Monomers magnesium acrylate

Synonyms 2-Propenoic acid, polymer with ethene, magnesium salt Definition Copolymer of ethylene and magnesium acrylate monomers Famula (C3HA CjH,), xMg... 

Using magnesium ether carboxylates as emulsifier a porous polyvinylchloride can be made [218] and a propoxylated ether carboxylate is described as emulsifier to make an ethyl acrylate-styrene copolymer [219]. A crosslinked latex with a three-dimensional network is achieved by polymerizing an ethylenically unsaturated monomer with a reactive saturated monomer using ether carboxylate as emulsifier [220]. 

Since the first preparation of stereoregular poly(methyl methacrylate) by Fox et al. and Miller et al. in 1958, a large number of papers have been published on the steieospecific polymerization of methyl methacrylate, while the NMR technique for the determination of microstructure developed by Bovey and Tiers and Nishioka et al. enabled us to accumulate the extensive information on this polymerization. Mostly anionic initiators have been used for the pdymerization. A review on the polymerization by lithium compounds was presented by Bywater In a recent review by Pino and Suter were discussed some of the factors which can influence the stereoregulation in the polymerization of vinyl monomers including a-substituted acrylate. A variety of magnesium and aluminum compounds can be utilized as stereospecific initiators. Besides methyl methacrylate, not only methacrylates with various ester groups, but also a-substituted acrylates, such as a-ethyl- or o-phenyl-acrylate, were also subjected to the stereospecific polymerization by anionic initiator. The stereospecificity in the copolymerization between the monomers described above is also a matter of interest. 

Methyl methacrylate polymerizations, initiated by oiganomagnesium compounds, also yield abnormal products. Here, the active centers are unusually persistent and stabile. In addition, the a-carbon atoms of the monomers were found to assume tetrahedral configurations.This suggests that the active centers contain covalent magnesium carbon bonds. Also, gel permeation chromatography curves of the products show that more than one active center operates independently. A pseudoanionic mechanism was therefore postulated for polymerizations of acrylic and methacrylic esters by Grignard reagents. 

The polymerization of acrylate esters by organomagnesium reagents is best described as pseudo-anionic monomer is complexed to a magnesium atom covalently bonded to carbon. The anionic polymerization of methyl methacrylate in benzene yields the syndiotactic polymer when the initiator is an alkali metal complexed with 18-dicyclohexyl-6-crown. When a solution of methyl methacrylate in toluene is placed below a solution of butyl-lithium in the same solvent at —78 °C so as to avoid any mechanical mixing, the polymer obtained has a higher isotacticity than that observed if the solutions are stirred. ... 

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