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Protonic and aprotonic mechanisms of polymerization initiated by potassium amide in liquid ammonia solution
Abstracts
361
with rise in fibre content. Time-deformation curves have been obtained for various temperatares and the activation energy of deformation ha~ been estimated. The latter was found to have a vMue of ca. 125 keal/mole for pure polystyrene and ca. 80 keal/mole for the filled polymer. The results obtained are explained on the assumption that the properties of a filled thermoplastic polymer are determined by the interaction of the secondary polymer structures (molecular packets) with the filler surface and by the structure of the packets themselves that are on the surface. PROTONIC A N D APROTONIC MECHANISMS OF P O L Y M E R I Z A T I O N P O T A S S I U M A M I D E IN L I Q U I D A M M O N I A SOLUTION
A. ]
~h~tenshtem,
E . A. Y ~ k o v l e v a , E. A. K o v r i z h n v k h ,
~md N . A. P r ~ v i k o w ,
V y s o k o m o l . s o e d i n . 4: N o .
INITIATED
BY
P. N . M a n o c h k i n ~
l, 4'2-51, 1962.
l'r has been fbund that low molecular weight polymers are fbrmed when a solution of K N H 2 in li~tuid anamonia acts upon ~-lncthylstyrene and on some dienes. The low polymerization rate permits use of deutero-exehange with K N H 2 in deuterated ammonia solution to estimate (he mobility of the hydrogen atoms in the monomers. The polymerization reactions of styrene and ~-methylstyrene in armnorua solutions of potassium amide have been compared and the propert.ies (molecular weight, nitrogen content, bromine numbers) of the polymers and of their fractions have been investigated. I t has been shown that in contrast to polymerization of styrene, proceeding according to the aprotonie mechanism (i.e. as the result of addition of the NH~ ion to the double bond)the main role in the polymerization of e-methylstyrene is played by processes associated with transition of a proton of the monomer molecule, of which the sMe chain hydrogen is characterized by its mobility. Modifications have been made in the extractive method of' fraetionating low molecular weight polymers. V U L C A N I Z A T I O N IN T H E PRESENCE OF D I P H E N Y L G U A N I D I N E - - I I . T H E R M A L D E G R A D A T I O N OF D I P H E N Y L G U A N I D I N E A N D ITS REACTION W I T H S U L P H U R AT T H E VULCANIZATION TEMPERATURE
B. A. D o g a d k i n a n d N. N. P a v l o v , V y s o k o m o l . so ed i n . 4: N o .
I, 5 2 - 5 7 ,
1962.
DIPHENYLGUANll)INE decomposes at vulcanization temperatures both in the melt. or in
solvenl medium with the formation of ammonia, aniline, tetraphenylmelamine and triphenyldiearbamide. The presence of a solvent with different dipole moment value does not affect the rate of ammonia formation. The reaction of the accelerator with sulphur is accompanied b y the fonnation of hy¢h'ogen sulphide and a complex mixture eont.ainin~ polysulphides of the type [{ -- S.r -- it. Diphenylguanidine does not react with rubber and the presence of rubber in the solution has no effect on the nature of the degradation process of" i he accelerator. P H O S P H O R U S - C O N T A I N I N G POLYMERS -- XXVII. H E T E R O C H A I N V I N Y L P H O S P H I N I C ACID A N D SOME D I H Y D R O X Y COMPOUNDS
POLYESTERS
OF
V. V. K o r s h ~ k , I. A. ( I r i b o v a , M. A. A n d r e y e v a . a n d (;. 3.l. P o p o v a , V y s o k o m o l . s o e d i n . 4: N o . l, 5 8 - 6 3 ,
1962.
THI.; possibility has been investigated of synthesizing hcteroclmin polyesters of vinylphosphinie aeM by the polyeondensation of vinylphosphinyl dichloride with diethyleneglycol The Publisher will be pleased to quote for the ~upply of a full English translation of any paper abstracted in these pages.
361
with rise in fibre content. Time-deformation curves have been obtained for various temperatares and the activation energy of deformation ha~ been estimated. The latter was found to have a vMue of ca. 125 keal/mole for pure polystyrene and ca. 80 keal/mole for the filled polymer. The results obtained are explained on the assumption that the properties of a filled thermoplastic polymer are determined by the interaction of the secondary polymer structures (molecular packets) with the filler surface and by the structure of the packets themselves that are on the surface. PROTONIC A N D APROTONIC MECHANISMS OF P O L Y M E R I Z A T I O N P O T A S S I U M A M I D E IN L I Q U I D A M M O N I A SOLUTION
A. ]
~h~tenshtem,
E . A. Y ~ k o v l e v a , E. A. K o v r i z h n v k h ,
~md N . A. P r ~ v i k o w ,
V y s o k o m o l . s o e d i n . 4: N o .
INITIATED
BY
P. N . M a n o c h k i n ~
l, 4'2-51, 1962.
l'r has been fbund that low molecular weight polymers are fbrmed when a solution of K N H 2 in li~tuid anamonia acts upon ~-lncthylstyrene and on some dienes. The low polymerization rate permits use of deutero-exehange with K N H 2 in deuterated ammonia solution to estimate (he mobility of the hydrogen atoms in the monomers. The polymerization reactions of styrene and ~-methylstyrene in armnorua solutions of potassium amide have been compared and the propert.ies (molecular weight, nitrogen content, bromine numbers) of the polymers and of their fractions have been investigated. I t has been shown that in contrast to polymerization of styrene, proceeding according to the aprotonie mechanism (i.e. as the result of addition of the NH~ ion to the double bond)the main role in the polymerization of e-methylstyrene is played by processes associated with transition of a proton of the monomer molecule, of which the sMe chain hydrogen is characterized by its mobility. Modifications have been made in the extractive method of' fraetionating low molecular weight polymers. V U L C A N I Z A T I O N IN T H E PRESENCE OF D I P H E N Y L G U A N I D I N E - - I I . T H E R M A L D E G R A D A T I O N OF D I P H E N Y L G U A N I D I N E A N D ITS REACTION W I T H S U L P H U R AT T H E VULCANIZATION TEMPERATURE
B. A. D o g a d k i n a n d N. N. P a v l o v , V y s o k o m o l . so ed i n . 4: N o .
I, 5 2 - 5 7 ,
1962.
DIPHENYLGUANll)INE decomposes at vulcanization temperatures both in the melt. or in
solvenl medium with the formation of ammonia, aniline, tetraphenylmelamine and triphenyldiearbamide. The presence of a solvent with different dipole moment value does not affect the rate of ammonia formation. The reaction of the accelerator with sulphur is accompanied b y the fonnation of hy¢h'ogen sulphide and a complex mixture eont.ainin~ polysulphides of the type [{ -- S.r -- it. Diphenylguanidine does not react with rubber and the presence of rubber in the solution has no effect on the nature of the degradation process of" i he accelerator. P H O S P H O R U S - C O N T A I N I N G POLYMERS -- XXVII. H E T E R O C H A I N V I N Y L P H O S P H I N I C ACID A N D SOME D I H Y D R O X Y COMPOUNDS
POLYESTERS
OF
V. V. K o r s h ~ k , I. A. ( I r i b o v a , M. A. A n d r e y e v a . a n d (;. 3.l. P o p o v a , V y s o k o m o l . s o e d i n . 4: N o . l, 5 8 - 6 3 ,
1962.
THI.; possibility has been investigated of synthesizing hcteroclmin polyesters of vinylphosphinie aeM by the polyeondensation of vinylphosphinyl dichloride with diethyleneglycol The Publisher will be pleased to quote for the ~upply of a full English translation of any paper abstracted in these pages.