Synthesis and Properties of Flame-Retardant Waterborne Emulsion Derived from O-Cresol Formaldehyde Epoxy Resin

Abstract

By modifying O-cresol Formaldehyde epoxy resin with DOPO and Diethanolamine, and then neutralized by acetic acid, phosphorous-containing epoxy emulsion with excellent flame retardancy can be obtained under strong agitation. Diethanolamine opening rate and neutralized degree to the formation of epoxy emulsion were optimized. The flame-retardant property of the cured phosphorous-containing epoxy resin was test by UL-94, LOI and TGA method. The result shows that when the opening rate of Diethanolamine is 25.0% and the neutralized degree is 95.0%, stable epoxy emulsion can be obtained. When phosphorus content of the epoxy resin was 3.0wt%, the LOI value of the resin can be reach to 39.2 and pass the UL-94 test，the 700°C char remaining is 30.0wt%. The result shows that the flame retardant mechanism of the phosphorous-containing epoxy resin is mainly through a condensed- phase mechanism.