Waterproof Performance of Polymer-Modified Cement Mortar

This paper tested the capillary water absorption, impermeability and cracking of cement mortars modified with three polymers respectively and founded the correlation of cracking with the waterproof performance. The results show that with the polymer content increasing, especially as the polymer/cement ratio (m(p)/m(c)) increases from 0% to 5%, the reduction in the capillary water absorption and the penetration depth of water into mortar is significant. When the m(p)/m(c) is more than 15%, the increase of the m(p)/m(c) in all mortars has little effect on the capillary water absorption and the penetration depth. For the purpose of reducing the cracking weighted value, the styrene-butadiene rubber (SBR) dispersion and the styrene-acrylic copolymer (SAE) powder are superior to the SAE dispersion. Regardless what kinds of polymers, the capillary water absorption and the penetration depth of water into mortar show exponential growth with the increasing cracking weighted value.