Abstract: The invention under consideration concerns novel his-molecular-weight polyazoles, which are suitable for the production of fibers, films, membranes, and molded articles, on the basis of their high molecular weight, expressed as intrinsic viscosity, of at least 1.3 dl/g. Moreover, the invention under consideration describes a method for the production of high-molecular-weight polyazoles.

Abstract: A process is presented for the production of high molecular weight polybenzimidazole, in two steps. Step one: provide a first reaction vessel and charge it with at least one aromatic hydrocarbon tetraamine, and a heterocyclic ring making up the dicarboxylic component. Heat the reactants under agitation. Terminate the agitation while continuing to heat the reaction mixture to about 230° C. while allowing the reaction mass to foam. Cool the reaction mass to a friable foamed mass. Crush the friable foamed mass to obtain a ground prepolymer. Step two; provide a second reaction vessel, transferring the ground prepolymer to it. A pressure wash of the first reaction vessel and the means for agitation to obtain a second ground prepolymer. Transfer the second ground prepolymer to the second reaction vessel. Heat the ground prepolymer and second ground prepolymer under agitation to a higher temperature than the first step until the desired degree of polymerization is achieved.

Abstract: A process for the production of high molecular weight polybenzimidazole by one: providing a first reaction vessel; charging the reaction vessel with at least one aromatic hydrocarbon tetraamine, and a heterocylic ring making up the dicarboxylic component; heating the reactants under agitation in a substantially oxygen-free atmosphere with agitation until the agitator torque is about 1.5 times the torque before a rise in viscosity begins; terminating the agitation while continuing to heat the reaction mixture to about 230° C. while allowing the reaction mass to foam; cooling the reaction mass to a friable foamed mass; crushing the friable foamed mass to obtain a ground prepolymer; and two: providing a second reaction vessel, the second reaction vessel being a high intensity reaction vessel; transferring the ground prepolymer to the second reaction vessel; heating the ground prepolymer under agitation to over 315° C. at atmospheric pressure for a time of about 90 minutes.

Abstract: A process for a single-stage melt polymerization for the production of a high molecular weight polybenzimidazole which comprises the steps of: providing a reaction vessel having a means for agitation and a means for vacuum; charging the reaction vessel with reactants selected from: (A) a tetraaminiobiphenyl (TAB), and (B) a diphenyl isophthalate (DPIP); reacting the reactants under constant agitation and under a vacuum with an inert gas sweep; maintaining a reactant temperature which does not exceed 290° C. under constant agitation allowing pressure in the vessel to increase, with an inert gas sweep until a phase change is achieved, when the temperature reaches 250° C. pressure is increased to a slight positive pressure; and increase the reactant temperature and pressure within said reaction vessel while maintaining constant agitation and inert gas sweep, while maintaining a slight positive pressure. Preferably the vessel used in the instant invention is a high intensity reaction vessel.