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A contribution to the study of the catalytic action of clays on the polymerization of styrene: II. Reaction mechanism

Published online by Cambridge University Press:  09 July 2018

D. Njopwouo
Affiliation:
Laboratoire de Chimie Miner ale Appliquee, Faculte des Sciences, B.P. 812 Yaounde, Cameroun
G. Roques
Affiliation:
Laboratoire de Ckimie Physique Macromoleculaire, ENSIC, 1 me Grandville, 54042 Nancy, France
R. Wandji
Affiliation:
Laboratoire de Chimie Miner ale Appliquee, Faculte des Sciences, B.P. 812 Yaounde, Cameroun

Abstract

The study of 13C NMR spectra of polystyrene thermally obtained on clays shows that thermal polymerization of styrene on these minerals proceeds by two parallel reaction mechanisms: the radical mechanism due to the thermal effect, and the cationic mechanism in which the initiatory cation H+ is provided by the clay. The latter mechanism, accelerated by increase in temperature, becomes more important as the clay content increases in the reaction medium. Otherwise, the thermal polymerization on clays is accompanied by the hydrogenation of some α carbons of the polystyrene molecule and the oxidation of certain aromatic carbons.

Type
Research Article
Copyright
Copyright © The Mineralogical Society of Great Britain and Ireland 1988

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