The architecture of hydroxy-functionalized aPS-b-random copolymer-b-PE via one-pot strategy combining living free radical polymerization with coordination polymerization

The copolymerization of styrene with ethyl- ene was promoted by CpTiCl3/BDGE/Zn/MAO catalyst system combining free radical polymerization with coordi- nation polymerization via sequential monomer addition strategy in one-pot. The effect of polymerization condi- tions such as temperature, time, ethylene pressure, and Al/Ti molar ratio on the polymerization performance was investigated. The hydroxy-functionalized aPS-b-random copolymer-b-PE triblock copolymer was obtained by sol- vent extraction and determined by GPC, DSC, WAXD, and 13 C-NMR. The DSC result indicated that the aPS-b- random copolymer-b-PE had a Tg at 87 � C and a Tm at 119 � C which attributed to the Tg of aPS segment and the Tm of PE segment, respectively. The microstructure of the hydroxy-functionalized aPS-b-random copolymer-b-PE was further confirmed by WAXD, 13 C-NMR, and 1 H-NMR analysis; and these results demonstrated that the obtained block copolymer consisted of aPS segment, S-E random co- polymer segment, and crystalline PE segment. The connec- tion polymerization of the hydroxy-functionalized aPS with random copolymer-b-PE was revealed by GPC results. V C 2011 Wiley Periodicals, Inc. J Appl Polym Sci 120: 3171-3179, 2011