Investigation of the possibilities of using nanoparticles in the synthesis and technology of fire safe rigid polyurethane foams that are safe for the working environment

The aim of the task was to synthesize fireproof rigid polyurethane foams with nanoparticles decreasing their flammability. Polyurethane foam was modified with systems of two kinds of nanoparticles based on compounds of layered silicate nanoclay(Nanofil 2 and Nanofil 5) and on zinc stannate (ZS) and, additionally, on expanded graphite.The influence of nanoparticles on the properties of modified polyurethane foams was evaluated with the following measurements: technological times, specific gravity, water absorption, viscosity of the polyols mixture, the aging of the foams in a dryer, foaming temperature, oxygen index flammability and cell structure. The obtained results revealed a good combination of compounds of zinc stannate with nanoparticles based on layered silicate nanoclay, not only because of an increase in the value of the oxygen index but also because of an improvement in the usability properties of polyurethane - polyisocyanurate (PUR-PIR) foams.Expanded graphite very clearly decreased the flammability PUR-PIR foams modified with nanoparticles.Flammability of the best systems of the newly developed PUR-PIR foams was checked with modern flammability tests: measuring combustion heat in a calorimetric bomb and testing with a cone calorimeter. Moreover, the concentration of nanoparticles of montmorillonite compounds was measured in laboratory air.