Expandable Graphite

Intumescent and halogen-free flame retardant for thermoplastics and polyurethane resins. The expandable graphite is an intumescent flame retardant manufactured using natural graphite flakes (layered crystals consisting of sheets of carbon atoms).the flakes are oxidated by using sulphuric acid. When expandable graphite is heated at high temperature, it expands up about 100 times to its original volume.

The expanded flakes appear like « worms» having a circumference of 0,6 – 1,2 cm and length of several centimeters.

Expanded graphite acts as a char that covers the entire burning surface,

slowing the spread of the flame.

It is particularly suitable for thermoplastic elastomeric polymers with low softening point, and for two-component polyurethanes.

The typical addition level range is  15%-25% depending on the polymer.

It is very important to select the correct grade having an expansion temperature lower than polymer process one.limero.