Chlorinated poly , flame resistance

Poly(vinyl chloride). PVC is a hard, brittle polymer that is self-extinguishing. In order to make PVC useful and more pHable, plasticizers (qv) are added. More often than not the plasticizers are flammable and make the formulation less flame resistant. Flammability increases as the plasticizer is increased and the relative amount of chlorine decreased, as shown in Table 7. The flame resistance of the poly(vinyl chloride) can be increased by the addition of an inorganic flame-retardant synergist. 

Polyolefines, like simple alkanes, can be chlorinated by chlorine giving hydrogen chloride and chlorinated products such as Tyrin, used as plasticizers and flame retardants, and poly (vinyl dichloride), which has better heat resistance than PVC and is used for hot water piping. 

Poly (3,3-Bis(Chloromethyl)Oxetane) This is marketed by Hercules as Penton chlorinated polyether. Its thermal, flame, and chemical resistance are used primarily for corrosion-resistant equipment in the process industries, such as valves, fittings, pumps, meters, and linings for steel pipe and tanks, for service in many corrosive atmospheres up to 250°F. or higher. At 4.50/pound, growth possibilities appear limited by increasing competition from lower-cost materials. 

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