Preparation and Application of Silane-Modified Polycarboxylate Superplasticizer in Concrete Viscosity Reduction

Abstract

To address the issue of high viscosity in the construction of high-performance concrete, researchers have developed silane-modified micro-cross-linked polycarboxylate superplasticizers (SPCEs) through free radical-initiated copolymerization. These SPCEs have been studied for their molecular structure, adsorption behavior in cement paste, and influence of silane content on rheological performance of cement paste and concrete. The experimental findings indicate that while SPCEs exhibit a slightly diminished water reduction rate, the viscosity of cement paste with SPCEs is lower compared to conventional polycarboxylate superplasticizer with equivalent fluidity. This is attributed to their enhanced adsorption capacity, reduced intrinsic viscosity, and smaller hydrodynamic radius. Compared to the control group, the concrete made with SPCE showed a decrease of 23.53% and 11.00% in the outflow times of T500 and V-funnel, respectively, along with a reduction of 19.43% in plastic viscosity. The condensation of silanol can enhance the hydration of cement during the intermediate and final phases, leading to an improvement in the strength of concrete in later stages. There was an 8.79% increase in intensity at 28 days compared to the control group. Consequently, micro-cross-linked SPCEs possess significant prospects for advancement and can be employed in high-performing concrete.