Effects of Calcium Sulphoaluminate Expansion Agent and Magnesia Expansion Agent on Properties of Styrene-Butadiene Copolymer Dispersion Modified Mortar

Abstract

Abstract: The effects of calcium sulphoaluminate expansive agent (CSA) and magnesium oxide expansive agent (MEA) on the workability, mechanical properties and shrinkage properties of styrene-butadiene copolymer dispersion modified mortar were studied at 20 ℃, relative humidity 90% (RH90%) and 60% (RH60%). The results show that the fluidity of styrene-butadiene copolymer dispersion modified mortar increases first and then decreases with the increase of the dosage of the two expansion agents. At 90%RH and RH60%, the mortar with CSA mass content of 6% and 10% has the highest flexural and compressive strength, respectively. CSA effectively reduces the drying shrinkage of mortar under two kinds of humidity. At 90%RH, 8%MEA improve the flexural and compressive strength of mortar, and also effectively compensate the drying shrinkage of mortar in later period. At RH60%, 8%MEA reduce the mortar flexural and compressive strength, and can not effectively compensate the dry shrinkage of mortar.

Key words: styrene-butadiene copolymer dispersion modified mortar, expansion agent, mechanical property, shrinkage property, calcium sulphoaluminate expansion agent, magnesia expansion agent

CLC Number:

TU528

WEI Kuo, LIU Sifeng. Effects of Calcium Sulphoaluminate Expansion Agent and Magnesia Expansion Agent on Properties of Styrene-Butadiene Copolymer Dispersion Modified Mortar[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2022, 41(7): 2244-2250.

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