An investigation on the effect of water-soluable polimers on the properties of cement and concrete

In this study, the effect of DMA-MMA diblock copolymer on the properties of ordinaryPortland cement and cement containing boron has been investigated. Variation in setting time,compressive strength, and volume expansion have been determined. Cement hydration wasmonitored by X-ray diffraction (XRD) and by Fourier transforms infrared spectroscopy, incombination with the thermoanalytical methods (TG/DTA). The microstructural observation ofthe hydrated cement paste was performed by scanning electron microscopy (SEM). The resultshowed that DMA-MMA prolongs the early setting time of the Portland cement and compositecement, and has no noticeable effect on the final setting time of the both cement types. TheDMAMMA diblock copolymer reduced the water-to-cement ratios (w/c) from 0.5 to 0.42,which improved the compressive strength of the mortars at all curing ages. The experimentalresults also indicated that the DMA-MMA does not only change the rate of cement pastehydration, but also the microstructure of calcium-silicatehydrate (C-S-H).