Vinylidene chloride-methacrylate

Vinylidene chloride Methacrylate, 2-(sulfonic acid)ethyl 0.22 3.6 564... 

Comparison of Table 5.4 and 5.7 allows the prediction that aromatic oils will be plasticisers for natural rubber, that dibutyl phthalate will plasticise poly(methyl methacrylate), that tritolyl phosphate will plasticise nitrile rubbers, that dibenzyl ether will plasticise poly(vinylidene chloride) and that dimethyl phthalate will plasticise cellulose diacetate. These predictions are found to be correct. What is not predictable is that camphor should be an effective plasticiser for cellulose nitrate. It would seem that this crystalline material, which has to be dispersed into the polymer with the aid of liquids such as ethyl alcohol, is only compatible with the polymer because of some specific interaction between the carbonyl group present in the camphor with some group in the cellulose nitrate. 

A number of other copolymers with vinylidene chloride as the major component have been marketed. Prominent in the patent literature are methyl methacrylate, methyl acrylate and ethyl acrylate. 

Poly(ethylene terephtlhalate) Phenol-formaldehyde Polyimide Polyisobutylene Poly(methyl methacrylate), acrylic Poly-4-methylpentene-1 Polyoxymethylene polyformaldehyde, acetal Polypropylene Polyphenylene ether Polyphenylene oxide Poly(phenylene sulphide) Poly(phenylene sulphone) Polystyrene Polysulfone Polytetrafluoroethylene Polyurethane Poly(vinyl acetate) Poly(vinyl alcohol) Poly(vinyl butyral) Poly(vinyl chloride) Poly(vinylidene chloride) Poly(vinylidene fluoride) Poly(vinyl formal) Polyvinylcarbazole Styrene Acrylonitrile Styrene butadiene rubber Styrene-butadiene-styrene Urea-formaldehyde Unsaturated polyester... 

T after the name of the fibre stands for thioamidated . CL-fibre previously crosslinked with ZnO. Crotylan - fibre from AN copolymer with 3-chloro-2-butenyl methacrylate. Caniv -fibre from AN copolymer with vinylidene chloride. 

In addition, Bamford, Jenkins and coworkers (19) previously reported on the behavior of occluded radicals in the heterogeneous polymerizations of acrylonitrile, methyl acrylate, methyl methacrylate and vinylidene chloride. From their electron spin resonance studies, they concluded that the degree of occlusion was ... 

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 ... 

A third factor influencing the value of Tg is backbone symmetry, which affects the shape of the potential wells for bond rotations. This effect is illustrated by the pairs of polymers polypropylene (Tg=10 C) and polyisobutylene (Tg = -70 C), and poly(vinyi chloride) (Tg=87 C) and poly(vinylidene chloride) (Tg =- 19°C). The symmetrical polymers have lower glass transition temperatures than the unsymmetrical polymers despite the extra side group, although polystyrene (100 C) and poly(a-meth-ylstyrene) are illustrative exceptions. However, tacticity plays a very important role (54) in unsymmetrical polymers. Thus syndiotactic and isoitactic poly( methyl methacrylate) have Tg values of 115 and 45 C respectively. 

List C contains peroxidisable monomers, where the presence of peroxide may initiate exothermic polymerisation of the bulk of material. Precautions and procedures for storage and use of monomers with or without the presence of inhibitors are discussed in detail. Examples cited are acrylic acid, acrylonitrile, butadiene, 2-chlorobutadiene, chlorotrifluoroethylene, methyl methacrylate, styrene, tetraflu-oroethylene, vinyl acetate, vinylacetylene, vinyl chloride, vinylidene chloride and vinylpyridine [1]. 

Acrylic fibers. Acrylic fibers are polymers of acrylonitrile and another chemical. When acrylonitrile is 85% or more of the polymer, the fiber is called acrylic. If there s more copolymer so the percentage of acrylonitrile decreases to 35-85%, the fiber is called modacrylic. Some of the popular monomers used as copolymers are methyl acrylate and methacrylate, acrylamide, vinyl acetate, vinylidene chloride, and vinyl chloride, Dynel is 40% acrylo and 60% vinyl chloride. 

Polymers such as polystyrene, poly(vinyl chloride), and poly(methyl methacrylate) show very poor crystallization tendencies. Loss of structural simplicity (compared to polyethylene) results in a marked decrease in the tendency toward crystallization. Fluorocarbon polymers such as poly(vinyl fluoride), poly(vinylidene fluoride), and polytetrafluoroethylene are exceptions. These polymers show considerable crystallinity since the small size of fluorine does not preclude packing into a crystal lattice. Crystallization is also aided by the high secondary attractive forces. High secondary attractive forces coupled with symmetry account for the presence of significant crystallinity in poly(vinylidene chloride). Symmetry alone without significant polarity, as in polyisobutylene, is insufficient for the development of crystallinity. (The effect of stereoregularity of polymer structure on crystallinity is postponed to Sec. 8-2a.)... 

Many other copolymers of commercial importance have been discussed previously see Secs. 3-14c (vinyl acetate, vinylidene chloride), 3-14d (acrylic and methacrylic acids and esters,... 

For disubstituted ethylenes, the presence and type of tacticity depends on the positions of substitution and the identity of the substituents. In the polymerization of a 1,1-disubstituted ethylene, CH2=CRR, stereoisomerism does not exist if the R and R groups are the same (e.g., isobutylene and vinylidene chloride). When R and R are different (e.g., —CH3 and —COOCH3 in methyl methacrylate), stereoisomerism occurs exactly as in the case of a monosubstituted ethylene. The methyl groups can be located all above or all below the plane of the polymer chain (isotactic), alternately above and below (syndiotactic), or randomly (atactic). The presence of the second substituent has no effect on the situation since steric placement of the first substituent automatically fixes that of the second. The second substituent is isotactic if the first is isotactic, syndiotactic if the first substituent is syndiotactic, and atactic if the first is atactic. 

In 1838 Regnault [15] reported that vinylidene chloride could be polymerized. In 1839 Simon [16] and then Blyth and Hofmann (1845) [17] reported the preparation of polystyrene. These were followed by the polymerization of vinyl chloride (1872) [18], isoprene (1879) [19], methacrylic acid (1880) [20], methylacrylate (1880) [21], butadiene (1911) [22], vinyl acetate (1917) [23], vinyl chloroacetate [23], and ethylene (1933) [24]. Klatte and Rollett [23] reported that benzoyl peroxide is a catalyst for the polymerization of vinyl acetate and vinyl chloroacetate. 

Monomers with relative rates between 1 and 5 (acrylonitrile, vinylidene chloride, chloroprene, and short-chain methacrylates). 

Polymerization and Spinning Solvent. Dimethyl sulfoxide is used as a solvent for the polymerization of acrylonitrile and other vinyl monomers, eg, methyl methacrylate and styrene (82,83). The low incidence of transfer from the growing chain to DMSO leads to high molecular weights. Copolymerization reactions of acrylonitrile with other vinyl monomers are also tun in DMSO. Monomer mixtures of acrylonitrile, styrene, vinylidene chloride, medially sulfonic acid, styrenesulfonic acid, etc, are polymerized in DMSO—water (84). In some cases, the fibers are spun from the reaction solutions into DMSO—water baths. 

By chemical agents, indirect grafting on Nylon in liquid phase is frequently referred to in the bibliography. The most common reagent is air (144) or ozone, under controlled conditions, in order to avoid deterioration on the mechanical properties of the fiber, which is then immersed in the monomer. Hence, styrene (145-149), vinylidene chloride (146), vinyl acetate (146), acrylic and methacrylic acids (149), methyl methacrylate (146), acrylonitrile (146,148,149), 2-methyl-5-vinylpyridine (149) were successfully employed as grafting comonomers. 

Many synthetic laiices exist. They contain butadiene and. styrene copolymers telasioiiieric). styrene - butadiene copolymers ireximms). butadiene and acrylonitrile, chloroprene copolymers, methacrylate and acrylate ester copolymers, vinyl aeelate copolymers, vinyl and vinylidene chloride copolymers, ethylene copolymers. Huorinated copolymers, acrylamide copolymers, styrene-acrolein copolymers, and pyrrole and pyrrole copolymers. Yluny of these lattee.s also have earboxylated versions. 

For ambient or low temperature application, thermoplastic polymers can be used. Low cost monomers that have been used in this category include ethylene, ethylene-S02, vinyl acetate, methyl methacrylate, styrene, styrene-acrylonitrile, and chlorostyrene. Others awaiting test are vinyl chloride, vinylidene chloride, and terf-butylstyrene. These monomers are limited for use at temperatures below / 100°C because of their softening points. 

Vinylidene chloride copolymerizes randomly with methyl acrylate and nearly so with other acrylates. Very severe composition drift occurs, however, in copolymerizations with vinyl chloride or methacrylates. Several methods have been developed to produce homogeneous copolymers regardless of the reactivity ratio (43). These methods are applicable mainly to emulsion and suspension processes where adequate stirring can be maintained. Copolymerization rates of VDC with small amounts of a second monomer are normally lower than its rate of homopolymerization. The kinetics of the copolymerization of VDC and VC have been studied (45—48). 

Vinyl chloride can be copolymerized with a series of monomers Vinylidene chloride, trans-dichloroethylene, vinylesters of aliphatic carboxylic acid (C2-C18), acrylic acid esters, methacrylic and/or maleic acid as well as fumaric acid with mono-functional aliphatic saturated alcohols (Cj-C18), mono-functional aliphatic unsaturated alcohols (C8—C18), vinyl ethers from mono-functional aliphatic saturated alcohols (C i-Cis), propylene, butadiene, maleic acid, fumaric acid, itaconic acid, acrylic acid, methacrylic acid (total < 8 %) and N-cyclohexylmaleinimide (< 7 %). 

T he free radical initiated polymerization of polar monomers containing pendant nitrile and carbonyl groups—e.g., acrylonitrile and methyl methacrylate—in the presence of metal halides such as zinc chloride and aluminum chloride, is characterized by increased rates of polymerization (2, 3, 4, 5,10, 30, 31, 32, 33, 34, 53, 55, 65, 66, 75, 76, 77, 87). Imoto and Otsu (30, 33, 34) have attributed this effect to the formation of a complex between the polar group and the metal halide. The enhanced reactivity of the complexed monomer extends to copolymerization with uncomplexed monomers, such as vinylidene chloride, which are readily responsive to... 

The most significant observation in the radical copolymerization of methyl methacrylate with vinylidene chloride in the presence of zinc chloride is the increase in the Q and e values of methyl methacrylate, the increase in the rx value of methyl methacrylate, and the decrease in the r2 value of vinylidene chloride (30). Although it has been proposed that these results arise from the increased reactivity of the complexed methyl methacrylate monomer, a more likely explanation is the homopolymerization of a methyl methacrylate-complexed methyl methacrylate complex accompanied by the copolymerization of methyl methacrylate with vinylidene chloride. 

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). 

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