Influence of polycarboxylate superplasticizers with different molecular structures on rheological properties of glass bead suspension at different resting times

作者：Yanliang Ji, Alexander Mezhov, Shukai Wang, Dietmar Stephan · 发表于：Colloids and Surfaces A Physicochemical and Engineering Aspects · 年份：2024 · DOI：10.1016/j.colsurfa.2024.133583 · 被引用次数：4 · 研究领域：Innovations in Concrete and Construction Materials、Polymer Nanocomposites and Properties、Soil and Unsaturated Flow

Using an inert glass bead suspension, the study explores the interaction between various PCE superplasticizers, ions and investigates how it affects rheological performance during resting. To understand the underlying mechanisms, surface charge properties, adsorption, aggregates amount, and size of PCE during resting were measured. Results showed that yield stress increased with time, mainly when a high PCE dosage was used, and the modulus from strain sweep experiments agreed with the yield stress variations. The increase in zeta potential value and decrease in aggregate amount explain the decrease in yield stress in the non-PCE sample but are inconsistent with the increase in yield stress in presence of PCE. The PCE clusters' size increases during resting, and increasing PCE adsorption does not disperse the glass bead particles. In addition, compared to the amount of carboxylate group, the molecular weight of PCE is more dominant in increasing the yield stress during resting. The increase in yield stress could be explained by the increase in the bridging and depletion forces due to the increasing size of the PCE cluster. Another possible reason is that non-adsorbed PCE clusters may form a polymer network that restricts the movement of the particles.