Copolymerization of vinyl chloride

Random copolymers of vinyl chloride and other monomers are important commercially. Most of these materials are produced by suspension or emulsion polymerization using free-radical initiators. Important producers for vinyl chloride—vinyUdene chloride copolymers include Borden, Inc. and Dow. These copolymers are used in specialized coatings appHcations because of their enhanced solubiUty and as extender resins in plastisols where rapid fusion is required (72). Another important class of materials are the vinyl chloride—vinyl acetate copolymers. Principal producers include Borden Chemicals Plastics, B. F. Goodrich Chemical, and Union Carbide. The copolymerization of vinyl chloride with vinyl acetate yields a material with improved processabihty compared with vinyl chloride homopolymer. However, the physical and chemical properties of the copolymers are different from those of the homopolymer PVC. Generally, as the vinyl acetate content increases, the resin solubiUty in ketone and ester solvents and its susceptibiUty to chemical attack increase, the resin viscosity and heat distortion temperature decrease, and the tensile strength and flexibiUty increase slightly. 

Up to this point we ve discussed only homopolymers—polymers that are made up of identical repeating units, in practice, however, copolymers are more important commercially. Copolymers are obtained when two or more different monomers are allowed to polymerize together. For example, copolymerization of vinyl chloride with vinylidene chloride (1,1-dichloroethylene) in a 1 4 ratio leads to the polymer Saran. 

Carbonyl Groups. Such structures could be introduced by air oxidation during polymerization or subsequent processing of the polymer. There is, in fact, some experimental evidence for their formation during polymerization via the following sequence of steps (6) (1) copolymerization of vinyl chloride with adventi-... 

The stabilizing effect of organotin compounds can also be used for internal stabilization. In this respect, a French patent of 1957 suggests copolymerization of vinyl chloride with small amounts of a vinyltin compound (e.g., the vinyldiethyl laurate of tin), which considerably improves the thermal stability over homopolymeric vinyl chloride (8). An American patent of 1959 suggests two types of organotin compounds as stabilizers (13) ... 

Copolymerization of vinyl chloride with metal salts of unsaturated carboxylic acids has been investigated more closely. By radical copolymerization in methanol solution of vinyl chloride and lead acrylate small amounts of lead acrylate can be inserted into the copolymer chains. However, only about one-third to one-half of the lead salt originally present in the monomer mixture is incorporated in the chains. Moreover, the thermal stability of the resulting polymer shows only a relatively small improvement over that of homopolymeric vinyl chloride (1) (see Figure 4). Although the rate of dehydrochlorination is distinctly lowered with increasing lead content in the polymers, there is no induction period at the onset of thermal treatment. Therefore, one cannot speak of true stabilization in this case. 

Both rate equations (147) and (150) were tested by Matsuo and Stockmayer for the copolymerization of vinyl chloride with vinylidene chloride [223]. They found that this case is adequately described not only by the general form (147) but even by the simplified shape (150). 

In the copolymerization of vinyl chloride and vinyl acetate, what monomer feed composition is needed to produce a copolymer containing 5 mol % vinyl acetate (The reactivity ratios are listed in Table 7-1.)... 

An example is the random copolymer made by free radical copolymerization of vinyl chloride and vinyl acetate ... 

Recent investigations [259] have indicated that the polymerization is not conventional free radical in character but is likely to be coordinated anionic. In support of this view are the reactivity ratio coefficients in copolymerization of vinyl chloride with vinyl acetate and methyl methacrylate, which are different from those found with free radical initiators. 

Poly(vinyl chloride) may also be internally plasticized by copolymerization of vinyl chloride with vinyl acetate, as mentioned earlier. It is not possible to obtain the same result from a mixture of the same proportions of PVC and poly(vinyl acetate) homopolymers. Incorporation of vinyl acetate into the polymer chains produces the intimate association of components needed to lower the temperature required for processing in much the same way as an added plasticizer does. Important end uses for poly(vinyl chloride-co-vinyl acetate) at low levels of vinyl acetate incorporation are phonograph records and floor tiles, and also for sheeting, when added filler will also be used. 

History of Production Manufacture of Vinyl Chloride Monomer Polymerization of Vinyl Chloride Copolymerization of Vinyl Chloride Characterization of Poly(vinyl chloride)... 

Copolymerization of Vinyl Chloride and Allyl 10,1 l-Dibromo-undecanoate and... 

Uses Initiator for polymerization and copolymerization of vinyl chloride, acrylates, methacrylates, polyester Trade Name Synonyms Aztec BCHPC [Aztec Peroxides] Aztec BCHPC-40-SAQ [Aztec Peroxides] Aztec BCHPC-75-W t[Aztec Peroxides] Perkadox 16 t[Akzo Nobel http //www.akzonobel.com], Perkadox 16/35 t[Akzo Nobel http //www.akzonobel.com] Perkadox 16N t[Akzo Nobel http //www.akzonobel.com], Perkadox 16S f[Akzo Nobel http //www.akzonobel.com]-, Perkadox 16-W25-GB1 f[Akzo Nobel http //www.akzonobel.com], Perkadox 16/W40 [Akzo Nobel http //www.akzonobel.com]. 

A polymer consisting of a single kind of monomer is called a homopolymer. A polymer manufactured from more than one kind of monomers is a copolymer. The most frequent copolymerization processes use two monomers (e. g. copolymerization of vinyl chloride with vinyl acetate, styrene with butadiene, etc.). If a polymer contains three different monomers, it may be called a terpolymer. The most common terpolymer is ABS consisting of acrylonitrile, butadiene, and styrene. 

Copolymerization of vinyl chloride with 3%-20% vinyl acetate in acetone or dioxan solution, or in the precipitant, hexane, yields products soluble in lacquer solvents. Copolymers of vinyl chloride with 15% vinyl acetate are used as HiFi phonograph records. 

In the free radical copolymerization of vinyl chloride with 3%-10% propylene, the propylene must be added regularly during the copolymerization in order to reduce the constitutional inhomogeneity. Propylene incorporation hinders the unzipping dehydrochlorination mechanism. These... 

Copolymerization of vinyl chloride with unsaturated benzoxazolone derivatives produces a copolymer belonging to the class of self-stabilized polymers. In comparison with PVC, these copolymers have increased thermo-oxidative stability. The maximum effect of stabilization is gained at a content of up to 2 mol%. 

Bunten [144] has briefly reviewed the polymerization kinetics of the emulsion copolymerization of vinyl chloride. He also discussed the formation and applications of plastisols—one of the major uses of PVC-emulsion polymers. 

Seeded Emulsion Copolymerization of Vinyl Chloride and Ethylene with Acrylic Acid [165]... 

Commercially, only a very small proportion of the total production of PVC is carried out in solution. The cost of the solvent and of solvent recovery makes the process unattractive. Its primary application is in certain processes such as the copolymerization of vinyl chloride with vinyl acetate (10-25% vinyl acetate) or the terpolymerization of vinyl chloride-vinyl acetate and certain maleates. The resultant polymer solutions are valuable coating materials [1]. The solution processes are said to produce highly uniform copolymers with narrow molecular weight distributions [1,167]. 

Copolymerization of vinyl chloride, a higher alkyl acrylate, and acrylonitrile by suspension [252]. 

Graft copolymerization of vinyl chloride onto poly(vinylpyrrolidone) [254]. 

Vinyl Chloride Plastics n These are plastics based on reins prepared by the polymerization of vinyl chloride or copolymerization of vinyl chloride with other unsaturated compounds, vinyl chloride being in greatest amount by mass Handbook of Polyvinyl Chloride Formulating, Wickson, E. J., ed., John Wiley and Sons, Inc., New York, 1993). See Polyvinyl Chloride. 

In a different binary (vinyl chloride-MA) and ternary (vinyl chloride-MA-butadiene) copolymerization study, equimolar copolymerization of vinyl chloride and MA does not appear to be a general rule. The formation of equimolar copolymer appears restricted to limited cases, such as very low conversion and sufficiently high MA vinyl chloride ratios in the monomer feed. It is very hard to see how vinyl chloride, a weak acceptor, could become a donor monomer in the presence of the strong acceptor MA and a CTC formed from the monomer pair regulate copolymerization to obtain 1 1 alternating copolymer. The authors are inclined to agree with Ring s evaluation of this monomer pair. 

The aim of this review is to summarize and discuss the kinetic data of the emulsion polymerization and copolymeiization of vinyl chloride. The current understanding of the kinetics of free-radical polymerization of conventional monomer is briefly described and kinetic data of radical polymerization and copolymerization of vinyl chloride in the presence of hydrophobic and hydrophilic additives are summarized. Efiects of the initiator type and concentration, the reaction conditions and the type of diluent are evaluated. Variation of kinetic and molecular weight parameters in the heterogeneous polymerizations with emulsifier type and concentration are discussed. 

Fig. 9. Variation of the total monomer conversion in the emulsion copolymerization of vinyl chloride and butyl acrylate with the reaction time and with the mole fraction of vinyl chloride, [158], Xyj, 0.34(O), 0.67 ( ), 0.89 ( ), 0.95 (A), 1.0 ( ). Recipe 300 g water, 200 g monomer, 14.8 g Dowfax 2A1, 0.342 g ammonium peroxodisulfate, 0.075 g NaHCOj, 60 °C...

Table 10. Variation of kinetic, colloidal and molecular weight parameters in the emulsion copolymerization of vinyl chloride with the mole fraction of vinyl chloride, [158]...

Vinyon is formed by emulsion polymerization of vinyl chloride or by copolymerization of vinyl chloride with less than 15%vinyl acetate in the presence of free radical catalysts to a DP of 200 50 ... 

Shaglaeva, N.S., O.V. Lebedeva, Yu.N. Pozhidaev et al. 2008. Copolymerization of vinyl chloride with l-vinyl-4,5,6,7-tetrahydroindole and 2-methyl-5-vinylpyridine. Vysokomol Soed B 50 (11) 2035-2041. 

In the case of diisopropyl peroxydicarbonate [159], an 80-20 20-80 mixture of partidly saponified poly(vinyl acetate) and a cellulose ether was used as the dispersing agent. The suspension polymerization or copolymerization of vinyl chloride was carried out in the presence of a compound having a -SH, -OH, or -CO2H groups in order to reduce the amount of chain transfer agent required. 

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