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The specific features of free-radical polymerization of methyl methacrylate in the presence of a new initiating system, benzoyl peroxide-N,N-dimethyl-N-(methylferrocenyl)amine, are studied. Mutual influence of the ferrocene and amino groups on the kinetic parameters of polymerization and on the microstructure of the resulting polymers is revealed. The polymer formed in the presence of this initiating system is shown to have a predominantly syndiotactic structure.  相似文献   
3.
The effect of ferrocene and zirconocene dichloride on the rate and constants of copolymerization of methyl methacrylate with styrene was studied. The results obtained suggest that the metallocenes in the elementary steps of the reaction.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 2, 2005, pp. 297–300.Original Russian Text Copyright © 2005 by Yumagulova, Kolesov, Monakov.  相似文献   
4.
The radical copolymerization of N,N-diallyl-N,N-dimethylammonium chloride (AMAC) (M1) with ethylene glycol vinyl ether (M2) in an aqueous medium proceeds at a high rate to afford random copolymers. The reactivity ratios equal to r 1 = 2.18 and r 2 = 0.01 indicate that AMAC is a more active comonomer. The overall reaction order in comonomers is 2.4, and the effective activation energy is 97.4 ± 2 kJ/mol. The monomer M1 enters into copolymerization by both of the double bonds with the formation of pyrrolidinium structures in the chain through the cyclization stage.  相似文献   
5.
The effect of zirconocene dichloride and its indene-containing derivative on the radical polymerization of methyl methacrylate initiated by benzoyl peroxide has been studied. The influence of the metallocenes on the kinetic parameters of the process and the average degree of polymerization has been established. Concentration and temperature dependences have been measured for the initial rate of reaction and the average degree of polymerization in relation to the content of the components in the systems. The microstructure of poly(methylmethacrylate) prepared in the presence of the used initiation systems has been determined.  相似文献   
6.
Radical copolymerization of N,N-diallyl-N′-benzoylhydrazine with acrylonitrile and sulfur dioxide was studied. The kinetic features of the copolymerization of these systems were examined, the relative activities of the monomers were determined, and the structure of the resulting copolymers was elucidated.  相似文献   
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The stereoregulating heterogeneity manifested in butadiene polymerization by active sites of the titanium catalytic system formed “separately” in combination with organoaluminum ligands was examined.  相似文献   
9.
The cationic polymerization of 1,3-pentadiene in the presence of vanadium oxytrichloride is studied. 1,3-Pentadiene is shown to polymerize at a high rate to high monomer conversions in the absence of proton-donor compounds in the catalytic system. The initial rate of 1,3-pentadiene polymerization is proportional to the concentration of VOCl3 in the system and demonstrates an extremal dependence on the initial concentration of 1,3-pentadiene. The polymerization process is distinguished by an induction period whose duration increases with a decrease in the reaction temperature. Regardless of polymerization conditions, with an increase in the monomer conversion, the molecular-mass distribution of the polymer widens owing to formation of a high-molecular-mass fraction, which, depending on reaction conditions, can be consumed in formation of the gel fraction. It is shown that the degree of unsaturation and the microstructure of poly(1,3-pentadiene) are almost independent of the polymerization conditions.  相似文献   
10.
Russian Journal of Applied Chemistry - Interaction of oxidized arabinogalactan of Siberian larch (Larix Sibirica L.) with Kanamycin antibiotic in aqueous solutions was studied by physicochemical...  相似文献   
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