Spectroscopic investigation of the polymorphism and side group location   of ethylene copolymers

doi:10.1021/ma0358576

CORC > 北京大学 > 化学与分子工程学院

	Spectroscopic investigation of the polymorphism and side group location of ethylene copolymers
	Su, ZQ ; Zhao, Y ; Xu, YH ; Zhang, XQ ; Zhu, SN ; Wang, DJ ; Wu, JG ; Han, CC ; Xu, DF
刊名	macromolecules
	2004
关键词	C-13 NMR-SPECTROSCOPY X-RAY-DIFFRACTION VINYL ACETATE COPOLYMERS PHASE-STRUCTURE CRYSTALLIZATION CONDITIONS NONLINEAR POLYETHYLENE ALCOHOL COPOLYMERS GLASSY POLYMERS TEMPERATURE POLYPROPYLENE
DOI	10.1021/ma0358576
英文摘要	The polymorphism and side group location of a series of ethylene-vinyl acetate copolymers (EVA) and their hydrolytic products (EVOH) have been investigated by high-resolution cryogenic Fourier transform infrared (FTIR) and nuclear magnetic resonance (NMR) spectroscopy. The experimental results indicated that FTIR spectra can provide direct evidence for side groups entering the crystal lattice of ethylene segments. Through the characterization of the specific IR band variation, it was proved that the hydroxyl group of EVOH enters the crystal lattice, while the side groups of EVA exist predominantly in the amorphous region. The polymorphism and the crystalline phase transformation were investigated for the two series of ethylene copolymers. It was proved that there is only an orthorhombic crystalline phase for all the EVOH copolymers. For EVA copolymers, however, besides the occurrence of a normal orthorhombic crystalline phase, a monoclinic crystalline phase was also detected for the samples with a relatively high content of side groups. The monoclinic crystalline phase is a substable structure and is mainly affected by the content of the side groups and the crystallization conditions. The content of monoclinic crystals does not increase linearly with branching, but to some extent, the increase of the side group content is propitious to the formation of a monoclinic crystalline state. Different heat-treatment methods have great influence on the polymorphism of EVA copolymers. With the increase of the annealing temperature, the monoclinic crystal was gradually transformed to an orthorhombic crystal.; Polymer Science; SCI(E); EI; 11; ARTICLE; 9; 3249-3256; 37
语种	英语
内容类型	期刊论文
源URL	[http://ir.pku.edu.cn/handle/20.500.11897/255042]
专题	化学与分子工程学院
推荐引用方式 GB/T 7714	Su, ZQ,Zhao, Y,Xu, YH,et al. Spectroscopic investigation of the polymorphism and side group location of ethylene copolymers[J]. macromolecules,2004.
APA	Su, ZQ.,Zhao, Y.,Xu, YH.,Zhang, XQ.,Zhu, SN.,...&Xu, DF.(2004).Spectroscopic investigation of the polymorphism and side group location of ethylene copolymers.macromolecules.
MLA	Su, ZQ,et al."Spectroscopic investigation of the polymorphism and side group location of ethylene copolymers".macromolecules (2004).