Unusual Perpendicular Chain Orientation in a Smectic Liquid Crystal Polyester Subjected to Shear or Elongational Flow
作者： Stephen P. Church , Vijya Laxmi Patel , Nazir Khan , Zahir Bashir
DOI: 10.1080/10587259608042310
关键词: Shear flow 、 Isophthalic acid 、 Mesophase 、 Composite material 、 Perpendicular 、 Terephthalic acid 、 Isotropy 、 Liquid crystal 、 Polymer chemistry 、 Polyester 、 Materials science
摘要: Abstract In this work, we report on flow-induced orientation in two low molecular weight polyesters, both containing the smectic diol 4,1′-bis (6-hydroxy hexoxy) biphenyl (BHHBP) and either isophthalic acid (IA) or terephthalic (TA). The polyester of BHHBP IA has a mesophase, while crystallises cooling from isotropic melt without any mesophase formation. When TA was subjected to flow, chains were aligned parallel flow direction. contrast, when sheared elongational state, it found that surprisingly oriented perpendicular direction fibre axis. However, elongated molten normal with chain axis observed. Thus, appears have an association deformation state. information ...
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