Polyvinyl dichloride plastic

The direct addition of chlorine to ethylene produces ethylene dichloride (1,2-dichloroethane). Ethylene dichloride is the main precursor for vinyl chloride, which is an important monomer for polyvinyl chloride plastics and resins. 

Vinyl resins (1934) n. According to common chemical nomenclature, all resins and polymers made from monomers containing the vinyl group, H2C=CHX. In the chemical literature, polystyrene, polyolefins, polymethyl methacrylate and many other styrenic, ethenic, and acrylic co-polymers are classified as vinyls. In the plastics literature, the above materials are given their own classifications and the term vinyl is restricted to compounds in which X, above, is not H, a hydrocarbon radical, nor an acrylic-type ester. In daily use, the term vinyl plastics refers primarily to polyvinyl chloride and its co-polymers, and secondarily to the following polyvinyl acetal, polyvinyl acetate, poly-vinyl alcohol, polyvinyl but-yral, poly(n-vinylcar-bazole), polyvinyl dichloride, polyvinyl formal, polyvinylidene chloride, polyisobutylvinyl ether, and poly (1-vinylpyrrolidone). Mishra MKM, Yagd Y (1998) Handbook of vinyl polymerization. Marcel Dekker, New York. 

Saran (Dow polyvinylidene dichloride) is a tough, chemically resistant plastic available in a variety of forms that are useful in the laboratory. Saran pipe or tubing can easily be welded to itself or sealed to glass and is useful for handling corrosive solutions. Thin Saran film, available commercially as a packaging material, is useful for windows, support films, etc. Mylar (du Pont polyethylene terephthalate) film and other polyester films are also useful for these purposes. Mylar is chemically inert and has excellent electrical properties for electrical insulation and for use as a dielectric medium in capacitors. Much thinner than these are films that can be made in the laboratory by allowing a dilute ethylene dichloride solution of Formvar (polyvinyl acetal) to spread on a water surface and dry. 

Since most materials are opaque to the electron beam, even when only a few hundred nanometers thick, special problems arise in the production of suitable mounted specimens. Specimen support films are usually made of plastic or carbon, though other materials have also been used. Suitable film solutions may be made up of 2% w/v formvar (polyvinyl formal) in ethylene dichloride or chloroform. 

Oxychlorination of hydrocarbons refers to a chemical reaction in which oxygen and hydrogen chloride react with a hydrocarbon in the vapor phase over a supported copper chloride catalyst to produce a chlorinated hydrocarbon and water. The oxychlorination of ethylene to produce 1, 2-dichloroethane (commonly, ethylene dichloride (EDC)) is of the greatest commercial importance. EDC is the precurser for vinyl chloride monomer, which when polymerized to polyvinyl chloride (PVC), becomes one of the most conunonly used commercial plastics. The overall oxychlorination reaction of ethane is given by... 

Plastic, carbon and metal films (Section 4.7) are used as specimen supports on TEM grids. There are two plastic support materials in use collodion, 0.5% solution of nitrocellulose in amyl acetate and formvar, 0.25% polyvinyl formal in ethylene dichloride. These polymers are available as powders, solutions or prepared films on TEM grids. Formvar films, especially holey ones, are used as substrates for the formation of holey carbon films. Today, collodion is not used too often, as it is not as stable in the electron beam as formvar or carbon films. 

About 96% of all ethylene dichloride produced is used to make vinyl chloride monomer for polymerization into polyvinyl chloride resins (PVC). A very small amount of PVC is used with NBR by the rubber industry. However, most of the PVC output is used by the plastics industry, mainly for commercial and residential construction. 

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