Researchers at Northwestern University have developed the first-ever two-dimensional (2D) mechanically interlocked polymer, a nanoscale material that combines exceptional strength and flexibility. This innovative material, which mimics the structure of chainmail, features 100 trillion mechanical bonds per square centimeter — the highest density of such bonds ever achieved. These interlocked bonds allow the material to dissipate force in multiple directions, significantly enhancing its toughness while maintaining lightweight properties.

Material Development
The creation process involved assembling X-shaped molecular building blocks into crystalline structures. Chemical reactions within these structures formed interlocked molecular layers. This approach enabled researchers to overcome previous challenges in creating mechanically interlocked polymers, which had been limited by inefficient and small-scale production methods. The new polymerization process is not only highly efficient but also scalable, allowing for the production of large quantities of the material.

Practical Applications
The material holds promise for a wide range of applications across various industries. When added to Ultem — a polymer in the same family as Kevlar — in small amounts (2.5% by weight), it significantly enhanced the overall strength and toughness of the composite material. This suggests potential use in high-performance protective textiles, such as lightweight body armor and ballistic fabrics. Beyond protective textiles, its lightweight and impact-resistant properties make it a candidate for architectural and interior applications, including durable surfaces and flexible construction materials. Additionally, its robustness and scalability offer opportunities in product and packaging design, particularly for protective barriers. The material’s combination of strength and low weight also presents potential benefits for automotive and aerospace components.

Historical Context and Future Research
This innovation builds on the foundational work of Sir Fraser Stoddart, a Northwestern University chemist who pioneered the concept of mechanical bonds in the 1980s and was awarded the Nobel Prize in Chemistry in 2016. The research team, led by William Dichtel, utilized these principles to create a material with unprecedented structural and functional capabilities. The team plans to conduct further analysis of the material’s properties and explore new applications to maximize its potential.

Source: ScienceDaily
Image: Northwestern University