STUDIES ON THE DIFFUSION CONTROLLED KINETICS OF STYRENE ZIEGLER-NATTA POLYMERIZATION

The kinetics of styrene polymerization on TiCl3-Al(C2H5)3 catalysts in toluene, n-heptane or toluene-n-heptane mixtures were studied. A mathematical model of monomer diffusion controlled polymerization in globle polymer particles containing catalyst was designed, which explained quantitatively the decay of polymerization rate caused by diffusion barrier and the different rate decays in different mediums. The kinetic curves treated with the model show that polymerizations in good solvent for polystyrene are less diffusion controlled than in non-solvent, and the catalyst containing particles in good solvent systems are smaller than in the non-solvent systems.