Hydrophobicity Improvement of Cement-Based Materials Incorporated with Ionic Paraffin Emulsions (IPEs)

Abstract

Cement-based materials are non-uniform porous materials that are easily permeated by harmful substances, thereby deteriorating their structural durability. In this work, three ionic paraffin emulsions (IPEs) (i.e., anionic paraffin emulsion (APE), cationic paraffin emulsion (CPE), and non-ionic paraffin emulsion (NPE), respectively) were prepared. The effects of incorporation of IPEs into cement-based materials on hydrophobicity improvement were investigated by environmental scanning electron microscopy (ESEM), Fourier transform infrared (FTIR) spectroscopy, transmission and reflection polarizing microscope (TRPM) tests and correlation analyses, as well as by compressive strength, impermeability, and apparent contact angle tests. Finally, the optimal type and the recommended dose of IPEs were suggested. Results reveal that the impermeability pressure and apparent contact angle value of cement-based materials incorporated with IPEs are significantly higher than those of the control group. Thus, the hydrophobicity of cement-based materials is significantly improved. However, IPEs adversely affect the compressive strength of cement-based materials. The apparent contact angle mainly affects impermeability. These three IPEs impart hydrophobicity to cement-based materials. In addition, the optimal NPE dose can significantly improve the hydrophobicity of cement-based materials.

Mechanisms of Air Entraining of Proteins in Cementitious Materials

“…The measured contact angle is dependent on the method and type of cement hydrophobization . External surface applications such as coating generally give higher contact angles compared to internal mixing of the hydrophobizing agent in concrete. , Although contact angles as high as 162° for superhydrophobic cement have been achieved, , the normal range of contact angles in the literature for internally hydrophobized cement paste is lower, and plain cement samples have an angle around 40–50°, ,,, which is consistent with the corrected contact angle of C-Ctrl in this study. The measured contact angles, displayed in Figure , have a range of 20–50°, and since the r factor is much larger than 1 for all samples, corrected contact angles increase to a range of 40–70°.…”

Synthesis and Characterization of Hydrophobic and Self Healing Concrete Materials Based on Microorganisms

“…According to Huo et al (2020), Syaputri et al (2021), and Salam et al (2021) hydrophobic layers made on cement mortar using polymer materials show optimal results as proven by the comparison of compressive strength to standard mortar. Apart from that, the contact angle obtained is still very low and it has not been used as a bacteria-based self-healing mortar which can provide durability and strength to concrete.…”