Evaluation on the consumption and performance of polycarboxylates in cement-based materials

- The absorption and coprecipitation of 6 PCE polymers are investigated.
- Their absorbed consumption and consequent flow of superplasticized cement pastes show time dependence.
- A relation between the PCE consumption and the yield stress of the superplasticized cement pastes can be finally obtained.

The addition of polycarboxylate based surfactants cause particles dispersion in cementitious materials and enhances their fluidity. The polymeric structures of the polycarboxylates have been formulated to meet various performance requirements such as water-reducing and consistency-maintaining. A trend on the relation between the polymeric structures and the resultant performance certainly exists, but its modeling is hardly obtained due to uncertainty on the polymeric structures as well as cement compositions. The degree of adsorption of the a polycarboxylate on cement particles is then taken to describe its performance. The rheological properties of plasticized cement pastes were evaluated and discussed to quantitatively analyze the effect of the adsorption of various polycarboxylates.