Polymer, Vol.37, No.18, 4141-4148, 1996
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 copolymerization of styrene (S) with a mixture of para- and meta-divinylbenzenes (mixed-DVBs). The crosslinking copolymerization, initiated with benzoyl peroxide (BPO), was performed at temperatures of 70, 80, and 90 degrees C. The mole ratio of DVB to S was kept small, i.e. within 4-8%. At various stages of the polymerization the overall conversion of the monomers to sol and gel were measured by gravimetry. The sol and gel formations with time were also measured. The gels were characterized by equilibrium swelling measurements as a function of the overall degree of conversion. The experimental data were then incorporated into the kinetic model developed by Tobita and Hamielec. The kinetic parameters involved in the crosslinking copolymerization of S/DVB were also estimated. A satisfactory agreement of the results obtained from the experimental measurements with the predictions of the model was observed.
Keywords:CONTROLLED VINYL POLYMERIZATION;CROSS-LINKING COPOLYMERIZATION;RANDOM MACROMOLECULAR NETWORKS;PRE-GEL STATE;CHAINWISE POLYMERIZATION;POLYFUNCTIONAL MONOMERS;SYSTEMS;DIMETHACRYLATE;DERIVATION;STATISTICS