Vinyl acetate-versatic acid

They include vinyl acetate homopolymers and all copolymers in which vinyl acetate is the major constituent (50% or greater). The major PVAc copolymers are vinyl acetate-ethylene (VAE) and vinyl acetate-acrylic ester (vinyl acrylic). Vinyl acetate-versatic acid (vinyl versatate) and vinyl acetate- maleate are major PVAc copolymer emulsions used. 

These investigations were concentrated on the vinyl ester of Versatic 911, the acid derived from C8-Ci0 olefins. This product will be referred to further as W 911. The copolymerization of VV 911 with vinyl acetate, especially the emulsion copolymerization, was studied extensively. This paper describes the copolymerization characteristics of VV 911, a process developed for latex manufacture, and the reasons for its excellent reproducibility. 

Alternative processes include the vinyl esters cf "Versatic acid" (shell Chemicals), with vinyl acetate and acrylamide (49 49 2), which are added gradually after conversion to a pre-emulsion, to an anionic surfactant solution containing a persulfate. Transt parent waterproof films are formed. 

Vinyls, finyl esters are usually used in waterborne coatings in the form of copolymer dispersions. Typical vinyl esters are vinyl acetate, vinyl propionate, vinyl laurate, and vinyl versatate. Acrylic, maleic, and fumaric acid esters are used as copolymers, finyl acetate is lower in cost compared to (meth) acrylic esters. Although vinyl acetate coatings are inferior to acrylics in both photochemical stability and resistance to hydrolysis, this does not prevent them from being used for exterior... 

Poly(vinyl ester) dispersions are quantitatively more important than solid resins. Homopolymer and copolymer dispersions are used for binders in emulsion (dispersion) paints, plastic-bonded plasters, and water-thinnable adhesives. Poly(vinyl acetate) dispersions are less important than vinyl acetate copolymer dispersions. The most important comonomers of vinyl acetate are vinyl laurate, dibutyl maleate, Versatic Acid esters (VeoVa, Shell), ethylene, vinyl chloride, and butyl acrylate. Poly(vinyl propionate) and copolymers of vinyl propionate with butyl acrylate, styrene, or vinyl chloride are also marketed and used as dispersions. 

Poly(vinyl acetate) dispersions form lightfast, dry, hard, brittle films. Plasticizers therefore have to be used (external plasticization), which are, however, volatile and lead to embrittlement of the films after a relatively short time. Internally plasticized dispersions of copolymers of vinyl acetate with vinyl laurate, butyl maleate, Versatic Acid esters, or ethylene form permanently flexible, nonaging films that are not, however, always sufficiently resistant to hydrolysis. Terpolymer (vinyl acetate-ethylene-vinyl chloride) dispersions form films that are more resistant to hydrolysis than homopolymer and copolymer dispersions. The films also have a higher mechanical strength and lower flammability. The glass transition temperature of the terpolymer can be varied within wide limits and properties can be matched to requirements by using a suitable choice of comonomers. The same is true of vinyl propionate copolymer dispersions. 

Vinyl acetate copolymers are used worldwide in polymer dispersions. Copolymers with dibutyl maleate are particularly elastic, while copolymers with vinyl esters of Versatic Acid have particularly good weather resistance for shade formulations. Copolymers with acrylate esters and vinyl acetate-ethylene-vinyl chloride terpoly-mers with a good cost - performance ratio are also important. 

Vinyl acetate is relatively inexpensive and is readily copolymerized with vinyl chloride, ethylene, acrylates and methacrylates. The monomer is a colourless, flammable liquid with an initial pleasant odour, which on exposure becomes irritating. One of the major disadvantages of vinyl acetate-based copolymers is their poor hydrolytic and UV stability. This was shown to improve when copolymerized with vinyl esters of versatic acid [18]. Copolymers of vinyl acetate with the vinyl esters of versatic acid have been used in Europe for the last quarter-century. In the US similar monomers were introduced in the past five years, two of which are illustrated in Table 6.1, namely, vinyl pivalate and vinyl neo-decanoate. More details of the copolymerization of these monomers with vinyl acetate is given in Chapter 16. 

Vinyl acetate/vinyl Versatate 42-00 FILM FORMER Methyl methacrylate/ethyl acrylate/acrylic acid latex 26-00... 

As noted in Section 6.5.2, the hydrolysis resistance of latex films from emulsion polymers prepared from the vinyl acetate (VA) monomer is marginal for ontdoor use. In Europe and recently in the United States, vinyl versatate (II) (Ri = —CH2CH2CH2CH2CH2CH2CH3 and R2 = R3 = —CH3) has been introduced for use along with vinyl acetate for improved outdoor performance of latex coatings. Vinyl versatate is the vinyl ester of versatic acid, a 10-carbon carboxylic acid of the highly branched structure sometimes called neo ... 

Vinyl acetate (VAc) (acetic acid ethenyl ester) [108-05-4] is less expensive than (meth)acrylate monomers. VAc latexes are inferior to acrylic latexes in photochemical stability and resistance to hydrolysis and are used in flat wall paints. Reference 119 discusses use of a variety of vinyl esters in latexes. The polymers are more hydrophobic than VAc homopolymers and have superior hydrolytic stability and scrub resistance. Reference 120 reports the advantages of using vinyl versatate in both VAc and acrylic copolymers. 

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