Viscometric study on the interactions of polymers of the poly(benzazole) family with nylon 66

The criteria of polymer–polymer miscibility determined by dilute-solution viscometry are reviewed and this method was applied to study blend systems of rigid-rod (or semi-rigid) polymers and flexible polymer. The interactions of poly(benzazole) family (short as PBZs) with nylon 66 were investigated in methanesulfonic acid using dilute-solution viscometry (DSV) criteria and differential scanning calorimetry. Then the DSV data were analyzed by several different criteria reported previously to find out which criterion is more efficient and reasonable; moreover, the miscibility of the PBZs and nylon 66 was studied in detail. It was observed that PBO molecules have the strongest interaction force with nylon 66 molecules in the four blend systems presented in this paper.