Abstract: The present invention is an improved process for producing high molecular weight monovinylidene aromatic polymers and polymodal compositions by free radical polymerization of a vinyl aromatic monomer in the presence of a vinyl acid, wherein the improvement comprises neutralizing the acid after production of the desired amount of high molecular weight monovinylidene aromatic polymer by adding a base.

Abstract: The invention includes a process comprising steps of (1) forming a admixture of (a) a vinyl aromatic polymer and (b) a coupling amount of at least one poly(sulfonyl azide); (2) introducing the vinyl aromatic polymer or admixture into a melt processing device; (3) melting the vinyl aromatic polymer or admixture, and thereafter (4) exposing the admixture to a temperature, hereinafter, melt process temperature, sufficient to result in coupling of the vinyl aromatic polymer. The invention also includes a process of increasing the molecular weight of a vinyl aromatic polymer by heating an admixture of at least one vinyl aromatic polymer and a coupling amount of at least one poly(sulfonyl azide).

Abstract: The present invention is a process for producing a high molecular weight monovinylidene aromatic polymer, comprising free radically polymerizing a vinyl aromatic monomer in the presence of less than 10 ppm of a vinyl acid having a pKa at 25.degree. C. of less than 2.0.

Abstract: The invention includes a process comprising steps of (1) forming a admixture of (a) a vinyl aromatic polymer and (b) a coupling amount of at least one poly(sulfonyl azide); (2) introducing the vinyl aromatic polymer or admixture into a melt processing device; (3) melting the vinyl aromatic polymer or admixture, and thereafter (4) exposing the admixture to a temperature, hereinafter, melt process temperature, sufficient to result in coupling of the vinyl aromatic polymer. The invention also includes a process of increasing the molecular weight of a vinyl aromatic polymer by heating an admixture of at least one vinyl aromatic polymer and a coupling amount of at least one poly(sulfonyl azide).

Abstract: A polystyrene is prepared from a C.sub.8 cracker stream by first hydrogenating phenylacetylene to styrene and subsequently anionically polymerizing the styrene.

Abstract: A process for preparation of water-soluble polyvinylbenzyl quaternary ammonium halides by the halomethylation and subsequent quaternization of a polystyrene with the improvement that said polystyrene is a cationically-initiated polystyrene of about 1000 to about 50,000 M.sub.w and M.sub.w /M.sub.n ratio of less than about 8, preferably having less than about 0.1 mole percent residual unsaturation. The quaternized product is useful as a water clarifier and as electroconductive film for copying paper and the like.