화학공학소재연구정보센터
Industrial & Engineering Chemistry Research, Vol.47, No.15, 5734-5741, 2008
Polymerization of N-vinylcarbazole in supercritical carbon dioxide and in a supercritical region of a carbon dioxide and dimethyl ether mixture
Spherical poly(N-vinylcarbazole) (PVK) particles were synthesized by polymerization of N-vinylcarbazole (NVCA) in supercritical carbon dioxide (ScCO2) and a supercritical region of a CO2 and dimethyl ether (DME) mixture using a fluorine-based [poly(3,3,4,4,5,5,6,6,7,7,8,8,9,9,10,10,10-heptadecafluorodecyl methacrylate)] [poly(HDFDMA)] polymer as the surfactant and 2,2'-azobisisobutyronitrile (AIBN) as the initiator. The spherical PVK particles could be consistently produced under the given experimental conditions. The PVK particle size showed a bimodal distribution when ScCO2 was used as solvent. Therefore DME was added to the system as a cosolvent. The resulting particle size was shown to be dependent on the amount of surfactant and DME added to the system. As the ratio of DME increased, the average molecular mass of the PVK particles decreased. The effects of surfactant and initiator concentrations were investigated with respect to the morphology, size, and molecular mass of the PVK particles. The effects of the addition of a mixed solvent consisting of CO2 + DME on polymeric particle morphology, size, and molecular mass of polymers were also studied and are discussed herein.