IMPROVEMENT OF THE PROCESSABILITY OF ADVANCED POLYMERS

Low percentages of a thermotropic liq.-cryst. dihydroxybiphenyl-hydroquinone-hydroxybenzoic acid-isophthalic acid-terephthalic acid polyester were mixed with Ultem 1000 polyether-polyimide. The thermal and morphol. anal. revealed a 2-phase system. Rheol. measurements in shear flow were carried out in the temp. range of the existence of the mesophase. A significant drop of .apprx.30% in the Ultem viscosity occurred when the mixt. contains only 5% by wt. of the liq.-cryst. polymer. The effect of the addn. of the thermotropic polymer on the mech. properties of Ultem was also investigated, and the morphol. of the polymer systems was related to their mech. properties.