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

Author(s): Seong-Soo Kim, Jeong-Bae Lee, Tae-Jun Cho, and R. Douglas Hooton

Publication: Materials Journal

Volume: 111

Issue: 5

Appears on pages(s): 521-530

Keywords: acrylic acid ester; glass transition temperature; polymerization; redispersible polymer powder

DOI: 10.14359/51686599

Date: 9/1/2014

Abstract:
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°C (32 to 12.2°F) showed the best results. These results can be used for developing novel construction materials.