Kinetics and mechanism of the phenylacetylene metathesis polymerization catalyzed with WOCl4/Ph4Sn in benzene

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Title:Kinetics and mechanism of the phenylacetylene metathesis polymerization catalyzed with WOCl4/Ph4Sn in benzene
Creators:
Vohlídal, Jiří
Holländer, Andreas
Jančálková, Markéta
Sedláček, Jan
Sargánková, Irena
Journal or Publication Title:
Collection of Czechoslovak Chemical Communications, 56, 2, pp. 351-367

Abstract

Tungsten oxychloride alone and in combination with Ph<sub>4</sub>Sn were found to induce a polymerization of phenylacetylene (PhA) to<i>trans</i>-rich poly(phenylacetylene) (PPhA). The binary catalyst has a narrow maximum of the activity at the molar ratio [Ph<sub>4</sub>Sn]<sub>o</sub> =<i>y</i> = 2, so that two molecules of Ph<sub>4</sub>Sn are necessary for a conversion of one molecule of WOCl<sub>4</sub> to the most active precursor specie. An identical excess of Ph<sub>4</sub>Sn acts as a noncompetitive inhibitor (retarder) of the overall polymerization. The order of reaction with respect to catalyst (for <i>y</i> = 2) varies with a concentration of the catalyst. It has value 1 for [WOCl<sub>4</sub>]<sub>o</sub> from 0.1 to ca 4 mmol.dm<sup>-3</sup> and gradually increases over this concentration limit. Mutual interactions of partially associated growing species, eliminating inhibitive effects of monomer and organotin compounds, are supposed as a reason of this uncommon behaviour. The self inhibitive effect of polymerizing PhA was deduced from the dependence of the initial rate of polymerization on the concentration of PhA. This inhibition takes part most probably in both, the initiation and the propagation. The attempts to determine molecular weights of PPhA by VPO method failed because of a rapid degradation of polymer in diluted solution exposed to atmospheric oxygen.

Title:Kinetics and mechanism of the phenylacetylene metathesis polymerization catalyzed with WOCl4/Ph4Sn in benzene
Creators:
Vohlídal, Jiří
Holländer, Andreas
Jančálková, Markéta
Sedláček, Jan
Sargánková, Irena
Divisions:Life and Chemical Sciences > Institute of Organic Chemistry and Biochemistry > Collection of Czechoslovak Chemical Communications
Journal or Publication Title:Collection of Czechoslovak Chemical Communications
Volume:56
Number:2
Page Range:pp. 351-367
ISSN:0010-0765
E-ISSN:1212-6950
Publisher:Institute of Organic Chemistry and Biochemistry
Related URLs:
URLURL Type
http://dx.doi.org/10.1135/cccc19910351UNSPECIFIED
ID Code:4955
Item Type:Article
Deposited On:22 Feb 2010 11:27
Last Modified:22 Feb 2010 10:27

Citation

Vohlídal, Jiří; Holländer, Andreas; Jančálková, Markéta; Sedláček, Jan; Sargánková, Irena (1991) Kinetics and mechanism of the phenylacetylene metathesis polymerization catalyzed with WOCl4/Ph4Sn in benzene. Collection of Czechoslovak Chemical Communications, 56 (2). pp. 351-367. ISSN 0010-0765

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