THE MORPHOLOGY OF RIGID-ROD POLYMERS AND MOLECULAR COMPOSITES RESULTING FROM COAGULATION PROCESSING

The effects of processing conditions on the morphology of molecular co mposite films are examined by optical and electron microscopy. During coagulation processing from solutions in methanesulfonic acid (MSA), r igid-rod polymer, such as poly(p-phenylenebenzobisoxazole) (PBO), phas e separates into undesirable aggregates. The coagulant and the method of its introduction have been found to exert a strong impact on the fi nal film morphology. A quench of a PBO solution in MSA into a water ba th results in a three dimensional interconnected network of PBO, while a slower introduction of water results in a more amorphous material. A computer simulation program of the coagulation process has been deve loped to better understand the different structures emerging from coag ulation processing of molecular composites. The simulation results are in qualitative agreement with the experimental observations.