Vinyl chloride-acrylonitrile

Membrane stmcture is a function of the materials used (polymer composition, molecular weight distribution, solvent system, etc) and the mode of preparation (solution viscosity, evaporation time, humidity, etc). Commonly used polymers include cellulose acetates, polyamides, polysulfones, dynels (vinyl chloride-acrylonitrile copolymers) and poly(vinyhdene fluoride). 

Vinyhdene chloride copolymers are available as resins for extmsion, latices for coating, and resins for solvent coating. Comonomer levels range from 5 to 20 wt %. Common comonomers are vinyl chloride, acrylonitrile, and alkyl acrylates. The permeability of the polymer is a function of type and amount of comonomer. As the comonomer fraction of these semicrystalline copolymers is increased, the melting temperature decreases and the permeability increases. The permeability of vinylidene chloride homopolymer has not been measured. 

Polymerization Exothermic reaction which, unless carefully controlled, can run-away and create a thermal explosion or vessel overpressurization Refer to Table 7.20 for common monomers Certain processes require polymerization of feedstock at high pressure, with associated hazards Many vinyl monomers (e.g. vinyl chloride, acrylonitrile) pose a chronic toxicity hazard Refer to Table 7.19 for basic precautions... 

Many vinyl monomers (e.g. vinyl chloride, acrylonitrile) pose a chronic toxicity hazard... 

Dynel Vinyl chloride-acrylonitrile copolymers Union Carbide... 

Poly(vinylidene chloride) (XLII) and its copolymers with vinyl chloride, acrylonitrile, and acrylates, usually produced by the suspension or emulsion process, are useful as oil, fat, oxygen, and moisture-resistant packaging films (Saran wrap), containers, coatings, tank liners, and monofilaments in drapery fabrics and industrial filter cloths. 

Poly(methyl methacrylate) Vinyl chloride Acrylonitrile Ethylene Acrylic add Methylacrylate Acrylonitrile Styrene Butylene dimethacrylate Acrylic add... 

Thus far this scheme has been incorporated into OSHA standards for 5 contaminants, i.e., vinyl chloride, acrylonitrile, benzene, lead, and arsenic, and has become a legal requirement of all employers whose personnel may be exposed to these substances. This scheme is likely to be incorporated into virtually all future OSHA standards (15). 

Vinylidene chloride is used principally in copolymers with vinyl chloride, acrylonitrile and other monomers for packaging materials, adhesives and synthetic fibres (Lewis, 1993). 

Kamakatsu, T, E. Fukada, and K. Shinohara Electrical conduction of heated poly(vinyl chloride)acrylonitrile copolymer. Rep. Prog. Pol. Phys., Japan 4, 317 (1964). 

Unsaturated vinyl esters for use in polymerization reactions are made by the esterification of olefins. The most important ones are vinyl esters vinyl acetate, vinyl chloride, acrylonitrile, and vinyl fluoride. The addition reaction may be carried out in either the liquid, vapor, or mixed phases, depending on the properties of the acid. Care must be taken to reduce the polymerization of the vinyl ester produced. 

Radial temperature profiles were almost constant as experimentally observed and later predicted by the model. This indicates that the thermal conductivity for the styrene/water systems studied is sufficiently high to quickly heat the liquid as it enters the tube, and efficiently remove the heat released by the reaction. In Figure 6 it is seen that as G2 increases, a high ratio of heat released by reaction to heat removed by convection causes a temperature overshoot. Such an overshoot was not observed for styrene, either experimentally or with the model. Figure 7 presents predicted axial temperature profiles for several monomers at standard conditions, with constants as in Table III. While equations (4) and (5) require the monomer to be only partially soluble, the results shown in Figure 7 indicate a strong exotherm for vinyl chloride, acrylonitrile and vinyl acetate. 

Chapen, E. C., G. E. Ham, and R. G. Fordyce Copolymerisation. IV. The validity of the tripolymer equation for the system Styrene-vinyl chloride-methyl acrylate and styrene-vinyl chloride-acrylonitrile. J. Am. Chem. Soc. 70, 538 (1948). 

The high pressure polymerization of ethylene can be slightly modified for the copolymerization of ethylene with vinyl- and acrylic-type monomers such as vinyl acetate, vinyl chloride, acrylonitrile, or acrylic esters. Some of these copolymers of ethylene and vinyl acetate or maleic anhydride are already available and have found various applications in plastics, coatings, and adhesives. Copolymers of ethylene and vinyl chloride and of ethylene and acrylonitrile appear particularly interesting because of the low cost of monomers and the properties of the copolymers. Although their synthesis has been disclosed in a number of patents their larger scale production is still in a state of development. 

Interesting polymers for vesicular photography are homopolymers and/or co-polymers of vinylidene chloride, vinyl chloride, acrylonitrile, styrene, acrylates or methacrylates, epoxies and polyvinylformal or -butyral. The base polymer is generally polyethylene terephthalate. 

On account of its low thermal stability, polyfvinylidene chloride) is seldom used in paints. Vinylidene chloride copolymers with vinyl chloride, acrylonitrile, or acrylates are mainly employed. These heat-sealable copolymers are efficient gas barriers and have an outstanding resistance to chemicals. They are marketed as solid resins and dispersions. Vinylidene chloride copolymers are mainly used for coating foodpackaging foils. They are also important in paint coatings where good chemical resistance is required. 

Dynel Vinyl chloride/acrylonitrile copolymer Union Carbide, U.S. 

Vinyl chloride Acrylonitrile-c )- -butyl acrylate n had 53, 67 or 84 mol% butyl aciylate Piglowski and Kammer (1990)... 

Dynel n. Vinyl chloride/acrylonitrile copolymer. Manufactured by Union Carbide, USA. 

Vinyl monomers such as CH2=CH2 (and others such as CF2=CF2), mono substituted ethylenes CH2=CH(R) (such as propylene, styrene, vinyl chloride, acrylonitrile, methyl methacrylate, etc.), some disubstituted olefins CH2=CRR (such as isobutylene), dienes (such as 1,3-butadiene, isoprene) and also monomers such as acetylene can be polymerized by various polymerization methods to afford linear chain polymers. In all of these po-... 

Zhang and Prud homme estimated values of the binary interaction parameters for PCL with vinylidene chloride copolymers known as Saran, that is with copolymers of vinylidene chloride with, separately, vinyl chloride, acrylonitrile or vinyl acetate [74]. Interaction parameters were estimated from melting point depressions. Values obtained were found to be composition-dependent and are... 

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