Liquid flame retardants from the neutralisation of oligomeric partial phosphate esters

Abstract Title: Liquid flame retardants prepared by the neutralisation of oligomeric partial phosphate esters of polyols with imidazole Liquid flame retardant and intumescent additives form the neutralisation of partial phosphate esters of carbonific polyols with imidazole， where the partial phosphate esters have an orthophosphate to hydroxyl functionality of between 1:0.55 and 1:0.83， where the orthophosphate is derived from the decondensation of condensed phosphoric acid， condensed between 114% and 138% and the polyols have a hydroxyl content of greater than 37.7% of the molecular weight. The neutralisation of the partial phosphate esters using imidazole results in high viscosity flame retardant and intumescent liquids that are compatible with various polymers and resins. Preferably， the carbonific polyols are selected from 1，2-ethanediol， 1，3-propanediol， 1，4-butanediol and pentaerythritol. Also claimed is fire protected timber wherein the liquid fire retardant and intumescent additives are applied to the timber as a surface saturant or are vacuum impregnated into the timber. Resol phenolic resins; polyurethane foams， elastomers and films; unsaturated polyesters and vinyl esters; epoxy resins; polyurea and hydrid urea/polyurethane varnishes and films; solvent based coatings; and water based coatings and mastics are also claimed， comprising the liquid flame retardant and intumescent additives of the invention.