Determination of Optimum Glass Transition Temperature of Acrylic Acid Ester Copolymer to Improve Performance of Cement Matrixes

This study was conducted to determine an appropriate glass transition temperature of a polymer to improve performance of the polymer cement mortar and concrete. The glass transition temperature of the polymer, which was synthesized as a redispersible acrylic acid ester polymer, and physical properties of polymer cement mortar were evaluated. The polymer showed a lower glass transition temperature as the ratio of unsaturated hydrophobic ethylene monomer was increased. A decrease in glass transition temperature decreased the tensile strength, compressive strength, flexural strength, and volume change; increased the elongation, liquidity of polymer cement mortar, and adhesion; and delayed condensation. Scanning electron microscope and energy-dispersive X-ray spectroscopy results confirmed that, a polymer film formed inside the cement matrix made mostly of carbon around pores and cracks inside the cement paste. A glass transition temperature of 0 to -11 degree Celsius showed the best results. These results can be used for developing novel construction materials.