Researchers at the Massachusetts Institute of Technology have made a significant breakthrough in developing new "metamaterials" that boast both strength and elasticity, a feat that has long eluded engineers in the materials science field, as robust materials typically lack flexibility. According to a detailed account by MIT News, the novel material, which can stretch over four times its initial size without breaking, presents a unique combination of rigid components embedded within a softer and more pliable structure. MIT's approach contrasts with the norm of focusing solely on maximizing strength; it proposes a balance that could revolutionize potential applications ranging from durable textiles to flexible semiconductors.
Made using a polymer akin to plexiglass, known for its brittleness, the material's resilience stems from its intricate design—a mesh of tiny struts and springs—printed in unison through a high-resolution, laser-based technique known as two-photon lithography, the process permits the metamaterial to endure stretching to three times its original length and is ten times more stretch-tolerant compared to traditional lattice-patterned materials made from the same substance, Carlos Portela, the Robert N. Noyce Career Development Associate Professor at MIT, explained the process involves a mess of spaghetti tangled around a lattice, which, when stressed, promotes more entanglements and therefore more energy dissipation within the structure.
This emergent technology stands to benefit various sectors, with prospects for creating semi-flexible strong ceramics, glass, and even metals, as Portela noted to MIT News. The engineering team has further ambitions to incorporate temperature-responsive polymers that adapt their flexibility and porosity in response to environmental stimuli, opening doors to smart fabrics that react to changes in the weather or potentially wearable tech that adjusts to body heat.
James Utama Surjadi, the study's first author, expressed surprise at the impact of intentional defects within the material, which, counterintuitively, enhanced its stretchability and energy absorption, "once we started adding defects, we doubled the amount of stretch we were able to do and tripled the amount of energy that we dissipated," Surjadi told MIT News. Joined by fellow co-authors Bastien Aymon and Molly Carton, the team continues to refine their computational models to predict how different blends of stiffness and stretchiness will perform, envisioning significant improvements in the durability and adaptability of everyday materials.
Funds from the U.S. National Science Foundation and the MIT MechE MathWorks Seed Fund have supported this research, which was enabled by utilizing facilities including MIT.nano's expansive technology labs. The findings, which could pave the way for tougher yet more adaptable materials, were announced in the prestigious journal Nature Materials, signaling an important milestone for the team and the broader field of material science.
