Authors: Zhenxi Wang Qinghua Zhang Xiaoli Zhan Fengqiu Chen Guohua Rao Jihai Xiong
Publish Date: 2013/10/14
Volume: 20, Issue: 11, Pages: 288-
Abstract
Welldefined PSbPS/Bd diblock copolymers were synthesized via reversible additionfragmentation chain transfer RAFT miniemulsion polymerization instead of anionic polymerization which was environmental friendly energy and cost saving for most monomers In order to precisely design styrene/butadiene block with targeted composition profile given the feeding program binary monomers RAFT miniemulsion polymerization kinetic models were formulated In butadiene RAFT seeded miniemulsion polymerization it was well performed and the RAFT equilibrium constant between butadiene and 1phenylethyl phenyldithioacetatePEPDTA was estimated to be 183 L/mol × s at 70 °C Furthermore the modeling curves could well predict styrene/butadiene RAFT miniemulsion polymerization kinetics including monomers conversion volume fraction of monomers numberaverage molecular weight and composition The copolymers were characterized by fourier translation infrared spectroscopyFTIR hydrogen nuclear magnetic resonance spectroscopy1HNMR transmission electron microscopyTEM and differential scanning calorimetryDSC FTIR and 1HNMR results indicated that the microstructure of the polymer was mainly 1 4trans butadiene with small amount of 1 2units Microphase morphologies of the copolymers were lamellar cylinder and disordered phase by TEM which was identical to selfconsistent field calculations And thermal property results showed that glass transition behaviors were corresponding with their microphase separation sequence length and composition from DSCThe authors gratefully thank the financial support from the National Natural Science Foundation of China 21276224 21176212 and 51303074 Program for Science and Technology Funds of Jiangxi Province 20123BBE50113 and 2008GQC0060 and the Research Funds of Jiangxi Academy of Sciences 2013XTPH113 2012–02 and 2011YYB06
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