Expandable graphite (sulfate-intercalated)

Expandable graphite is an intercalated graphite material that expands when heated. Decomposition of the intercalated species separates the graphite layers into a low-density, worm-like structure. In a suitable formulation, this expanded carbon barrier reduces heat transfer and limits movement of combustible decomposition products, providing an intumescent flame-retardant mechanism.

The selected material is expandable flake graphite, not already-expanded graphite or ordinary graphite lubricant powder. Its useful response comes from expansion within the host material or seal geometry. Flake size and expansion onset influence incorporation and fire response, while binders and other additives determine barrier cohesion. The same heat-triggered expansion can also fill gaps in fire-stop or sealing constructions.

Typical Applications

• Flame-retardant polyurethane foams: Used in appropriate foam formulations to create an expanded graphite barrier when exposed to fire or intense heat.
• Intumescent coatings and fire-stop products: Used in formulated coatings, collars and gap-sealing materials where thermal expansion helps obstruct the passage of flame and hot gases.
• Expandable gasket and sealing compounds: Used in suitable sealing constructions where heat-induced volume increase assists gap closure or formation of a protective carbon layer.

Specifications

Specifications describe the standard grade. Tolerance, test method and documentation package are confirmed per order.