SELF-LUBRICATING POLYBENZIMIDAZOLE-CONTAINING COMPOSITION

摘要

A composition, containing a polymeric blend and internal lubricants, wherein said blend consists essentially of from about 60 to about 100 weight percent of polybenzimidazole and from about 0 to about 40 weight percent of poly(aryletherketone), and said lubricants consist essentially of graphite and boron nitride in a weight ratio of about 1:10 to about 10:1, respectively. The polymer solution is pumped from a reservoir through a filtering system (28) before feeding it through the first inlet of nozzles (22). To aid atomization, a gas such as air or nitrogen is fed into a second inlet of the nozzles (22). An atomization reactor system is utilized to form the highly porous particles of the invention. The reactor system (10) has a cylindrical vessel (12) with upstanding side walls (14) and a coneshaped bottom (16) with an outlet (18) equipped with a particle separation system (20). Many nozzles are contained within the reactor. A recirculation pump (26) maintains suspension of the rounded particles in the non-solvent solution prior to discharging through outlet (18).