Vinyl chloride flammability limits

Methyl vinyl ether is rapidly hydrolysed by contact with dilute acids to form acetaldehyde, which is more reactive and has wider flammability limits than the ether [1], Presence of base is essential during storage or distillation of the ether to prevent rapid acid-catalysed homopolymerisation, which is not prevented by antioxidants. Even mildly acidic solids (calcium chloride or some ceramics) will initiate exothermic polymerisation [2],... 

Eggleston, Herrera, and Pish 1976 To provide needed data about the use of air entrained by a water spray to dilute flammable vapor releases below the lower flammability limit. Absorption/adsorption effects are insignificant in the case of ethylene and vinyl chloride. Sprinklers and water-spray nozzles vary widely in their efficiency as air movers. Flame quenching was not affected in any of the experiments Water sprays increased the rate of flame propagation. The air-pumping action of a water curtain can be used to set up a barrier to the horizontal flow of vapors. 

The flammable halocarbon gases and the vapors of the flammable liquids form explosive mixtures with air. The range of explosive limits is wide for vinyl chloride, methyl chloride, and ethyl chloride. 

Poly(vinyl acetate) dispersions form lightfast, dry, hard, brittle films. Plasticizers therefore have to be used (external plasticization), which are, however, volatile and lead to embrittlement of the films after a relatively short time. Internally plasticized dispersions of copolymers of vinyl acetate with vinyl laurate, butyl maleate, Versatic Acid esters, or ethylene form permanently flexible, nonaging films that are not, however, always sufficiently resistant to hydrolysis. Terpolymer (vinyl acetate-ethylene-vinyl chloride) dispersions form films that are more resistant to hydrolysis than homopolymer and copolymer dispersions. The films also have a higher mechanical strength and lower flammability. The glass transition temperature of the terpolymer can be varied within wide limits and properties can be matched to requirements by using a suitable choice of comonomers. The same is true of vinyl propionate copolymer dispersions. 

METHYL-l-PHENYL-ETHYLENE (98-83-9) C9H10 Flammable liquid. Forms explosive mixture with air [explosion limits in air (vol %) 0.9 to 6.1 flash point 129°F/54°C autoignition temp 1066°F/574°C Fire Rating 2], Easily polymerizable. Unless inhibited, forms unstable peroxides. Reacts with heat and/or lack of appropriate inhibitor concentration. Reacts with catalysts for vinyl or ionic polymerization, such as aluminum, iron chloride or 2,5-dimethyl-2,5-di(ieri-butylperoxy)hexane. Violent reaction with strong oxidizers, butyl lithium, oleum, xenon tetrafluoride. Incon atible with acids. The uninhibited monomer vapor may block vents and confined spaces by, forming a solid polymer material. Attacks aluminum and copper. On small fires, use dry chemical powder (such as Purple-K-Powder), foam, or CO2 extinguishers. 

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