Synthesis and Performance Testing of a New Type of Viscosity-reducing Polycarboxylate Superplasticizer

In order to improve the high viscosity problem of high-strength concrete caused by low water cement ratio, this paper uses allyl alcohol polyoxyethylene ether (APEG) as the functional monomer, acrylic acid (AA), maleic anhydride (MA), and specific functional ester monomers (VE) as functional monomers. Using the hydrogen peroxide (H2O2) - ascorbic acid (Vc) redox initiation system, a new type of viscosity reducing polycarboxylate superplasticizer (PCE-V1) was successfully synthesized at room temperature through aqueous free radical polymerization. The optimal synthesis process was determined through single factor and orthogonal experiments, and the obtained samples were characterized for structure and tested for performance. The characterization results indicate that the number average molecular weight of PCE-V1 is 6743 g/mol, and the product structure conforms to the design. The performance test of PCE-V1 in concrete shows that at the same dosage, the emptying time (3.35 s) of concrete poured with PCE-V1 is significantly shorter than that of conventional PCE (7.35 s), the plastic viscosity (2.3 Pa · s) is also lower than that of the control group, and the compressive strength at all ages is comparable to that of commercially available viscosity reducing water reducers. PCE-V1 not only maintains the strength of concrete, but also has a better viscosity reduction effect, which provides an effective solution for improving the workability of high-strength concrete.