METHOD OF PREPARING THERMOPLASTIC PARTICLES OF VINYLIDENE CHLORIDE/VINYL CHLORIDE COPOLYMERS Russian patent published in 2006 - IPC C08F14/00 C08F14/06 C08F14/08 C08F214/00 C08F214/06 C08F214/08 

FIELD: polymer production.

SUBSTANCE: invention relates to the field of production of thermoplastic polymer materials, in particular vinylidene chloride/vinyl chloride copolymers, suitable for manufacturing technical-destination articles. Method is accomplished by copolymerization of vinylidene chloride and vinyl chloride monomers in aqueous dispersion and in presence of dispersing agent, copolymerization initiator, and subsequently added polymerization stopper, after which unreacted monomers are removed and copolymer particles are recovered from aqueous suspension and dried. Method is characterized by that copolymerization of vinylidene chloride and vinyl chloride monomers proceeds in presence of plasticizing and thermally stabilizing composition including epoxydized derivatives of carboxylic acid triglycerides and carboxylic acid esters in amounts below or equal to 12% based on the total mass of monomers being copolymerized at weight ratio of above composition to carboxylic acid esters 1:(0.75-6). In this case, the composition can be introduced either in one time in the beginning of the copolymerization process or stepwise: time in the beginning of the copolymerization process but after removal of when unreacted monomers using known procedures. Accordingly, implementation of the invention allows preparation of copolymer particles with improved thermoplastic properties appropriate for manufacturing technical-destination articles through known processes without additional treatment of polymer particles and at temperature by 5-10°C lower. Moreover, the whole technological cycle is simplified owing to exclusion of stages wherein plasticizer should be added to dried copolymer and compound formed therefrom before formation of film. Film materials manufactured from above-described copolymer particles are clear, defectless, and produce no smell.

EFFECT: enhanced copolymerization efficiency.

6 cl, 1 tbl, 5 ex