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Synthesis and conversion of vinyl aminoethyl ethers—XIII. Copolymerization of some vinyl aminoethyl ethers with methyl methacrylate
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Abstracts
rates in the amorphous zones of the polymer differing from those in the crystalline zones. The degree of crystallinity of the specimens m a y be estimated from the linear anamorphoses of the kinetic curves. On the basis of the experimental and reported data on the rate constants the recombination mechanism of radicals in polymers has been discussed. The rate of recombination is apparently determined by the motion of the chain segments. The anomalously high values of the pre-exponential factors and the compensation effect in the recombination of alkyl radicals have been interpreted in terms of a fall in the segment rotation harrier on approaching the melting temperature.
POLYMERIZATION OF 2-ETHYLBUTADIENCE-1,3
I. A. L i f s h i t s a n d L. M. K o r o b o v a , V y s o k o m o l . s o e d i n . 3: No.
6, 8 9 1 - 8 9 7 , 1961.
THE lithium and organolithium induced polymerization of 2-ethylbutadiene-I,3 has been investigated. Elastomers have been obtained, the non-filler vulcanizates of which are endowed with high strength and elastic properties. I n the polymerization of 2-alkyl derivatives of 1,3-butadiene under the influence of butyllithium the number of units adding in the 3,4 position increases with increase of temperature from 0 ° to 100 °.
*NEW CATALYSTS FOR THE POLYMERIZATION OF ETHYLENE OXIDE
0 . V. K r y l o v a n d Y u . E. S i n y a k , V y s o k o m o l . s o e d i n . 3: No. 6, 8 9 8 - 9 0 0 , 1961. NEW catalysts belonging to the main subgroup of the second group of the Mendeleev System, namely Be(OH)2, Mg(OH)~, B e e have been found for the polymerization of ethylene oxide. The polymers obtained with these contacts are of a molecular weight up to 500,000. The most active of the catalysts is beryllium hydroxide. The molecular weight of the polymer was found to increase in the course of polymerization on Be(OH)~. The results obtained bear evidence of a stepwise mechanism of ethylene oxide polymerization. The catalytic activity of the compounds is a t t r i b u t e d by the authors to two centers on the surface, proton donors and proton accepters. Under such conditions propylene oxide afforded insignificant amounts of liquid and oily polymers.
SYNTHESIS AND CONVERSION OF VINYL AMINOETHYL E T H E R S - XIII. COPOLYMERIZATION OF SOME VINYL AMINOETHYL ETHERS W I T H METHYL METHACRYLATE
I. A. C h e k u l a e v a , M. F . S h o s t a k o v s k i i , V. A. G l a d y s h e v s k a y a a n d I. V. L i p o v i c h , V y s o k o m o l . s o e d i n . 3: No. 6, 9 0 1 - 9 0 7 , 1961. THE copolymerization of methylmethaerylate with vinyl-p-dimethylazninoethyl ether and its quaternary a m m o n i u m salts as well as of imino-bis-(vinylethyl ether) in the presence of azobisisobutyronitrile has been investigated. Benzoyl peroxide does not initiate the reaction. The copolymers have been prepared and the yield and composition have been correlated with the initial monomer ratios. The m a x i m u m incorporation of the vinyl ethers in the eopolymer does not exceed 50~o. The structure of the ethers determines their behaviour. On copolymerization of vinyl-fl-dimethylaminoethyl ether with large excess of methylmethaerylate polymethylmethacrylate forms in addition to the copolymers. The quarternary a m m o n i u m salts are less pronce to eopolymerization t h a n the respective free bases. The imino-bis-(vinylethyl ether) copolymer has a three-dimensional structure. The monomer ratios of methyl methaerylate and the various vinyl aminoethyl ethers have been determined.
Abstracts
rates in the amorphous zones of the polymer differing from those in the crystalline zones. The degree of crystallinity of the specimens m a y be estimated from the linear anamorphoses of the kinetic curves. On the basis of the experimental and reported data on the rate constants the recombination mechanism of radicals in polymers has been discussed. The rate of recombination is apparently determined by the motion of the chain segments. The anomalously high values of the pre-exponential factors and the compensation effect in the recombination of alkyl radicals have been interpreted in terms of a fall in the segment rotation harrier on approaching the melting temperature.
POLYMERIZATION OF 2-ETHYLBUTADIENCE-1,3
I. A. L i f s h i t s a n d L. M. K o r o b o v a , V y s o k o m o l . s o e d i n . 3: No.
6, 8 9 1 - 8 9 7 , 1961.
THE lithium and organolithium induced polymerization of 2-ethylbutadiene-I,3 has been investigated. Elastomers have been obtained, the non-filler vulcanizates of which are endowed with high strength and elastic properties. I n the polymerization of 2-alkyl derivatives of 1,3-butadiene under the influence of butyllithium the number of units adding in the 3,4 position increases with increase of temperature from 0 ° to 100 °.
*NEW CATALYSTS FOR THE POLYMERIZATION OF ETHYLENE OXIDE
0 . V. K r y l o v a n d Y u . E. S i n y a k , V y s o k o m o l . s o e d i n . 3: No. 6, 8 9 8 - 9 0 0 , 1961. NEW catalysts belonging to the main subgroup of the second group of the Mendeleev System, namely Be(OH)2, Mg(OH)~, B e e have been found for the polymerization of ethylene oxide. The polymers obtained with these contacts are of a molecular weight up to 500,000. The most active of the catalysts is beryllium hydroxide. The molecular weight of the polymer was found to increase in the course of polymerization on Be(OH)~. The results obtained bear evidence of a stepwise mechanism of ethylene oxide polymerization. The catalytic activity of the compounds is a t t r i b u t e d by the authors to two centers on the surface, proton donors and proton accepters. Under such conditions propylene oxide afforded insignificant amounts of liquid and oily polymers.
SYNTHESIS AND CONVERSION OF VINYL AMINOETHYL E T H E R S - XIII. COPOLYMERIZATION OF SOME VINYL AMINOETHYL ETHERS W I T H METHYL METHACRYLATE
I. A. C h e k u l a e v a , M. F . S h o s t a k o v s k i i , V. A. G l a d y s h e v s k a y a a n d I. V. L i p o v i c h , V y s o k o m o l . s o e d i n . 3: No. 6, 9 0 1 - 9 0 7 , 1961. THE copolymerization of methylmethaerylate with vinyl-p-dimethylazninoethyl ether and its quaternary a m m o n i u m salts as well as of imino-bis-(vinylethyl ether) in the presence of azobisisobutyronitrile has been investigated. Benzoyl peroxide does not initiate the reaction. The copolymers have been prepared and the yield and composition have been correlated with the initial monomer ratios. The m a x i m u m incorporation of the vinyl ethers in the eopolymer does not exceed 50~o. The structure of the ethers determines their behaviour. On copolymerization of vinyl-fl-dimethylaminoethyl ether with large excess of methylmethaerylate polymethylmethacrylate forms in addition to the copolymers. The quarternary a m m o n i u m salts are less pronce to eopolymerization t h a n the respective free bases. The imino-bis-(vinylethyl ether) copolymer has a three-dimensional structure. The monomer ratios of methyl methaerylate and the various vinyl aminoethyl ethers have been determined.