Aqueous air foams of polyhydroxy polymer

Abstract

A method of treating hazardous material or other substrate with an aqueous air foam, comprising the steps of (1) preparing an aqueous solution or dispersion comprising (a) water-soluble polyhydroxy polymer having a plurality of hydrogen-bondable 1,2- and/or 1,3-diol structures capable of complexation with the borate anion, B(OH).sub.4.sup.-, (b) polyvalent ionic complexing agent, such as borax, which crosslinks said polymer by hydrogen-bonding complexation, (c) foaming agent to impart persistence to the fluid air foam generated upon aeration of said solution or dispersion, (d) a pH modifier, such as sodium hydroxide or acetic acid, to impart an appropriate pH to the solution or dispersion necessary for time-controlled formation of gelled or viscous air foam from the fluid air foam, and (e) water as the major component of said aqueous solution or dispersion by weight; (2) aerating said aqueous solution or air-entrained, low density foam (or air foam) which is gelable or becomes viscous, generally at least 5 seconds after its formation; and (3) spraying, contacting or otherwise applying said fluid, aqueous air foam to exposed surface of said hazardous material or other substrate.