A remarkable water based flexible sealant system based on IIT technology

PD51 is a gunnable paste that dries to a flexible intumescent fire retardant rubber.

PD51 is the final result of an evaluation programme to use IIT powder to produce an intumescent sealant.

The formulation is simply:

China clay may be added up to 20% to reduce cost and increase stiffness. Pigments etc. may be added at will.

On internal testing as a seal to 25mm calcium silicate board:

  • the product sealed a 10mm gap
  • it gave a significantly lower back face temperature than when the board failed at delta 160°C
  • the sealant was still flexible on the cold face when cool

PD51 may also be used as a halogen free carpet backing.

Cold face post firing

Hot Face post firing

Looking down on the two faces from above