A novel inherently hydrophobic and physicomechanically robust coconut oil-based polyurethane-modified mortar

Jason Jon Joshua B Paraguya; Roger G Dingcong Jr; Hernando P Bacosa; Gerard G Dumancas; Arnold C Alguno; Maria Sheila K Ramos; Roberto M Malaluan; Arnold A Lubguban

doi:10.1038/s41598-025-25112-2

A novel inherently hydrophobic and physicomechanically robust coconut oil-based polyurethane-modified mortar

Sci Rep. 2025 Nov 19;15(1):40664. doi: 10.1038/s41598-025-25112-2.

Authors

Jason Jon Joshua B Paraguya^{1

2

3}, Roger G Dingcong Jr¹, Hernando P Bacosa^{1

2}, Gerard G Dumancas^{4

5}, Arnold C Alguno^{1

6}, Maria Sheila K Ramos⁷, Roberto M Malaluan^{1

7}, Arnold A Lubguban^{8

9}

Affiliations

¹ Center for Sustainable Polymers, Mindanao State University-Iligan Institute of Technology, 9200, Iligan City, Lanao del Norte, Philippines.
² Department of Environmental Science, School of Interdisciplinary Studies, Mindanao State University-Iligan Institute of Technology, 9200, Iligan City, Lanao del Norte, Philippines.
³ College of Forestry and Environmental Studies, Mindanao State University - Maguindanao, 9601, Dalican, Datu Odin Sinsuat, Maguindanao del Norte, Philippines.
⁴ Department of Chemistry, New Science Building, North Carolina Agricultural and Technical State University, 1601 East Market Street, Greensboro, NC, 27411, USA.
⁵ Honors College, Henry E. and Shirley T. Frye Hall, Suite 110, North Carolina Agricultural and Technical State University, 1601 East Market Street, Greensboro, NC, 27411, USA.
⁶ Department of Materials and Resources Engineering and Technology, Mindanao State University - Iligan Institute of Technology, 9200, Iligan City, Lanao del Norte, Philippines.
⁷ Department of Chemical Engineering and Technology, Mindanao State University - Iligan Institute of Technology, 9200, Iligan City, Lanao del Norte, Philippines.
⁸ Center for Sustainable Polymers, Mindanao State University-Iligan Institute of Technology, 9200, Iligan City, Lanao del Norte, Philippines. arnold.lubguban@g.msuiit.edu.ph.
⁹ Department of Chemical Engineering and Technology, Mindanao State University - Iligan Institute of Technology, 9200, Iligan City, Lanao del Norte, Philippines. arnold.lubguban@g.msuiit.edu.ph.

Abstract

Water penetration in mortar structures has long been a significant challenge in the construction industry, resulting in metal bar corrosion, structural deterioration, reduced durability, and increased maintenance costs. Hence, enhancing water resistance is crucial. While surface coatings are common solutions, they are often costly and require frequent maintenance. To address this concern, this study presents a novel coconut oil (CO)-based polyurethane (PU)-modified mortar, leveraging the intrinsic hydrophobic properties of CO owing to its saturated fatty acid structure. Different concentrations of COPU (0-7 wt.%) were investigated to determine the optimal formulation. The characterization results indicated enhanced hydrophobicity, with a water contact angle of 125° achieved at the 2 wt.% COPU addition to the PMM mixture, compared to 110° of the control sample. Additionally, the water absorption test demonstrated a significant 54 wt.% reduction compared with that of pristine mortar, attributed to the gap-filling and binding actions of the COPU matrix with ettringites, as evidenced by SEM analysis. This modification also resulted in a 40 wt.%, being the highest improvement in compressive strength (from 13.1 to 18.4 MPa at 2 wt.% COPU) and a slight reduction in density. Additionally, the prepared samples were evaluated using thermogravimetric analysis, X-ray diffraction, and X-ray fluorescence analyses. The findings in this work advance the field by presenting eco-friendly COPU-modified materials that improve water resistance and durability in mortar, promoting sustainable practices.