Authors Antipov, E.M. ; Polikarpov, V. M. ; Antipov, E. E. ; Razumovskaya, I. V. ; Stamm, M. ; Lemstra, P. J.
Title A comparative analysis of the structure of aromatic copolyesters and their boron-containing analogs
Date 01.03.2002
Number 43862
Abstract Temperature-induced evolution in the structure of newly synthesized boron-containing copolyesters and their fully aromatic analogs was studied by X-ray diffraction, DSC, and optical polarization microscopy. As opposed to boron-containing polymers, the macromolecules of which are composed of rigid mesogenic fragments separated by flexible spacers, rigid-chain boron-containing copolyesters were found to be incapable of forming a columnar mesophase with two-dimensional pseudohexagonal packing of the centers of conformationally disordered chains. Meanwhile, a fully aromatic analog proves to be capable of a similar transformation: a three-component copolyester consisting of methylhydroquinone moieties, as well as the residues of terephthalic and isophthalic acids, demonstrates a second-order transition from an orthorhombic crystalline phase to a pseudohexagonal mesomorphic state at elevated temperatures.
Publisher Polymer Science Series A
Citation Polymer Science Series A 44 (2002) 247-257
Tags reduced flow resistance liquid-crystalline copolyester temperature window polyethylene rheology

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