Developing Integral Hydrophobic Cement Mortar Composite Using Sustainable Carbon Nanomaterial: Wettability and Surface Energy

Abstract

Various forms of superhydrophobic carbon-based nanomaterials have been extensively attracted to advanced fields. Although it is widely implemented, its potential environmental impact and uneconomical has limited its utilization. To overcome these shortcomings, this article aimed to provide Carbon-based Sustainable Superhydrophobic (CSS) nanoparticles obtained from the pyrolysis of tyre waste. Firstly, CSS nanoparticles were characterized with microscopic, spectroscopic, and hydrophobic measurements. This article subsequently studied the development of hydrophobic cement composites using CSS nanoparticles and reviewed the advanced progress in the research of surface wettability and surface energy using a time-dependent contact angle measurement technique. Further, the role of CSS nanoparticles in cement composites is examined through mechanical strength and microstructure characterization. The water contact angle results showed that the cement composites with CSS nanoparticles achieved hydrophobic and exhibited the highest contact angle of 132.15º (over-hydrophobic) for 3wt%. The CM-3 mix has the lowest value of total (γ_S), dispersive (\({\gamma }_{s}^{d})\), and polar surface energy (\({\gamma }_{s}^{p})\) of 11.95 mJ/m², 11.63 mJ/m², and 0.324 mJ/m² respectively. Moreover, the compressive and flexural strength improved significantly with the addition of CSS nanoparticles, attaining maximum strength of 55.65 MPa (CM-2) and 7.8 MPa (CM-1.5), respectively. The 3wt% CSS nanoparticles are successfully disseminated with 10% SF, exhibiting a relatively high reduction of capillary absorption. Microstructure investigation shows that CSS nanoparticles are well entangled in SF, resulting in a dense and compacted matrix structure. Therefore, CSS particles will be an advanced and sustainable nanomaterial for developing an integral hydrophobic cement composite.

Graphical Abstract