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Indexed by:期刊论文

Date of Publication:2007-05-01

Journal:EUROPEAN POLYMER JOURNAL

Included Journals:SCIE、EI、Scopus

Volume:43

Issue:5

Page Number:1969-1977

ISSN No.:0014-3057

Key Words:chain extension; copolyesters; liquid crystalline; degradation

Abstract:To increase the molecular weights of the synthesized liquid crystalline aromatic/aliphatic copolyesters and to avoid crosslinking, a solution polymerization of the prepolymer and chain extender hexamethylene diisocyanate was adopted. The effects of chain extension on polyester molecular weights, thermal and mechanical properties, and biodegradable behaviors were investigated respectively. The catalysis mechanism and the copolyesters morphological textures were also investigated. The synthesized copolyesters were characterized by means of Fourier transform infrared spectra (FTIR), gel permeation chromatography (GPC), viscosity measurements, differential scanning calorimetry (DSC), X-ray diffraction (XRD),. polarizing light microscopy (PLM), scanning electron microscopy (SEM) and mechanical property measurements. It was found that inherent viscosities and the molecular weights of the copolyesters were remarkably increased under the action of catalyst, leading to a increase in the tensile strength. The degree of relative crystallinity, the melting temperature, and the rate of degradation decreased after chain extension. (C) 2007 Elsevier Ltd. All rights reserved.