Vinylidene chloride-acrylonitrile

By copolymerising the vinylidene chloride with about 10-15% of vinyl chloride, processable polymers may be obtained which are used in the manufacture of filaments and films. These copolymers have been marketed by the Dow Company since 1940 under the trade name Saran. Vinylidene chloride-acrylonitrile copolymers for use as coatings of low moisture permeability are also marketed (Saran, Viclan). Vinylidene chloride-vinyl chloride copolymers in which the vinylidene chloride is the minor component (2-20%) were mentioned in Chapter 12. 

In 1962 Courtaulds announced a flame-resisting fibre BHS said to be a 50 50 vinylidene chloride-acrylonitrile copolymer. This product has subsequently been renamed Teklan . 

Polymerizations conducted in nonaqueous media in which the polymer is insoluble also display the characteristics of emulsion polymerization. When either vinyl acetate or methyl methacrylate is polymerized in a poor solvent for the polymer, for example, the rate accelerates as the polymerization progresses. This acceleration, which has been called the gel effect,probably is associated with the precipitation of minute droplets of polymer highly swollen with monomer. These droplets may provide polymerization loci in which a single chain radical may be isolated from all others. A similar heterophase polymerization is observed even in the polymerization of the pure monomer in those cases in which the polymer is insoluble in its own monomer. Vinyl chloride, vinylidene chloride, acrylonitrile, and methacryloni-trile polymerize with precipitation of the polymer in a finely divided dispersion as rapidly as it is formed. The reaction rate increases as these polymer particles are generated. In the case of vinyl chloride ... 

For most of these esters, the free radical polymerization procedures are very similar to each other. With minor modifications, the considerations and preparations given here may be applied to many of the other common vinyl monomers such as styrene, vinyl acetate, vinylidene chloride, acrylonitrile, and acrylamide. 

The easiest technique to establish a polymer-photochromic molecule (PC) interaction is to dissolve the photochrome in a polymer solution from which the solvent is evaporated afterwards. DHI 7 has been incorporated by this technique into poly(methyl)- or poly( -butyl methacrylate), vinylidene chloride, acrylonitrile (Saran F), polycarbonate, and polystyrene-butadiene copolymer (Panarez). 

The DHI s may be solution cast with certain polymers. Examples of photochromic plastics prepared this way are poly (methyl methacrylate), poly (n-butyl methacrylate), copoly (vinylidene chloride-acrylonitrile) (e.g., SARAN F), polycarbonate, and polystyrene-butadiene (e.g., Panarez). 

Inverse gas chromatography, IGC, has been used to study water sorption of two poly (vinylidene chloride-vinyl chloride) and poly (vinylidene chloride-acrylonitrile) copolymers, at temperatures between 20 and 50°C and low water uptakes. It was found that the specific retention volume of water increases with decreasing amount of water injected, increases dramatically with decreasing temperature and strongly depends on the type of copolymer. Thermodynamic parameters of sorption namely free energy, entropy, enthalpy of sorption and activity coefficient were calculated. 

In this paper, the water sorption of two commercially available vinylidene chloride copolymers is studied using IGC at low probe concentrations. The copolymers are a poly (vinylidene chloride-vinyl chloride) copolymer (Saran B) and a poly (vinylidene chloride-acrylonitrile) copolymer (Saran F). These copolymers are extensively used in the form of films, coatings, and film laminates in various industrial applications (for example, packaging of foods and pharmaceuticals) where their diffusion characteristics are of prime importance. 

The copolymers investigated in the present study were both supplied by Polysciences, Inc., U.S.A. The first was polytvlnylldene chloride-vinyl chloride 80 20% w/w), having an average molecular weight (Mw) of 9xl04. The second was poly(vinylidene chloride-acrylonitrile, 80 20% w/w) of unknown molecular weight. 

Vinyl or vinylidene chloride/acrylonitrile copolymers Chlorosulphonated polyethylene, vulcanised chloroprene, chlorinated butyl rubber... 

The compositional analysis of a copolymer can be achieved by several methods other than NMR spectroscopy, such as elemental analysis, infrared and ultraviolet spectroscopies, and pyrolysis-gas chromatography. However, NMR spectroscopy has several advantages it does not need calibration if the operation conditions are properly set, and it can distinguish impurities easily. Quantitative aspects of compositional analysis by H and 13C NMR have been discussed for styrene-MMA copolymer12 and vinylidene chloride-acrylonitrile copolymer,13 respectively. 

Surface oxidation reactions have been carried out on a number of polymers, particularly polyethylene. Surface oxidation techniques include the use of corona discharge, ozone, hydrogen peroxide, nitrous acid, alkaline hypochloride, UV irradiation, oxidizing flame, and chromic acid The reactions lead initially to the formation of hydroperoxides, which catalyze the formation of aldehydes and ketones and finally, acids and esters. Surface oxidation treatment has been used to increase the printabdity of polyethylene and poly(ethylene terephthalate) and to improve the adhesion of polyethylene and polypropylene to polar polymers and that of polytetrafluoroethylene to pressure-sensitive tapes. Surface-oxidized polyethylene, when coated with a thin film of vinylidene chloride, acrylonitrile, and acryhc acid terpolymers becomes impermeable to oxygen and more resistant to grease, oil, abrasion, and high temperatures. The greasy feel of polyethylene has also been removed by surface oxidation. 

Since cellophane cannot melt, it is not heat-sealable. The many hydroxyl groups that it contains make it sensitive to water. It will not dissolve, but its properties can change markedly on exposure to moisture. For both these reasons, cellophane used in packaging is generally coated. Common types of coatings include vinylidene chloride-acrylonitrile copolymers, polyolefins, and mixtures of cellulose nitrate, wax, and resin. It may also have plasticizers added to improve its flexibility. 

Vinylidene chloride-vinyl chloride copolymers are used in the manufacture of filaments. The filaments have high toughness, flexibility, durability, and chemical resistance. They find use in car upholstery, deckchair fabrics, decorative radio grilles, doll hair, filter presses, and other applications. A flame-resisting fiber said to be a 50 50 vinylidene chloride-acrylonitrile copolymer is marketed by Courtaulds with the name Teklan. 

Diofan BASF Vinyl chloride—vinylidene chloride-acrylonitrile copolymers... 

Poly (vinylidene chloride-co-acrylonitrile). See Vinylidene chloride/acrylonitrile copolymer Poly (vinylidene chloride-co-methyl acrylate). See Vinylidene chloride/methyl acrylate copolymer... 

Stannous oleate Stearyl alcohol Styrene/MA copolymer Terpene resin Tetrahydrofuran Titanium dioxide Toluene Tosylamide/formaldehyde resin Triethylene glycol Urea-formaldehyde resin Vinylidene chloride/acrylonitrile copolymer Vinylidene chloride/methyl acrylate copolymer Vinylidene chloride/vinyl chloride copolymer Zinc laurate cellophane, food-contact Aluminum stearates Ammonium tallate Hexamethoxymethylmelamine Nonoxynol-55 Nonoxynol-70... 

Butadiene Styrene Vinyl acetate Vinyl chloride 2,5-Dichlorostyrene Methyl methacrylate Vinylidene chloride Acrylonitrile... 

Looking at the historical development of the emulsion pol)nnerization, it is seen that the trigger factor in this development was the necessity for synthetic rubber in the wartime. The production of styrene/butadiene rubber (SBR) satisfied this requirement. Today, millions of tons of S)mthetic latexes are produced by the emulsion pol3merization process for use in wide variety of applications. In the S)mthetic latexes, the most important groups are styrene/butadiene copolymers, vinyl acetate homopol)rmers and copol)nners, and polyacrylates. Other synthetic latexes contain copolymers of ethylene, styrene, vinyl esters, vinyl chloride, vinylidene chloride, acrylonitrile, cloroprene and polyurethane. 

Also known as lyl-dichloroethylene Vinylidene chloride-acrylonitrile copolymer n. Any VC co-polymer containing 5-15% acrylonitrile, and mainly used as... 

Acetone and methyl ethyl ketone are valuable solvent components in acrylic/nitrocellulose automotive lacquers. Acetone is the solvent of choice in film coatings operations which use vinylidene chloride-acrylonitrile copolymer formulations. Other ketones that may be used in these film coating operations... 

Polymer electrolytes are used in lithium ion rechargeable batteries. Pure polymer electrolyte systems include polyethylene oxide (PEO), polymethylene-polyethylene oxide (MPEG), or polyphosphazenes. Chlorinated PVC blended with a terpoly-mer comprising vinylidene chloride/acrylonitrile/methyl methacrylate can make a good polymer electrolyte. Rechargeable lithium ion cells use solid polymer electrolytes. Plasticized polymer electrolytes are safer than liquid electrolytes because of a reduced amount of volatiles and flammables. The polymer membrane can condnct lithinm ions. The polymer membrane acts as both the separator and electrolyte [7],... 

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