THE SOLUTION STRUCTURE OF LIQUID-CRYSTAL POLYMERS WITH SMALL LIQUID-CRYSTAL THERMOSET MALEIMIDES AND NADIMIDES

The solution structure of the deuterated liquid-crystal polyamide poly mer (LCP) poly(p-phenylene-2-nitroterephthalamide), alone and mixed wi th small, rodlike, amide, liquid-crystal molecules (LCT) in N-methyl-2 -pyrrolidinone (NMP), is studied using small-angle neutron scattering. Measurements were made as a function of LCP concentration using diffe rent LCTs mixed at 20 and 40 wt% relative to LCP. Our motivation for s tudying this system comes from a need to connect solution structure wi th film morphology in processing these materials for high-performance molecular composites. Our analysis shows that the LCP in NMP forms lar ge domain-like structures. The presence of LCT breaks up the LCP domai ns into smaller structures, some of which are filamentous LCP-LCT aggr egates. This result suggests that the simple entropic description of t he solution behavior of mixtures of long and short rods is not adequat e in describing systems of this type.