Effect of the initial temperature on the water-reducing performance of polycarboxylate-based superplasticizers

In order to study the effect of the temperature of reaction system on the properties of polycarboxylate-based superplasticizers (PC) and on the cement workability, the PC are synthesized in different initiatory temperature from 10 C to 40 C. Fourier transform infrared spectroscopy (FTIR), and gel permeation chromatography (GPC) are used for structural characterization. The experimental data show that the PCs synthesized at different initiatory temperature have similar functional groups but disparate molecular weight and its distribution. As a result, the PCs synthesized at the higher initiatory temperature of reaction system possess lower molecular weight and narrower distribution, resulting in higher initial fluidity but smaller fluidity retention capacity.