【摘 要】
：
We synthesized a crystalline helical polyphenylacetylene derivative (P5*) with high cis content (96%) using Rh(nbd)B(Ph)4 as the catalyst.The chemical structure of P5* is shown in Fig.la.Bearing small
【机 构】
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Department of Polymer Science and Engineering and Key Laboratory of Polymer Chemistry and Physics of
【出 处】
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Seventh International Symposium On Engineering Plastics (第七届
论文部分内容阅读
We synthesized a crystalline helical polyphenylacetylene derivative (P5*) with high cis content (96%) using Rh(nbd)B(Ph)4 as the catalyst.The chemical structure of P5* is shown in Fig.la.Bearing small chiral moieties of (s)-2-methylbutyl on the pendant groups, the chirality could be transferred from the pendant groups to the main-chain, inducing a preferential helical conformation of the PPA backbone detected by CD in film (Fig.1b).The one-handed helical chains of P5* could self-organize into a crystal form with a hexagonal superlattice at low temperature, which was determined by 2D-XRD and AFM (Fig.2).Upon heating, P5* would change into a hexagonal columnar liquid crystalline phase.
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