Helical Polyacetylene‐Based Switchable Chiral Columnar Phases: Frustrated Chain Packing and Two‐Way Shape Actuator. Issue 17 (17th August 2016)

• Record Type: Journal Article
• Authors: Wang, Jun; Liu, Xiao‐Qing; Ren, Xiang‐Kui; Zhang, Ben; Yang, Shuang; Cao, Yu; Liu, Feng; Lotz, Bernard; Chen, Er‐Qiang
• Is Part Of: Chemistry, an Asian journal. Volume 11:Issue 17(2016)
• Page Start: 2387
• Page End: 2391
• Publication Date: 2016-08-17
• Subjects: chirality -- frustration -- liquid crystals -- polymers -- two-way shape actuation; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/asia.201600879
• Languages: English
• ISSNs: 1861-4728

Abstract

Abstract: Chiral columns formed by a helical cis ‐polyphenylacetylene (PPA) derivativeP1 are reversibly switched during a phase transition between two chiral columnar phases: the frustrated Φh 3D‐SL phase containing four chains at low temperature and a hexagonal columnar phase Φh at high temperature, accompanied by a simultaneous conformational change. The helix–helix transition along the PPA backbone during the Φh 3D‐SL ‐Φh transition makes the uniaxially orientedP1 capable of reversibly and reproducibly elongating (132 %) upon heating and contracting upon cooling, exhibiting the behavior of a two‐way shape actuator. Abstract : Let's twist to activate frustration : A four‐chain superlattice Φh 3D‐SL is proposed in a helical polyphenylacetylene derivative as a new mode of frustration, where the frustrated "lone" chain could switch its chirality opposite to that of the neighbors. Thermally reversible two‐way shape actuation is achieved by the conformational isomerization during Φh 3D‐SL to Φh transition.