Expandable graphite

The expanded flakes have a “worm-like” appearance and are generally several millimeters long.

[2] To produce expandable graphite, natural graphite flakes are treated in a bath of acid and oxidizing agent.Usually used oxidizing agents are hydrogen peroxide, potassium permanganate or chromic acid.

[3] Starting temperature and expansion rate depend on the production conditions and particle size of the graphite.

temperature and expansion rate are depending on the degree of fineness of the graphite used.

Expandable graphite is included in the chemical processes for paints and varnishes.