Vinylidene chloride-vinyl acrylonitrile

In addition to homopolymers of varying molecular and particle structure, copolymers are also available commercially in which vinyl chloride is the principal monomer. Comonomers used eommercially include vinyl acetate, vinylidene chloride, propylene, acrylonitrile, vinyl isobutyl ether, and maleic, fumaric and acrylic esters. Of these the first three only are of importance to the plastics industry. The main function of introducing comonomer is to reduce the regularity of the polymer structure and thus lower the interchain forces. The polymers may therefore be proeessed at much lower temperatures and are useful in the manufacture of gramophone records and flooring compositions. 

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. 

The first two modacrylic fibers ever introduced in the United States were Dynel (by Union Carbide) in 1949 and Verel (by Tennessee Eastman) in 1956. The former was a copolymer of 60 percent vinyl chloride and 40 percent acrylonitrile, and the latter was said to be a 50-50 copolymer of vinylidene chloride and acrylonitrile with perhaps a third component graft-copolymerized onto the primary material to secure dyeability. SEF and its version for wigs, Elura , were introduced by Monsanto Fibers in 1972. A few foreign manufacturers are making modacrylic fibers, but the only modacrylic fiber currently in production in the United States is SEF . 

Vinylidene chloride Vinyl acetate Styrene in 40% MeOH Acrylonitrile Acrolein... 

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. 

Use Manufacture of vinyl chloride vinylidene chloride vinyl acetate acrylates acrylonitrile acetaldehyde per- and trichloroethylene cyclooctatetraene 1,4-butanediol carbon black and welding and cutting metals. 

Acetylen Acetylene EINECS 200-816-9 Ethine Ethyne HSDB 166 Narcylen UN1001, An asphyxiant gas intermediate for manufacture of vinyl chloride, vinylidene chloride, vinyl acetate, acrylates, acrylonitrile, acetaldehyde, perchloroethylene trichloroethylene, 1,4-butanediol, carbon black, welding and cutting metals. Colorless gas mp = -81° d = 1,166 g/l (0°, 760 mm), d of gas = 0.90 (air = 1) soluble in H2O (1 1 v/v), soluble in AcOH, EtOH, Et20, CeHe, MezCO LC (rat inh) = 9000 ppm. Air Products Chemicals Inc. BASF Corp. BOC Gases Union Carbide Corp. 

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. 

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. 

Saran Dow Copolymers of vinylidene chloride, vinyl chloride and acrylonitrile... 

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... 

FIB Poly(hexalluoroisopropyl methacrylate-co-hepta-fluoro- -butyl methacrylate), PBTS Poly (4-t-butyl styrene), PVC Poly(vinyl chloride), PV /C/-PdJVPoly(vinylidene chloride-co-acrylonitrile) Luminescence lifetime response... 

Styrene Vinyl naphthalene Vinyl acetate Acrylonitrile a-Methyl styrene Vinylidene chloride Vinyl chloride... 

Of critical importance, analysis of poly(methyl methacrylate) (PMMA) showed that at a saturation temperature, T, of 40°C, a saturation pressure, P%, of 1,500 psig (at these conditions, carbon dioxide is considered a supercritical fluid), and a saturation time, ts, of 24 h, a 1 mm thick disk absorbed 16.4 wt% carbon dioxide. Additionally, at a foaming temperature, Tf, of 120°C and a foaming time, tf, of 1 min, PMMA had a stable volumetric expansion ratio of 20. Other polymers also absorbed significant quantities of carbon dioxide, such as polystyrene (PS) and poly(vinylidene chloride-co-acrylonitrile) (P(VDC-AN)), which absorbed 8.9 and 2 wt% carbon dioxide, respectively, yet the stable foams that were formed had expansion ratios of less than 2 at the same conditions used to form the PMMA samples. Another polymer poly(vinyl methyl ketone) (PVMK) achieved an expansion ratio of 20. However, the foams were unstable, readily collapsed, and exhibited large voids ( 5 mm diameter), which are inconsistent with microcellular foams. The fact that PVMK readily collapsed after the foaming process made it difficult to determine the concentration of carbon dioxide in the sample. These results led to the eventual incorporation of the MMA monomer into the polymer formulation from the standpoint of carbon dioxide-induced microcellular foamability. 

Fig. 13. Variation of the interaction parameter (%) with PCL contents of blends of PCL with several Saran copolymers ( ) vinylidene chloride-vinyl chloride copolymer, (O)vinyli-dene chloride-acrylonitrile copolymer, ( ) vinylidene chloride-vinyl acetate copolymer data taken from [74]...

Butadiene/acrylonitrile (vinylidene chloride)//vinyl chloride) Poly(vinyl chloride) 137)... 

Methyl acrylate Vinylidene chloride Vinyl fluoride Styrene Acrylonitrile Styrene... 

Modacryl ic fibers are formed from copolymers consisting of 35%85% acrylonitrile and a suitable vinyl comonomer or comonomers such as vinyl chloride, vinylidene chloride, vinyl acetate, vinyl pyrollidone, or methyl acrylate. The modacrylics generally resemble acrylics and have a warm pleasing hand and good drapability, resiliency and wrinkle resistance. They are more heat sensitive but more flame resistant than acrylics and have generally been used in specialty applications. Modacrylic fiber exhibits a more thermoplastic character than the related acrylic fibers. 

The PVDC homopolymer is difficult to process. Thus, copolymers of vinylidene chloride-vinyl chloride, vinylidene chloride-alkyl acrylate, vi-nylidene chloride - acrylonitrile, which are easier to process than PVDC homopolymer, are widely used in industrial processes. The choice of comonomer significantly affects the properties of the copolymer. Table 8 illustrates the reactivity ratios of some important monomers (monomer 1 = VDC) [76]. 

Acrylonitrile-butadiene-styrene (ABS) terpolymer. Acrylonitrile and styrene are grafted on polybutadiene. It is preferred over homopolymers because of impact resistance, dimensional stability and good heat-distortion resistance. It is an extremely important commercial copolymer and, in several applications, it is blended with other polymers (e.g., PVC or polycarbonates) in order to increase their heat-distortion temperatures. When methyl methacrylate and styrene are grafted on polybutadiene, a methyl methacrylate-butadiene-styrene MBS copolymer is formed. Vinylidene chloride-vinyl chloride copolymer. Because of its toughness, flexibility, and durability, the copolymer is used for the manufacture of filaments for deck chair fabrics, car upholstery, and doll s hair. Biaxially stretched copolymer films are used for packaging. 

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