Hooker Chemicals & Plastics Corporation

Henry Kahn

Victor A Pattison

Anthony L Lemper

George C Hopkins

William L Schall

Jack L Nickels

David W Eastman

An improved bulk polymerization of vinyl halide is disclosed wherein reactor scale formation is substantially reduced by polymerizing in a single or two stage bulk process a vinyl halide monomer containing up to 50% of a comonomer in contact with a combination of a polyolefin, water, and an inert fine particle size additive which is a solid at the reaction temperature, or water and said additive, optionally in the presence of a surface active agent. Compositions produced by the process of the invention are useful in making films, coated fabrics and molded objects.

Process for the bulk polymerization of vinyl halide polymers showing

Polyvinyl chloride and polyvinyl chloride containing up to 20 percent of a comonomer can be obtained in the form of small particle size spherical glassy surface particles by a process of bulk polymerization of monomer or monomers comprising two stage polymerization wherein high shear agitation is used during the first stage and low shear agitation is used in the second stage. To obtain a reduction in particle size, the polymerization in the first stage is conducted in contact with at least one of (A) an additive comprising an organic or inorganic, inert, fine particle size material solid at least at reaction temperatures, and insoluble in said monomer or monomers used, and (B) a cationic, anionic, or non-ionic surface active agent. A portion of the polymerization in a second stage reaction is conducted at temperature and pressure sufficient to render the surface of the individual particles or agglomerates glassy and fused. The resulting polymers and copolymers produced have superior plastisol viscosity stability and fusion characteristics and excellent powder flow properties as compared to those of the prior art.

Composition of and method of obtaining small particle size polymers and

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Williamsville, NY, United States of America

Henry Kahn