Factors influencing the fire-resistance of epoxy compositions modified with epoxy-containing phosphazenes

Abstract

The fire-resistance (State Standard GOST 28157-89, analogue of UL-94 test) of epoxy compositions based on D.E.R.-330 resin, isomethyltetrahydrophthalic anhydride and new epoxy-containing aryloxycyclotriphosphazenes was studied. Thermogravimetric analysis and microstructural studies of the coke residue formed during combustion were carried out. It has been determined that resistance to combustion of the cured compositions increases significantly as grows phosphazenes content in them. This is due both to the increase in the amount of porous coke residue formed during combustion (which acts as a barrier to flame propagation and heat transfer from the flame to the sample), and to the increase in the size of the pores formed therein. The obtained data can be used to create tough and flame-resistant composites for microelectronics, aviation and other industries.