Order-order transition induced by mesophase formation in a novel type of   diblock copolymers based on poly(isobutyl methacrylate) and poly[2,5-di(   isopropyloxycarbonyl)styrene]

doi:10.1039/b915519h

CORC > 北京大学 > 化学与分子工程学院

	Order-order transition induced by mesophase formation in a novel type of diblock copolymers based on poly(isobutyl methacrylate) and poly[2,5-di( isopropyloxycarbonyl)styrene]
	Guan, Yan ; Chen, Xiaofang ; Ma, Hongyang ; Shen, Zhihao ; Wan, Xinhua
刊名	软性材料
	2010
关键词	COIL BLOCK-COPOLYMERS LIQUID-CRYSTALLINE BLOCK UNUSUAL PHASE-BEHAVIOR SIDE-GROUP BLOCK ROD-COIL RADICAL POLYMERIZATION MICROPHASE SEPARATION GRAFT-COPOLYMERS VINYL-POLYMERS COMB-LIKE
DOI	10.1039/b915519h
英文摘要	Novel diblock copolymers based on poly(isobutyl methacrylate) (PiBMA) and poly[2,5-di(isopropyloxycarbonyl) styrene] (PiPCS) were designed and prepared via consecutive atom transfer radical polymerization. They had relatively low molecular weight distributions and tunable molecular weights. The molecular characterization of the copolymers was performed with proton nuclear magnetic resonance spectroscopy, gel permeation chromatography, and thermogravimetric analysis. The phase structures and transitions were investigated by differential scanning calorimetry, small- and wide-angle X-ray scattering, and polarized optical microscopy experiments. A PiPCS block with a polymerization degree higher than 168, exhibited a stable hexagonal columnar liquid crystalline (Colh LC) phase, regardless of the length of PiBMA block. The PiPCS block underwent a coil-to-rod conformational change when it transformed into Colh LC phase. For the PiBMA-b-PiPCS diblock copolymer, this conformational transition resulted in a topological change from a coil-coil to a rod-coil type structure. With increasing PiPCS fraction, the block copolymers' microphase separated structure changed from an undetermined phase, to a lamellar phase, to a PiBMA columnar phase in the coil-coil system. The original microphase separated structure observed with coil PiPCS block could evolve into a lamellar morphology, with a significantly increased long period when PiPCS transformed into Colh LC phase. Thereafter it served as a rod in the block copolymers studied. This microphase separated structure transition was triggered by the coil-to-rod (isotropic-to-LC) transition and was irreversible due to the fact that the LC phase of PiPCS block remained at higher temperatures until decomposition.; Chemistry, Physical; Materials Science, Multidisciplinary; Physics, Multidisciplinary; Polymer Science; SCI(E); EI; 7; ARTICLE; 5; 922-927; 6
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/151231]
专题	化学与分子工程学院
推荐引用方式 GB/T 7714	Guan, Yan,Chen, Xiaofang,Ma, Hongyang,et al. Order-order transition induced by mesophase formation in a novel type of diblock copolymers based on poly(isobutyl methacrylate) and poly[2,5-di( isopropyloxycarbonyl)styrene][J]. 软性材料,2010.
APA	Guan, Yan,Chen, Xiaofang,Ma, Hongyang,Shen, Zhihao,&Wan, Xinhua.(2010).Order-order transition induced by mesophase formation in a novel type of diblock copolymers based on poly(isobutyl methacrylate) and poly[2,5-di( isopropyloxycarbonyl)styrene].软性材料.
MLA	Guan, Yan,et al."Order-order transition induced by mesophase formation in a novel type of diblock copolymers based on poly(isobutyl methacrylate) and poly[2,5-di( isopropyloxycarbonyl)styrene]".软性材料 (2010).