Binder emulsions for bituminous materials - prepd. by adding oxidising, polymerising and/or reducing agents then acid salts and finally emulsion breakers

摘要

A binder emulsion is prepd. by (1) adding to an anionic mother emulsion in any sequence a strong oxidising agent and/or polymerising or reducing agent as well as, opt. hydrolysed proteins and/or other elastomers to stabilise the anionic mother emulsion to form a separate continuous or a discontinuous phase primary emulsion accumulated on the solids, (2) adding acids and/or acid salts to the emulsion to form the final emulsion and (3) depending on the deposition conditions adding emulsion breaking substances such as elastomers, alkaline earth metal oxides and/or organic solvents and/or hydraulic binders, chalks etc. to aid pptn. The anionic mother emulsion comprises 50-65 wt. % acidified binder water up to 100 wt. % including approx. 0.3 wt. % (w.r.t. binder) NaOH or KOH, can be modified to give an acidic neutral or basic character suited to the opt. desired properties of the solid and may be opt. stabilised by additional filler and/or hydraulic binder and/or chalk and/or elastomers. The emulsion may be varied from a wide acidic to basic range smoothly and the breaking properties and adhesion on solids may be adjusted easily. The emulsion can be easily modified depending on its final use.