Abstract: | An interesting effect of pyridine on the anionic polymerization of styrene in THF is described. Pyridine forms a complex with living polystyrene and greatly slows the polymerization rate without changing the degree of polymerization. From kinetic and spectroscopic studies, it was clear that there exist two active species in this system and the complex between living polystyrene and pyridine was of the 1:1 type, which itself had a weak ability to grow. The formation constant of the complex K was found to be about 4 × 105 l./mole. The effect of substituted pyridine was also studied and the nature of the complex was discussed. |