Synthesis and Properties of Multibranched and Cylindrical Polymers via Living Radical Polymerization of Miner

点击翻译按钮获取中文摘要

The aim of this project is to study the architecture and properties of hyperbranched macromolecules and nanocylinders via living radical mechanism. The results obtained as follows.1. Hyperbranched poly (ethyl methacrylate)s (PEMA) were prepared by living radical copolymerization of 2-(N,N-diethyldithiocarbamyl)ethyI methacrylate (inimer : DTEM) with EMA under UV irradiation. Two monomers showed the almost equal reactivity toward both propagating species, and the copolymer composition was the same as the comonomer feed. This result means that both the branching and chain length of the hyperbranched molecules can be controlled statistically by the feed monomer ratios.2. We studied the living nature on the formation of hyperbranched PEMA in benzene. We performed the first-order time-conversion plots in this polymerization system, and the straight line in the semilogarithmic coordinates indicated first order in monomer. It was concluded that free radical polymerization proceeded with living radical mechanism. We treated the kinetics on initiation and propagation steps using model compounds. As a result, the degree of branching was estimated to be 0.5 using such rate constants.3. Polystyrene having pendant carbamate (DC) groups was prepared by (N,N-diethyldithiocarbamyl)-methylstyrene (DTCS). Subsequently, photograft-polymerization of DTCS on such functionalized PS was carried out under UV irradiation. This product exhibited hyperbranched structure at the side group. As the main chain was stretched and behaived as nanocylinder in solution.