Effect of PDMS on the waterproofing performance and corrosion resistance of cement mortar

By Fajun Wang, Sheng Lei, Junfei Ou, Wen Li. 2020

175 citations recorded by the source corpus.

Abstract The currently used cement hydrophobic additives are either expensive or damageable during use, limiting their large-scale application on concrete. In this study, low-cost and commercially available polydimethylsiloxane (PDMS) is proposed as a cement admixture for the hydrophobic modification of cement mortar. The uniform distribution of PDMS in hardened cement mortar (HCM) attributes integral hydrophobicity to HCM. The PDMS modified HCM (M-HCM) surface exhibits superhydrophobicity, with a contact angle of 157.3° and a sliding angle of 8.7°. The superhydrophobic M-HCM is mechanically robust after being abraded for 110 m distance. In addition, the water absorption of the M-HCM reduced approximately 92.51%, and the corrosion resistance of the M-HCM obviously improved. The compressive strength and flexural strength of the M-HCM reduced by 30.9% and 18.1%, respectively, while the toughness of the M-HCM improved. Furthermore, the durability of the M-HCM against weathering, sulfate attack, and leaching significantly improved in comparison with the U-HCM. This type of mechanically robust superhydrophobic M-HCM material can be used in the waterproof concrete and anti-corrosive concrete.

Subfields: Civil and Structural Engineering, Earth-Surface Processes, Surfaces, Coatings and Films

View Paper: https://www.semanticscholar.org/paper/fd06a865b33a04e4d8439f30a4d44f6058052d01