Adhesives play a crucial role in maintaining the integrity of our modern world, from securing our smartphones and cars to assembling furniture and packaging. However, the challenge lies in their sustainability. Researchers at Purdue University, led by Professor Jonathan Wilker, are on a mission to revolutionize adhesives with a completely eco-friendly system, as detailed in a recent Nature paper.
“Our current adhesives pose environmental issues,” Wilker explains. “Most glues are petroleum-based and do not break down, contributing to landfill waste and even ocean microplastics.”
Wilker’s team has delved into the science of adhesives, drawing inspiration from marine creatures like mussels and oysters, known for their remarkable sticking abilities. Their goal is to develop sustainable, affordable adhesives that match the performance of traditional counterparts found in hardware stores.
One pressing concern with current adhesives is their toxicity. Petrochemical-based glues emit harmful fumes, such as formaldehyde in plywood, which can harm human health. Nevertheless, people and industries favor these conventional adhesives due to their strength, ease of production, and cost-effectiveness. Any sustainable alternative must meet these standards.
Wilker’s lab conducts side-by-side tests of their innovative adhesives against commercial ones to ensure they perform as well or better. “Studying nature’s adhesives helps us design technologies for a greener future,” Wilker notes. “We aim to create bio-based, non-toxic adhesives with equivalent strength, allowing for easy bonding and disassembly.”
Moreover, cost-effectiveness and the availability of starting materials on a large scale are key design considerations. After experimenting with various sustainable ingredients, the team settled on epoxidized soy oil as a primary component. It’s readily available globally and affordable. They combined it with malic acid, found in apples, and tannic acid, reminiscent of the chemistry used by mussels to attach themselves. This combination resulted in an adhesive that is both cost-effective and eco-friendly.
“In the right conditions, our adhesives can match the strength of epoxies, the highest-performing class of adhesives,” Wilker reveals. “All components are bio-based, safe, and available in large quantities. Plus, the adhesive is easy to manufacture.”
The team’s research may lead to a family of sustainable adhesives that can be used across various applications. Their innovations could have far-reaching impacts in medical technology, industrial materials, and packaging, promoting a more sustainable way to keep our world together.
Wilker has taken steps to protect this groundbreaking work by disclosing it to the Purdue Innovates Office of Technology Commercialization, which has applied for a patent to safeguard the intellectual property.