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Indexed by:期刊论文

Date of Publication:2014-05-27

Journal:POLYMER

Included Journals:SCIE、EI、Scopus

Volume:55

Issue:11

Page Number:2751-2760

ISSN No.:0032-3861

Key Words:Iodinated poly(ester-urethane)s; Retarded crystallization; Dual recrystallization

Abstract:A series of biodegradable radiopaque iodinated poly(ester-urethane)s (IPEUs) were synthesized by chain-extension of dihydroxylated poly(butylene succinate) (PBS OH) and isophorone diisocyanate (IPDI) with iodinated bisphenol-A (IBPA). The effects of IBPA on the crystallization and melting behaviour of IPEUs were investigated by wide-angle X-ray diffraction (WAXD), polarized optical microscope (POM), differential scanning calorimetry (DSC), and temperature-modulated differential scanning calorimetry (TMDSC). WAXD results suggest that the PBS soft segments form only one crystal modification, and that the crystallinity of the samples decreases with increasing the amorphous hard segments. POM observation indicates that the ring-bands of spherulites disappear and then the spherulitic texture is disturbed with increasing the IBPA content. The analysis of isothermal crystallization kinetics shows that the crystallization of IPEUs is retarded by the introduction of IBPA chain extender with bulky pendent groups. In the DSC heating curves, at most four endothermic peaks were observed and their origins were examined. Two recrystallization exothermic peaks were observed for IPEUs in the nonreversible signals of TMDSC. The twice sequential melting-recrystallization-remelting model could be used to explain the multiple melting behaviour of IPEUs. (C) 2014 Elsevier Ltd. All rights reserved.