Effect of different curing temperatures on the hydration of polyacrylate emulsion polymer-modified cement

Polyacrylate emulsion polymer-modified cementitious material is a widely used building material, and its hydration characteristics at room temperature have been widely studied, but its actual use environment usually varies with seasonal temperatures, so its hydration characteristics at different temperatures still need to be understood. Here, we investigated the hydration characteristics of polyacrylate emulsion polymer-modified cement (PMC) at 5, 20 and 40 degrees C. A variety of methods including calorimetry, thermal analysis, X-ray diffraction analysis, Fourier infrared spectroscopy and mercury intrusion porosimetry were used to gain a comprehensive understanding of the different behaviors. In conclusion, low and high temperatures have similar effects on the reduction and increase of compressive strength of the modified mortar, whereas the compressive strength of the unmodified mortar decreased substantially at low temperatures and increased slightly at high temperatures. This phenomenon is confirmed by the results of XRD and thermal analysis. The addition of the polymer increases the number of harmless and harmful pores in the cement and high temperature further increases the number of harmful pores. The change in mechanical properties is the result of the combined effect of the degree of hydration and the pore structure parameters.