Project spotlight: Building a better world with bio-based composites

Cement production is responsible for about eight percent of global CO₂ emissions. Finding alternative, environmentally friendly building materials is essential to the United States goal of net-zero emissions by 2050. Researchers at Sandia National Laboratories’ Water Power and Materials Science programs are studying ways to manufacture low-carbon composites from recycled bio-based materials that could meet this need.

An early-stage technology, bio-based composites pose several complex research challenges. Sandia researchers partnered with the University of New Mexico to develop a bio-based polyurethane composite (BPC) as an alternative to Portland cementitious concrete, the most commonly used construction concrete. The carbon footprint for BPC is 50% lower than traditional concrete.

According to Mohammed Abdellatef, principal investigator on the project, “The goal is to push the boundaries in utilizing bio-based material for low-carbon composites. It’s exciting to see Sandia leading the research community in material and industrial decarbonization. This research could be considered the first step in a long journey of using bio-based material.”

By using benzoic acid and multi-walled carbon nanotubes (MWCNTs), researchers were able to produce a BPC with high thermal stability and excellent durability characteristics making the material an excellent alternative for construction and rapid repair applications in marine and other aggressive environments. BPC has a low elastic modulus (i.e., resistance to elastic or “springy” deformation), so the material has low tensile stress buildup from restrained shrinkage, which suppresses early-age cracking, helps maintain structural integrity and protects the reinforcement from corrosive environments.

Ongoing research on BPCs seeks to expand the development of multifunctional bio-based composites. Future research will focus on using a wider range of biomaterials, especially ones that are more plentiful, such as recycled lignin and algae. “The dream,” said Abdellatef, “is to effectively engineer multifunctional bio-based composites with suitable strength and durability to replace materials with a high-carbon footprint.” The BPC team earned Sandia’s Employee Recognition Award in innovation for their research in 2023 and currently is forming partnerships with academic and industry members to continue research on construction and other applications for BPCs.

To learn more about BPC, contact Mohammed Abdellatef. For more information on Sandia’s decarbonization efforts visit the Renewable Energy and Climate Security research programs.