The banded textures in the films of a thermotropic liquid crystalline poly(aryl ether ketone) containing a lateral chloro group have been studied by means of transmission electron microscopy(TEM), electron diffraction(ED) and atomic force microscopy(AFM). The crystallization induced banded texture without external shear can be formed when the thin films were annealed at the temperature range(320—330 ℃) of the liquid crystalline state from the melt. The results show that the banded regions have high orientation of single crystal based on the orthorhombic packing and the growing direction of the bands is along the b axis of the crystals. This kind of single crystal like bands is due to the different orientation of the packing molecular chains. The molecular chains of the dark bands in the bright field electron micrograph are perpendicular to the film plane, while the ones of the bright bands are tilt along the b axis with the tilt angle upto ±20°. [WT5HZ]
Novel thermotropic liquid crystalline poly(aryl ether ketone) was synthesized via the random copolycondensation of 4,4′ difluorobenzophenone, 4,4′ biphenol and tert butylhydroquinone. The results of differential scanning calorimetry, polarizing light microscope and X ray diffraction confirmed the liquid crystalline property of the polymer. The polymer may be of great use in blending with normal poly(aryl ether ketone)s.
The spreading behavior of new type of chiral and achiral rigid cyclic oligomer on the water surface was investigated by measuring the surface pressure(π) area( A ) isotherms, with the aim of comparison of new type LB films of chiral and achiral rigid cyclic oligomers. Molecular resolution atomic force microscope images of the Langmuir Blodgett(LB) film was observed and the structure of their two dimensional crystals on the basal plane of mica was studied.
A kind of highly fluorinated bisphenol monomer was synthesized. It was characterized by FTIR, 1H NMR and MS. 6F PEEK and 6F PEEKK were prepared via aromatic nucleophilic substitution, based on [3,5 di(trifluoromethyl)] phenylhydroquinone and difluoro monomers. The T gs of 6F PEEK and 6F PEEKK are 423 and 436 K, respectively. The 6F polymers exhibit a high thermal stability and good solubility. The flexible, creasable and transparent thin films were easily obtained by compression moulding and solution casting.
