Study on waterproof mechanism of polymer-modified cement mortar

Abstract

In order to clarify the effect and influence mechanism of polymers on the waterproof performance of cement mortar, the effects of three polymers on capillary water absorption, impermeability, porosity and cracking of cement mortar were studied. The correlation between porosity and waterproof performance was analysed and the waterproofing mechanism of polymer-modified mortar was explored. The results show that waterproof performance, characterised by capillary water absorption and impermeability, was significantly improved by all three polymers but to different extents. The cracking weighted value declined and open porosity decreased with an increase in polymer dosage. The penetration depth of water into mortar and the capillary water absorption showed linear and exponential growth, respectively, with an increase in open porosity. The polymers were found to improve pore structure and refine porosity of >50 nm and thus weaken the negative effect of porosity on the waterproof performance of mortar.