Poly vinyl halides

Poly(vinyl halides).— Vink and Van Bloois have reviewed the general mechan- [Pg.531]

Mathur, V. Kumar, and G. N. Mathur, Ind. Polym. Radiat., Proc. Symp., 1979, 143. [Pg.531]

Dorofeev and V. E. Skurat, Dokl. Akad. Nauk. SSSR, 1979, 249, 1142. [Pg.531]

Canaback, and B. Ranby, J. Appl. Polym. Sci., Appl. Polym. Symp., 1979, 35, 299. J. F. Rabek, B. Ranby, B. Ostcnsson, and P. Flodin, J. Appl. Polym. Sci., Appl. Polym. Symp., 1979, 35, 299. [Pg.532]

Other studies of interest on PVC photo-oxidation include the influence of light intensity,chlorination, solvent diffusion,and inhibition of dehydrochlorination at the surface layers.The chlorination process destabilized the PVC. [Pg.534]

2 Poly(vinyl halides) - Photodehydrochlorination occurs in PVC with a foam backing as determined by Raman spectroscopy. For PVC stabilised with Zn/Ca stearates phooxidation indicates that dehydrochlorination dominates over oxidation at the inner layers beyond 100 microns . The effect of polyene formation also appears to be a function of light intensity as well as oxygen diffusion rate. [Pg.358]

Photothermal dehydrochlorination of PVC as studied by derivative ultraviolet absorption and fluorescence analysis techniques has shown that carbonyl and hydroperoxide groups are more important in the initiation steps than [Pg.489]

Low molecular weight waxes were found to be weak sensitisers. The photostability of plasticised PVC is [Pg.489]

The trapping of hydroxy radicals was considered to be the best way of protecting the polymer. In another study it was found that PVC photooxidation was a non-uniform [Pg.491]

Koshechko, V.G., Titov, V.E. and Sednev, D.V. (1994) New route for producing acrylic add copolymers, based on electrochemical carboxylation of poly(vinyl halide)s and polybutadiene. Polymer 35, 1787-1788. [Pg.302]

DBU and its salts have been patented and used as dehydrohalogenation agents for fluoropolymers (83JAP(K)219202), fluororubbers (78MI3), and poly(vinyl halide) in the preparation of polarizing films (83JAP(K)21929), and as dissociation catalysts for blocked isocyanates (83JAP(K)65764). [Pg.142]

Application of the Computer to Degradation Kinetics of Poly(vinyl Halides)... [Pg.377]

Computer programs have been used to correlate the degradation kinetics of poly(vinyl halides) assuming a kinetic model that is based on the zipper mechanism. Best fit values of the parameters of the kinetic model allow reproduction of a degradation with an error that is usually less than 0.6% per point. [Pg.377]

The storage of voluminous run data in a readily available form and the obtaining of best fit values of kinetic parameters have been useful in the better understanding of the degradation kinetics of poly(vinyl halides). ... [Pg.382]

Poly(vinyl halides) - The photocatalysed oxidation of PVC has been undertaken in the presence of titanium dioxide and zinc oxide pigments and the extent of dehydrochlorination measured. Acetic and formic acids were major products along with carbon dioxide. Copper(II) dialkyldithiocarbamate complexes are also sensitisers. Photodegradable PVC has also been developed by grafting with benzophenone chromophores. Plasticised PVC also degrades and discolours on irradiation but this is due mainly to the plasticiser. ... [Pg.378]

Modifications of chloromethyl substituted polystyrene and poly(vinyl halides). [Pg.27]

Poly(vinyl halide) Acrylic N-methylol acrylamide in acrylic Dielectric sealing Yannich and Katz U.S. Pat., 4,684,689, 1989 National Starch... [Pg.430]

Poly(vinyl halides) (PVC etc.) and PoIy(vinyl alcohol) (PVA).—A series of papers has appeared concerned with the photo-dehydrochlorination, discoloration, and sensitized photolysis of model compounds of PVC,819 and its copolymers.220 The photolysis of poly(vinyl bromide)221 and a trifluorochloroethylene-vinylidene fluoride copolymer228 has been described. The photo-oxidative destruction of PVA has been reported in a series of papers.223... [Pg.532]

This section deals with paints based on vinyl resins (including vinyl copolymers) which are synthesized by polymerization of monomers containing terminal CH2 = CH groups. Polyolefins, poly(vinyl halides) and vinyl halide copolymers, poly(vinyl esters), poly(vinyl alcohol), poly(vinyl acetals), poly(vinyl ethers), and polystyrene are discussed. Polyacrylates (acrylic resins) are treated in Section 2.5. [Pg.23]

Poly(Vinyl Halides) and Vinyl Halide Copolymers... [Pg.25]

Poly(l-haloethylene) Poly(vinyl halide) -[XCHCH2]-Poly(l-cyanoethylene) Poly(acrylonitrile) -[NCCHCH2]-... [Pg.2190]

Qin, M. F. Head to Head Vinyl Polymers Head to Head Poly(vinyl halides) and Chiral Crystallization. Dissertation, Polytechnic University, 1995. [Pg.938]

Polyvinyl compounds are produced either by the polymerization of vinyl compounds CH2=CHX or by polymer analog reactions on polyvinyl compounds. The derivatives of poly(vinyl alcohol) -%CH2—CH(OHH- , poly(vinyl halides) -f-CH2—CHHal and poly-(vinyl amines) -%CH2—CH(NRiR2)- are of particular commercial importance. In contrast to these, poly(vinyl sulfides) -f-CH2—CH(SR)- are only of academic interest. Vinyl alcohol is unstable, since it transforms into acetaldehyde on formation. Therefore, poly(vinyl alcohol) is produced from poly(vinyl acetate). [Pg.902]

Poly(vinyl halides) and poiy(vinyl nitriles) ... [Pg.148]

Polyisobutylene of low molecular weight was synthesized by a Wurtz type reaction from l,4-dibromo-2,2,3,3 tetramethylbutane. Polyacrylates were obtained from alternating copolymerization of symmetric internal olefins or ethylene with maleic anhydride followed by quantitative esterification. Poly(vinyl halides) were prepared from cis-1,4-polybutadiene by chlorination (H-H PVC) or bromin-ation (H-H PrBr). The polymers were characterized and their chemical, thermal, degradation solution, melt and blending behavior was studied. [Pg.35]

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