| dc.description.abstract | The copolymerization of styrene with cyclohexene, 1-methyl-1-cyclohexene,
and norbornene using ethenylbisindenylzirconium dichloride and methylaluminoxane,
Et(Ind)2ZrCl2-MAO, initiating systems has been tested. The results
obtained with each styrene-cycloalkene couple, except styrene/norbornene, indicate
a less effective polymerization process compared to styrene homopolymerization, in
agreement with the electronic and steric effects present in each comonomer. The
electronic I? effects of substituent groups, depending on their placement, largely
improve the polymerization process, while bulky groups on or near the vinyl carbon
double bond of styrene decrease its effectiveness. The present study shows that the
copolymers obtained are amorphous and their composition showed a lower abundance
of comonomer units with respect to the initial feed. For comparison, the
results of the copolymerization of styrene/(1-octadecene) using the same initiator
system and polymerization process are included, a polymerization that indicates a
more reactive process, and as the proportion of octadecene in the initial feed
increases, it showed a crystalline fusion temperature as well as a Tg in the styrene region which can be attributed to the formation of block styrene/octadecene
copolymers. | |
