Imagine a suit of armor that was as light as cloth but stronger than steel. Made from materials linked together like molecular chain armor. Scientists may just be taking the first steps towards making this a reality.
A team of researchers led by scientists at Northwestern University has developed what may be the first two-dimensional (2D) material that is mechanically connected. This is similar to links in a chain letter. The content was detailed on January 16th. study Published in the journal scienceExtremely flexible and strong With promising applications in products such as lightweight body armor and bulletproof fabric.
Researchers create materials at the nanoscale This means that each component can be measured in nanometers. It's a technique. polymer: A substance consisting of large molecules that are themselves made up of smaller chemical units called monomers. Examples of polymers include proteins, cellulose, and nucleic acids.
2D mechanically connected materials are polymeric structures that use mechanical bonds. which is a bond that has physical coordination Opposite of covalent bonds They are normally made up of polymers and involve sharing of electrons. The material has 100 trillion mechanical bonds per 0.16 square inch (1 square centimeter), the highest density of mechanical bonds ever seen. According to the researchers
“We created an entirely new polymer structure,” said study co-author William Dichtel from Northwestern University. statement– “It is similar to chain mail in that it cannot be easily torn. Because each mechanical bond is free to move back and forth slightly, if pulled, the force can be distributed in many directions. And if you want to take it apart You have to destroy it in many places. We are continuing to explore its properties and may study it for many more years.”
The biggest challenge in creating mechanically connected molecules lies in finding ways to guide polymers to form mechanical bonds, said Madison Bardot of Northwestern University, who led the study. He is credited with inventing a new way to achieve this goal. The team placed the x-shaped monomers in the crystal structure. (a specific arrangement) and crystallize with other molecules This reaction creates mechanical bonds within the crystal. The final product is a 2D layer of interconnected polymer sheets made from these bonds between X-shaped monomers, which the researchers filled in with more X-shaped monomers.
“It is a high-risk, high-reward concept. We had to question our assumptions about what kinds of reactions are possible in molecular crystals,” says Dichtel. The resulting material is incredibly strong. But it's also flexible and easy to manage. This is because the individual interconnected molecular sheets separate when the polymer is dissolved in a solvent.
“After the polymer is created, There's not much holding the structure together,” he adds. “So when we put it in a solvent The crystals will melt, but the individual 2D layers will stick together. We can manipulate those individual sheets.”
While previous researchers have created polymers with mechanical bonds in very small quantities, they may be difficult to mass produce. But the team's new approach was surprisingly scalable. They generated more than a pound (0.5 kilogram) of material and suggested the possibility of making even more.
However, even small new polymer structures can improve other substances. The researchers created a material composed of 97.5% Ultem fibers (an extremely durable material in the same family as Kevlar) and 2.5% Polymer. 2D and concluded that the combination made the first material significantly stronger.
“We have a lot of analysis to do. But we can tell that this enhances the strength of these composites,” Dichtel continued. “Almost every property we measured was unique in some way.”
This incredibly strong and flexible material may just be the armor the future awaits.