摘要 |
<p>Fire resistant syntactic foams are formed from a resol cold curing phenolic resin reacted with a partial phosphate ester, the ester comprising 5 to 15% of the weight of the resin calculated on the solids of both the partial phosphate ester and the phenolic resin, and expanded with hollow glass spheres of effective specific gravity between 0.15 and 0.35 and average diameter between 30 and 200 microns, mixed with the resin and ester at +/-15% of the critical pigment volume concentration and allowed to cure at below 70 DEG C. The foams may be used to form fire resisting duplex or sandwich structures.</p> |