The Effect of Bulky Ester Alkyl Substituents on Rate Constants of Radical Polymerization of Dialkyl Fumarates

摘要

The radical polymerization of various dialkyl fumarates (DRF) was investigated kinetically, and the propagation and termination rate constants (k_p and k_t) were determined by ESR spectroscopy. It was revealed that the introduction of bulky ester group promoted the polymerization reactivity, i.e k_t values decreased as the steric effect of the alkyl substituents increased. However, the k_p values increased with increasing of the bulkiness of the alkyl substituents. These results were interpreted by the stereospecific propagation leading to the diisotactic polymer formation.