In a groundbreaking stride towards sustainable construction, researchers have developed an innovative foam mortar that not only enhances thermal insulation but also promotes waste reduction. This novel material, incorporating recycled polyethylene terephthalate (PET) waste as a partial sand replacement, offers a promising solution to the dual challenges of waste management and resource depletion. The study, led by Md Azree Othuman Mydin from the School of Housing, Building and Planning at Universiti Sains Malaysia, was recently published in *Scientific Reports* (which translates to *Nature Research Reports* in English).
The research explores the potential of PET waste, often discarded as environmental pollutants, to improve the thermal insulation properties of foam mortar. By processing PET waste into fine aggregate sizes and using it as a partial replacement for sand, the team created six mix proportions with varying PET replacement ratios. The results were impressive, with thermal conductivity decreasing from 0.31 W/mK to 0.26 W/mK and density reducing by up to 15%. “The use of PET significantly improved the thermal properties of the foam mortar,” noted Mydin, highlighting the material’s potential for enhancing energy efficiency in buildings.
While the compressive strength of the foam mortar decreased with higher PET content, ranging from 12.5 MPa at 0% PET to 9.8 MPa at 25% PET, the material remains viable for non-structural applications. The study also observed a 25–30% decline in flexural strength and a 20–25% decline in tensile strength, attributed to weakened interfacial bonding between PET and the cement matrix. However, durability tests revealed a 20% decrease in water absorption and a substantial reduction in chloride ion penetration at higher PET levels, indicating improved long-term performance.
Microstructural analysis confirmed the benefits of incorporating PET, showing more refined pore structures and homogeneous dispersion of PET particles. “These findings suggest that PET can be a sustainable alternative to traditional foam mortar, promoting environmentally friendly construction methods and the principles of the circular economy,” Mydin explained.
The implications of this research for the energy sector are substantial. As buildings account for a significant portion of global energy consumption, the adoption of materials with enhanced thermal insulation properties can lead to considerable energy savings. By integrating recycled PET waste into construction materials, the industry can also reduce its environmental footprint and contribute to waste management efforts.
This innovative approach to sustainable construction has the potential to shape future developments in the field, encouraging further research into the use of recycled materials in building products. As the demand for energy-efficient and eco-friendly solutions continues to grow, the foam mortar developed by Mydin and his team offers a promising step forward in the pursuit of a more sustainable built environment.