Monomer functionality and polymer network formation

In free radical polymerizations multivinyl monomers are used to create cros s-linked polymeric materials. By utilizing a kinetic model, the: relative e ffectiveness of divinyl and trivinyl crosslinking agents was investigated i n copolymerizations with monovinyl monomers where the cross-linking potenti al was equivalent. The trivinyl cross-linking agent was found to yield more cross-links and less cycles than the divinyl cross-linking agent. Interest ingly, prior to complete reaction, increased crosslinking as a function of conversion is also observed when no cyclization occurs. Here, the trivinyl crosslinking agent produced more elastically active cross-links than the di vinyl cross-linking agent as a function of conversion until 100%-conversion when the number of cross-links is the same, because cyclization is not pre sent. Differences between divinyl and trivinyl cross-linkers are also obser ved experimentally in the reaction kinetics of these copolymerizations. Wit h equal cross-linking potential, the trivinyl copolymerization reacted more rapidly than the divinyl copolymerization because the increased crosslinki ng led to more dramatic autoacceleration.