关键词: 苯丙乳液;力学性能;耐久性;改性机理

Abstract: In order to solve the problems of engineering seepage and concrete repair, the modified effect of styrene acrylic emulsion on cement mortar was studied.The results show that styrene acrylic emulsion can improve the flexural strength, tensile strength and bond strength of mortar, and the maximum increase is 42.8%,61.8%and 1.91 MPa respectively.The influence of styrene acrylic emulsion on the water absorption rate of mortar is obvious.The greater the amount of emulsion is, the smaller the water absorption rate is.Styrene acrylic emulsion can improve the frost resistance, impermeability, carbonization resistance,corrosion resistance and shrinkage of mortar.The age of 42 d,the shrinkage of modified mortar is 13.6%less than that of ordinary mortar.The seepage pressure of the modified mortar is 2.4 MPa,increasing by 0.9 MPa.The chloride penetration of modified mortar was reduced by 13.6%. And the greater the amount of emulsion is,the smaller the permeability of chloride ion is.

Key words: styrene-acrylic emulsion;mechanical property;durability;modification mechanism