer will decompose at temperatures in excess of 240.degree. C. to become a free radical initiator or cross-linking agent.

Abstract: A rubber-modified polymeric composition is disclosed. The rubber-modifying component comprises a grafted rubbery polymer, said grafted rubbery polymer being formed by a process, the steps of the process involving the formation of a hydroperoxidized rubbery polymer intermediate.

Abstract: Improved monovinyl aromatic monomer-acrylonitrile copolymers are prepared by polymerizing at temperatures above 80.degree. C in the presence of certain free radical initiators, the resultant polymers are prepared at high rates of conversion, have relatively high heat distortion temperatures, have a low oligomer content and generate relatively little additional acrylonitrile under fabrication conditions.