Thermally conductive caulk

摘要

A thermally conductive caulk particularly suited for use in a phosphoric acid fuel cell is made by mixing graphite into a stable aqueous dispersion of polytetrafluoroethylene and fluorinated ethylene propylene such that the solids floc to form a paste. The paste is applied to the part to be caulked and then dried and heat treated. Caulks made according to the present invention have good thermal conductivity and absorb very little phosphoric acid.