Polyvinylchloride chlorinated

Chlorination of polyviitylchloride increases its tensile, compression and flexural strengths by about 30%. Impact strength more than doubles and even elongation doubles. Considering this, plasticization will most likely act in the opposite direction and reverse these ctonges important in some applications. In addition, plasticization lowers the heat distortion temperature that in many applications of chlorinated polyvinylchloride, CPVC, is a critical performance characteristic.  

In the cable industry, plasticization of CPVC by phthalates and phosphates improves the flexibility and processability of CPVC. However, the addition of plasticizer lowers the limiting oxygen index and increases smoke production. The schematic diagram below illnstrates the mechanism of degradation in the absence (A) and the presence (B) of the smoke-suppressing componnd - basic iron oxide, FeOOH.  

When exposed to heat CPVC produces substantial quantities of HCl, which is a volatile product of degradation. When FeOOH is not present (A), the phthalic add that is produced is then decaiboxylized to benzene. Under high temperature conditions benzene is further degraded and produces smoke. Only traces of phthalic anhydride are detected under these conditions. 

When a small amount of FeOOH (0.25 phr) is present, smoke production is suppressed by 40%. This is attributed to the formation of phthahc anhydride as shown by reactions in scheme (B). Only small quantities of FeOOH are needed because it is active in a cyclical process which keeps both required forms in equilibrium. Phthalic acid produces four times as much smoke as phthalic anhydride, which sublimes out of the system. 

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Several purely organic polymers like pyrolized polyacrylonitrile Sl polyamino-quinones 52>, vulcanized aniline black or ordinary aniline black 53>S4) and pyrolized chlorinated polyvinylchloride ss> were shown to be active for H2Oa decomposition. pH dependence was found in some cases, but mostly no correaltions were found with paramagnetism or semiconductivity. It has been shown S6> for the case of pyrolized polyacrylonitrile, that this polymer actually behaves as a polyquinone, capable of reversible electron transfer ... 

Chlorinated polyethylene Chlorinated polyvinylchloride Chloroprene, chlorinated rubber. Neoprene Chlorosulfonated polyethylene (or CSM)... 

With increasing amount of air mixed with the primary combustion products, the HF concentration decreases as is depicted for the three flare formulations in Figure 20.2. The investigation of HF formation on combustion of a payload similar to MTV-3 had been carried out in Ref [4]. The combustion had been carried out in a combustion chamber of 3.6 m volume lined with chlorinated polyvinylchloride (PVC). Fragments of either 12 and 25 g mass were burned and yielded between 1.41 and 3.88 mg HF per gram of MTV [4]. 

MAJOR POLYMER APPLICATIONS acrylics, chlorinated polyvinylchloride, ethylene methyl acrylate copolymer, methacrylate copolymer, polyester, polyetherimide, polyoxymethylene, polystyrene, polyurethane, proteins ... 

These data indicate that the polymethylmethacrylate (PMMA) surface was basic and that chlorinated polyvinylchloride (CPVC) and polyvinyl flouride (PVF) were both acidic and basic. Polypropylene was nonpolar, but corona treatment led to formation of acidic and basic sites. Another example of the effect of treatments on the surface of a plastic is shown in Table 6 (49). The surface activity of PVF was increased by plasma treatment, whereas corona treatment... 

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