Abstract: Vinyl halide homopolymers, particularly polyvinyl chloride, which exhibit improved processing characteristics without sacrificing physical properties are prepared by partially polymerizing a vinyl halide monomer at an initial temperature level whereupon the reaction temperature is then raised and the polymerization is continued at this increased temperature level preferably while in the presence of a chain transfer agent so as to obtain a polymer having an average molecular weight range different from that obtainable at the first reaction temperature. The resulting polyvinyl chloride provides the physical characteristics of polymer blends but can be processed much more readily than a mechanical blend of homopolymers of varying molecular weights, fusing more easily and without the undesirable formation of fish eyes.

Abstract: Vinyl halide polymers, preferably polyvinyl chloride, which exhibit improved processing characteristics without sacrificing physical properties are prepared by partially polymerizing vinyl halide monomer at a first reaction temperature and then changing the reaction temperature and continuing the polymerization at a second temperature conducive to forming a polymer of an average molecular weight range different from that obtainable at the first reaction temperature. The product provides the physical characteristics of polymer blends but can be processed without formation of fish eyes.

Abstract: Aqueous suspensions of discrete particles of polymer, for instance polyvinyl latices, are heated with solvents which are at least partially water-miscible, particularly certain shortchain ketones, until the polymer is agglomerated to the desired degree. Various water-soluble inorganic metal salts, especially alkali metal and alkaline earth metal halides and sulfates, may also be added to facilitate the agglomeration. Novel macromolecular resins of high absorptivity are thus produced, comprising the fine particles of polymer cofused in a reticulated structure, the degree of cofusion being controlled at will by the process conditions selected.