Vinylidene dichloride copolymers

Halogen-containing fibers namely modacrylics fibers are typically copolymers of vinyl chloride or vinylidene dichloride and acrylonitrile. Although these fibers do not melt-flow or drip, they shrink rapidly when exposed to the fire. Because of this, the best use of modacrylic fibers is in blends. 

Vinylidene chloride/vinyl chloride polymer. See Vinylidene chloride/vinyl chloride copolymer Vinyl chloride/vinylidene chloride copolymer Vinylidene dichloride. See Vinylidene chloride... 

Copolymers of vinyl chloride are used both as solid resins, for example, in solvent adhesives (vinyl chloride-vinyl acetate copolymers), and as additives in plastisol adhesives, but especially as synthetic resin emulsions for heat-sealing adhesives. Important copolymers are those of vinyl chloride with vinyl acetate, acrylates, or maleates, as well as copolymers of vinylidene dichloride with acrylates or acrylonitrile. 

The content of acrylonitrile units in modacrylic fibres is, by definition, between 35 and 85 wt%. These fibres usually have a high concentration of halogen-containing comonomers (such as vinylidene dichloride, vinyl bromide and vinyl chloride) which improve their flame resistance. Related to modacrylic fibres, but with a higher content of halogen-containing monomers, are chlorofibres, produced only in small quantities from poly(vinyl chloride), poly(vinylidene dichloride) and from their copolymers, e.g. with vinyl acetate. ... 

Although 1,1-dichloroethylene (vinylidene chloride) is a relatively small-volume product, it provides a way of upgrading the unwanted 1,1,2-trichloroethane by-product from the manufacture of ethylene dichloride and 1,1,1-trichloroethane. Its major use is as an intermediate for polyvinylidene chloride and its copolymers, which are important barrier materials for food packaging. The remainder goes to the manufacture of 1,1,1-trichloroethane. 

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