What is the sulfonated asphalt

Sulfonated asphalt is an anionic high polymer product, which is mainly made of asphalt after sulfonation, emulsion and other treating process. The molecular structure is 一C一 C一，一C一S, and has strong bond energy, thus can resist high temperature.
The basic material is oil asphalt, and appears as easy breakable brown powder. Its density is 0.98g/cm3, and contains high water soluble content, and certain percentage of oil soluble content. Besides, it has fine emulsifying properties. It is applicable for all kinds of drilling fluid systems.
Sulfonated asphalt owns strong hydration property due to the sulfonic acid group it contains. When it is absorbed on the shale surface, the sulfonic acid group can prevent the hydration dispersion of shale particles thus to prevent and decrease collapse. Meanwhile, the water insoluble particles will fill bore hole and cracks, acting as plugging agent, and improving mud cake quality when absorbing on the shale surface. Besides, sulfonated asphalt also acts as lubricant and HTHP fluid loss reducer in drilling fluids.