Reversible Transformation between Amorphous and Crystalline States of Unsaturated Polyesters by Cis-Trans Isomerization
发表时间:2019-11-01
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- 论文类型:
- 期刊论文
- 第一作者:
- Wan Zhao-Qian
- 合写作者:
- Ren Wei-Min,Yang Shuai,Li Ming-Ran,Gu Ge-Ge,Lu Xiao-Bing
- 发表时间:
- 2019-10-08
- 发表刊物:
- Angewandte Chemie (International ed. in English)
- 收录刊物:
- PubMed
- 文献类型:
- J
- ISSN号:
- 1521-3773
- 关键字:
- copolymerization,crystallinity,isomerization,smart materials,unsaturated polyesters
- 摘要:
- An aliphatic polyester has been prepared from ethylene oxide and maleic anhydride that undergoes reversible transformation between amorphous (Tg =18 °C) and crystalline (Tm =124 °C) states through cis-trans isomerization of the C=C bonds in the polymer backbone without any change in either the molecular weight or dispersity of the polymer. A similar transformation was also observed in chiral unsaturated polyesters formed from enantiopure terminal epoxides, such as epichlorohydrin, phenyl glycidyl ether, and (2,3-epoxypropyl)benzene. These unsaturated polyesters with 100 % E-configuration in the crystalline state were prepared by quantitative isomerization of their Z-configuration analogues in the presence of a catalytic amount of diethylamine, while in the presence of benzophenone, irradiation with 365 nm UV light resulted in the transformation of about 30 % trans-alkene to cis-maleate form, thereby affording amorphous polyesters.© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
- 是否译文:
- 否