Improving Infrastructure through Slurry Rheology Control technology

Concrete is made from a mixture of water, cement, sand, and gravel, and the strength of the concrete depends on the ratio of water to cement. Lower water content improves strength, but it also reduces the fluidity of the mixture, making it harder to work with. We attacked this dilemma by focusing on the dispersion of cement particles, searching for a chemical that exhibited optimum adsorption on the surface of cement particles for good dispersion. The result was Mighty, a high performance AE water reducing agent (superplasticizer) that enabled the preparation of concrete combining both workability and strength, even with low water content. More recently, we have developed a variety of agents to boost productivity in concrete casting, as by accelerating strength gain for faster removal of mold or imparting high fluidity for improved workability.

We have also met the challenge of preventing washout of poured concrete in connection with such projects as tunnels in groundwater flow zones, embankments, seawalls, and land reclamation. Environmental safeguards to prevent washout into freshwater or seawater were adding to the cost and duration of construction. Applying our expertise in interface science, Kao developed Visco Top, a rheological modifier that exploits the unique viscoelasticity of threadlike stringy micelles. Visco Top inhibits separation of concrete materials to prevent washout, without sacrificing the mixture’s injectability, for safe and efficient construction.

Kao will continue building on its expertise in the control of slurry rheology to develop new technologies that contribute to the improvement of social infrastructure.