Cationic Emulsions

The chemical surface-active agents, which serve as emulsifiers for asphalt emulsions are classified chemically by the electrochemical charge, which they attain when they dissociate in the water solution. In the case of cationic emulsions the chemical charge imparted to the emulsion is positive. The chemical type and quantity of surface-active agent used in the manufacturing process governs the process in which that asphalt emulsion can be used.

There are three major classifications of emulsion grades: Rapid Set, Medium Set and Slow Set. The terms “rapid, medium, and slow” were meant to relate to the amount of time it took for the emulsion to cure.
It was also related to the amount of mixing that can be performed before the emulsion breaks. The mixing time and the rate of cure are still related today, the emulsions which allow the longest mixing time generally take the longest to cure, and emulsions which allow very little mixing time are those which set and cure most rapidly.