Wide-angle X-ray diffraction techniques are employed to characterize the structure of 'as-made' and heat-treated fibres produced from nematogenic poly(m-phenylene terephthalate), where the molar fraction of the disruptor m-phenylenedioxy units is 0.25. As in the case of previously investigated poly(p-phenylene isophthalate)s, the 'as-made' fibres consist of a paracrystalline array of chains aligned along the fibre axis. Heat-treated fibre contains a mosaic of thin crystallites, consisting of m-phenylene terephthalate sequences, embedded in a paracrystalline matrix. A non-planar chain conformation, arising from the presence of m-phenylenedioxy units, is reflected in the shortening of the crystallographic repeat in the chain direction compared with that found for the poly(p-phenylene isophthalate) fibres.
Посилання на статтю:
Thermotropic polyesters: structure of poly(p-oxybenzoate-co- rn-phenylene terephthalate) fibres / David J. Johnson, Ismail Karacan and J. George Tomka* // Polymer. – 1993. – Vol 34. – P. 1749-1754.