Premium
Polymers from pine gum components: Radical and coordination homo and copolymerization of pinenes
Author(s) -
Ramos Ana Maria,
Lobo Luís S.,
Bordado João M.
Publication year - 1998
Publication title -
macromolecular symposia
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.257
H-Index - 76
eISSN - 1521-3900
pISSN - 1022-1360
DOI - 10.1002/masy.19981270109
Subject(s) - copolymer , styrene , polymer chemistry , pinene , methyl methacrylate , polymerization , polymer , reactivity (psychology) , radical polymerization , catalysis , chemistry , materials science , organic chemistry , medicine , alternative medicine , pathology
The present work is aimed at studying the reactivity of α‐ and β‐pinenes in radical polymerization. The pinene homopolymers obtained were oligomers, showing both isomers similar reactivities. In order to achieve products of higher molecular weight, the radical copolymerization of α‐ and β‐pinene with methyl methacrylate and styrene was performed, giving rise to polymers with M̄ w varying from 11 500 to 53 000. In radical copolymerization α‐pinene showed to be more reactive than β‐pinene. All the radical reactions performed were carried out with a Ziegler‐Natta catalyst, TiCl 4 /Et 3 Al, and with Et 3 Al. Under the conditions tested, β‐pinene did not undergo any polymerization reaction and the cocatalyst showed a pronounced catalytic effect. The coordination polymers obtained at 5 h had chain lenghts of the same order of magnitude of the corresponding radical copolymers obtained at 50 h, although for much lower overall conversion.