New elastomer-based adhesive enables lighter, more carbon-efficient vehicles

Researchers at Nagoya University have developed a major breakthrough in structural adhesives for the automotive industry. This next-generation adhesive promises to revolutionize the bonding of materials by delivering unprecedented impact resistance, 22 times greater than that of traditional epoxy-based adhesives that do not incorporate any rubber additives.

By bonding car parts with a stronger, more flexible adhesive, it is possible to produce cars using lighter components, such as aluminum and fiber-reinforced plastic. The results were published in ACS Applied Materials and Interfaces.

“High-strength and durable structural adhesives are essential in the assembly of automobiles, aircraft and buildings,” says Atsushi Noro, a researcher at Nagoya University.

“Epoxy resin adhesives are widely used. However, they lack flexibility, making them susceptible to damage upon impact. To overcome this problem, we combined a hydrogen-bonded styrenic thermoplastic elastomer with an adhesive, resulting in a new type that offers both flexibility and exceptional impact resistance.”

This new adhesive was created in collaboration with Aisin Chemical Company. Its innovative adhesive suggests a new use for hydrogen-bonded styrenic thermoplastic elastomers, an earlier creation of Nagoya University.

A hydrogen-bonded styrenic thermoplastic elastomer is a polymer that exhibits rubbery properties, allowing it to stretch and return to its original shape. These properties have helped create a stronger adhesive with better stress dissipation upon impact.

Additionally, hydrogen bonds formed within the elastomer in the adhesive allow it to separate and reconnect in an instant under stress, further increasing its toughness.

This advancement has important implications for the automotive industry, as it addresses the need for stronger, more flexible adhesives capable of bonding dissimilar materials in lightweight, multi-material vehicle designs.

“Structural adhesives are expected to play a key role in reducing vehicle weight, which is essential for improving fuel efficiency and reducing emissions,” said Noro. “The adhesive’s ability to bond various materials, such as metals and fiber-reinforced plastics, enables lighter vehicles without compromising safety or performance. This development is a significant step forward in the quest for a carbon-neutral society.”

While it is expected to be a valuable tool in the automotive industry’s quest for sustainability and performance, the researchers hope that as research continues, it can be used in other industries, such as aerospace and construction, reducing the weight of materials used and improving carbon cost in these heavy industries.