Use of inorganic polymer to improve the fire response of balsa sandwich structures

The study presented in this paper deals with the fire performance of balsa sandwich panels made using inorganic Geopolymer resin and high-strength fiber facings. A thin layer of a fire-resistant paste composed of Geopolymer and hollow glass microspheres was applied to the facings to serve as a protective fire barrier and to improve the fire resistance of the sandwich panels. Using 17 sandwich panel specimens, the primary objective of this program was to establish the minimum amount of fireproofing necessary to satisfy the Federal Aviation Administration (FAA) requirements for heat and smoke release. The influence of this fireproofing insulation on the increase in mass of the panels was also evaluated. The system is simple and inexpensive to manufacture, and a 1.8-mm-thick layer of fireproofing satisfies the FAA requirements for both heat release and smoke emission.