KINETIC INVESTIGATION OF THE FREE-RADICAL CROSS-LINKING COPOLYMERIZATION OF STYRENE WITH A MIXTURE OF DIVINYLBENZENE ISOMERS ACTING AS THE CROSS-LINKER

The objective of this paper is to study the crosslinking copolymerizat ion of styrene (S) with a mixture of para- and meta-divinylbenzenes (m ixed-DVBs). The crosslinking copolymerization, initiated with benzoyl peroxide (BPO), was performed at temperatures of 70, 80, and 90 degree s C. The mole ratio of DVB to S was kept small, i.e. within 4-8%. At v arious stages of the polymerization the overall conversion of the mono mers to sol and gel were measured by gravimetry. The sol and gel forma tions with time were also measured. The gels were characterized by equ ilibrium swelling measurements as a function of the overall degree of conversion. The experimental data were then incorporated into the kine tic model developed by Tobita and Hamielec. The kinetic parameters inv olved in the crosslinking copolymerization of S/DVB were also estimate d. A satisfactory agreement of the results obtained from the experimen tal measurements with the predictions of the model was observed. Copyr ight (C) 1996 Elsevier Science Ltd.