Abstract: Sintered polybenzimidazole articles are obtained by compacting a particulate, dried polybenzimidazole resin under a pressure of 2,000 to 10,000 psi in a mold, heating the formed article to a temperature in the range of 825.degree. to 950.degree. F. for at least four hours, cooling the polybenzimidazole article to below 800.degree. F. while maintaining the article under a pressure of 2,000 to 10,000 psi, and thereafter heating the constrained formed polybenzimidazole article to a temperature in the range of 825.degree. to 950.degree. F. for at least one hour.