Solution polymerization behavior of N-vinylcarbazole by low-temperature azoinitiator

Abstract

N-Vinylcarbazole (VCZ) was solution polymerized in 1,1,2,2,-tetrachloro-ethane (TCE) at 30, 40, and 50 degrees C using a low-temperature initiator, 2,2'-azobis(2,4-dimethylvaleronitrile) (ADMVN); the effects of polymerization temperature and concentrations of initiator and solvent were investigated. On the whole, the experimental results corresponded to predicted ones. Low-polymerization temperature using ADMVN proved to be successful in obtaining poly(N-vinylcarbazole) (PVCZ) of high molecular weight with smaller temperature rise during polymerization, nevertheless of free radical polymerization by azoinitiator. The polymerization rate of VCZ in TCE was proportional to the 0.46 power of ADMVN concentration. The molecular weight was higher and the molecular weight distribution was narrower with PVCZ polymerized at lower temperatures. For PVCZ produced in TCE at 30 degrees C using ADMVN concentration of 0.00005 mol/mol of VCZ, weight-average molecular weight of 271 000 was obtained, with polydispersity index of 1.66. (C) 2000 John Wiley & Sons, Inc.