Influence of the content of n-butanol on the critical conversion of gel formation during “living” three-dimensional radical co-polymerization of styrene and divinylbenzene

Abstract

In this work, a study was made of the copolymerization of styrene and divinylbenzene in the presence of alkoxyamine synthesized “in situ” from benzoyl peroxide and 2,2,6,6-tetramethylpiperidine-1-oxyl in a solution of n-butanol (50-70 wt.%) at 120 °C. According to the experimental data obtained, the critical gelation conversion lies in the range of 50-75%. A decrease in the critical gelation conversion is also observed when the content of n-butanol 60%, which is accompanied by a separation of the system into two phases, that is, polymer is precipitated. With a lower content of precipitator, the separation of the system into two phases does not occur. It is assumed that in this case the removal of highly branched macromolecules from the polymerizing system occurs as a result of occlusion of “suspended” double bonds that become inaccessible to radicals, but “suspended” double bonds of linear and weakly branched macromolecules remain available for participation in the reaction with growth radicals.