Get ready for a world of self-growing and healing “living” materials – USC Viterbi

Magnification of algal cells: the building blocks for newly engineered ‘living’ materials
Anyone who grew up watching the cartoons of Walt Disney or Hayao Miyazaki is already used to a world where objects and materials have inner workings of their own, growing, healing and transforming.
For most of us, this world is reserved for childhood. For Professor Qiming Wang, the living potential of seemingly inanimate matter is a daily professional reality.
As the Stephen Wardrobe Early Career Chair in Civil and Environmental Engineering, his research harnesses the power of living microorganisms to create unprecedented self-healing and self-reinforcing materials. Now, a $3 million Future Manufacturing Research Grant in Ecomanufacturing from the National Science Foundation is funding a groundbreaking research initiative in which Wang is a co-principal investigator in collaboration with researchers from Texas A&M University and Caltech.
The study “Sustainable Manufacturing Using Living Organisms and Agriculturally Derived Materials” is inspired by the biological systems that involve living cells in the metabolism of biomass – comparable to the process of composting. The goal is to enable 3D printing-based methods that recycle and activate agriculturally derived waste materials such as discarded grass and biodegradable corn plastics. The secret agents in this process? Living microorganisms, including bacteria, algae and fungi.
Magical mugs and life on Mars
The research study is a good way to address two main problems facing our overstressed planet: the accumulation and waste of agricultural by-products and the need to repair and maintain engineered materials efficiently.
“Materials derived from agriculture have been severely undervalued and abused,” Wang said. “For example, most biomass is classified as solid waste, which is recycled as fuel or fertilizer, or sent to landfill.”
The proposed approach uses biocomposites with living organisms to create sustainable products traditionally made from petroleum-based plastics or natural wood. Since these products take on some properties of living organisms, they could heal like wounds or quickly generate themselves in an emergency.
“We tend to make a strict distinction between non-living, manufactured materials and organisms like trees and animals — natural structures made of cells that change and grow,” Wang said. Applications of this research could range from repairing objects — imagine the broken fragments of your favorite cup growing back together — to maintaining large infrastructure systems such as city subways, airplane runways, and road and bridge networks.
Wang also envisions the method for mass-producing emergency shelters and self-healing building materials in response to natural disasters. From there, his imagination leaps to extraterrestrial possibilities. “Another possible application is the construction of shelters on Mars. You could get microorganisms from the earth and then combine them with available raw materials to create new materials.”
Reconstruction with bacteria
Wang suggests that one of the method’s first uses could be in the manufacture of furniture and packaging materials — think of the expandable foam that protects your latest impulse purchase, or the inflatable plastic that fills those infamous brown boxes.
The research process is divided according to different categories of living organisms. Wang is studying the potential application of bacteria, while other researchers are focusing on fungi and algae.
“To visualize the types of materials we make, it helps to think of the texture and cushioning properties of an egg box,” Wang said. “The fragile eggs are protected by the egg carton restricting the movement of the eggs and dissipating energy – we call this ‘cushioning’. By crushing the materials into powder and adding bacteria as a living binder, the 3D printing process can be used to restore the original shape. This allows you to reuse the materials for almost unlimited cycles. The surface of the bacteria is covered with hairs that attach to the tiny particles like glue, forming strong bonds and turning the powder into a strong solid material with little bounce.”
A strategic vision for collective well-being
In the years to come, we’ll likely see the world more like Wang—not through a radical retraining of the mind, but simply because eco-friendly products that can grow and heal are becoming more commonplace.
Widespread use of the new method would create domestic manufacturing jobs and utilize more materials that are readily available in the United States. In addition, the project includes an education and staff development plan to train students and professionals in the principles of green manufacturing. From prioritizing environmental stewardship to engineering for disaster resilience, the project is in direct alignment with the NAE Grand Challenges for Engineering and the strategic vision of Sonny Astani’s Division of Civil and Environmental Engineering.
Adopting the mindset of Wang and his team can also have a positive impact on mental health.
As more and more materials seem to have life around us, it will likely impact the way we go about our days and feel connected to our surroundings as well. Both ancient philosophers and contemporary indigenous communities take it for granted that humans are the living products of a living planet. Why don’t we apply this mindset to the things we make?
Released May 26, 2023
Last updated on May 26, 2023