Methyl methacrylate, viii

Indenylidene compounds VIII, K, XXI, XXIII, XXVIIIa and XXVIIIb act as atom transfer radical polymerization catalysts for the polymerization of methyl methacrylate and styrene in high yields and with good control (Table 8.7). The catalytic activity can be dramatically improved by transforming the complexes into cationic species by treatment with AgBp4 [61]. 

The nature of the chlorinated reagent is crucial for promoting the Kharasch addition reaction (Equation 8.11). The results showed that carbon tetrachloride could be added to various olefins in a regioselective way. Under these reaction conditions, no polymerization products were detected. In contrast, when chloroform was used as the halide source the methyl methacrylate and styrene conversions reached only 33% and 40% with the best performing system (VIII), and a significant fraction of polymers was observed [61]. 

Table VIII lists some representative T0 values of unplasticized polymers. Very flexible polymers such as polyethylene, polyisoprene, polybutadiene, have low T0 values, whereas polymers with stiff backbone chains and bulky side groups, such as poly(methyl methacrylate) and polystyrene, have a high Tg. Clearly, it is a polymer with a high revalue where plasticization is most needed and where a significant lowering of Tg owing to the plasticizer may be expected.

VIII) indicated that replacement of acrylonitrile by methyl methacrylate did produce marked improvement in color stability during accelerated ... 

The use of l-acetyl-2-phenylhydrazine [APH (VI)] and saccharin resulted in a somewhat slower reaction rate than with DMPT unless a catalytic amount of copper was added. In this study the concentration of CHP was found to be very important where the molar ratio of CHP/APH was less than 1. Where the ratio was greater than 1, the rate was independent of CHP [12]. These papers [11,12] have been reviewed [13]. The accelerating effect of the salts of saccharin and 6-methyl-1,2,3,4-tetrahydroquinoline (VII), 1,2,3,4-tetrahydroquinoline (IV), or 1,2,3,4-tetrahydroquinaldine (VIII) on the anaerobic polymerization of methyl methacrylate were studied. No organic peroxides were required for these polymerizations [14]. 

High pressure fluid phase equilibrium data of poly(methyl methacrylate) in carbon dioxide and methyl methacrylate Data extract from Landolt-Bornstein VIII/6D3 Polymers, Polymer Solutions, Physical Properties and their Relations I (Thermodynamic Properties Equilibria of Ternary Polymer Solutions) ... 

Fukano K and Kageyama E, Study of radiation-induced polymerization of vinyl monomers adsorbed on inorganic substances. VIII. Polymerization of styrene and methyl methacrylate adsorbed on aerosiT, JPo/ym Sci Polym Chem 1976 14 2183-92. 

Such polymerization can be avoided by using a catalyst composed of a Group VIII metal or a derivative thereof, e.g., platinum (as platinum black or platinized asbestos or charcoal), hydrogen hexachloroplatinate, or ruthenium chloride then the 1 1 adducts can be obtained in good yield from olefins such as styrene, acrylonitrile, and methacrylic esters with, e.g., dichloro(methyl)-silane 347-349 nevertheless it is advantageous to exclude oxygen and add a polymerization inhibitor such as te/7-butylpyrocatechol or 2,6-di-terf-butyl-4-methylphenol. 

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