Expanded pyrolytic graphite; process for making expanded pyrolytic graphite; and insulation produced therefrom

摘要

A process for making lightweight, malleable, high temperature pyrolytic graphite material having uniform AB plane spacing from a dense pyrolytic graphite material by first heating the dense pyrolytic graphite material to a temperature of at least about 2900°C. Thereafter, the pyrolytic graphite material is heated with an intecalating agent at an elevated temperature; the intercalating agent preferably is washed from the treated pyrolytic graphite material; and the (washed) pyrolytic graphite material is heated at a temperature of about 700°C to about 1100°C for a sufficient time to form an expanded pyrolytic graphite material. The product is a stable, low density, non-friable, compressible, heat-graphitized pyrolytic graphite expanded by intercalation in the c direction of the AB plane spacing with remarkable uniformity and has excellent insulation characteristics. It is malleable, or may be rigidized.