Synthesis of a Novel Hybrid Liquid-Crystalline Rod–Coil Diblock Copolymer
نویسندگان
چکیده
A series of novel rod–coil diblock copolymers on the basis of mesogenjacketed liquid-crystalline polymer were successfully prepared by atom transfer radical polymerization from the flexible polydimethylsiloxane (PDMS) macroinitiator. The hybrid diblock copolymers, poly{2,5-bis[(4-methoxyphenyl)oxycarbonyl]styrene}-blockpolydimethylsiloxane, had number-average molecular weights (Mn’s) ranging from 9500 to 30,900 and relatively narrow polydispersities ( 1.34). The polymerization proceeded with first-order kinetics. Data from differential scanning calorimetry validated the microphase separation of the diblock copolymers. All block copolymers exhibited thermotropic liquid-crystalline behavior except for the one with Mn being 9500. Four liquid-crystalline diblock copolymers with PDMS weight fractions of more than 18% had two distinctive glass-transition temperatures. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1799–1806, 2003
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