Identifying smectic I phase of main-chain PB-10 polyester consisting of 4,4′-biphenol and 1,10-dodecanoic acid by fibre X-ray diffraction

摘要: Abstract Spinnable main-chain PB-10 liquid crystal (LC) polyester was obtained for the first time by solid state polymerization after conventional melt condensation of 4,4′-biphenol and 1,10-dodecanoic acid. The smectic LC phase oriented uniaxially in fibre exhibited an X-ray diffraction pattern attributable to a C-centred monoclinic unit cell with  = 0.64 nm, b  = 0.90 nm, c  = 2.31 nm β  = 126° -axis parallel axis. type mesophase can thus be identified as I rather than H, speculated previously. Polymer chains are packed laterally into hexagonal lattice pass diagonally across layers. In smaller angle region, series peaks attributed lamellae stacking along direction spacing 41 nm. perpendicular polymer chain axis inclined layer.