The body armor industry is constantly upgrading and reevaluating itself, in terms of physical materials, design, coverage, and countless other features. Frequent advancements in weapons manufacturing requires body armor companies to match, or even anticipate, the levels of damage that could incur. In a groundbreaking achievement, a research team at Northwestern University in Illinois has engineered a novel two-dimensional (2D) mechanically interlocking polymer, mimicking chainmail. BodyArmorNews had the pleasure of speaking with Madison Bardot, first author of the publication and PhD candidate, about the research process and impressions of the findings. This innovative material exhibits exceptional strength and flexibility, positioning it as a promising candidate for the next generation of lightweight, high-performance body armor.
Revolutionizing Polymer Structures
Traditionally, creating polymers with mechanical bonds posed significant challenges. Bardot explained that one of the main reasons for these difficulties was due to the fact that much of the existing literature relied on complicated starting materials. “We’re not a synthesis lab, so I had the idea but I had no idea how to approach it. I knew I liked crystals, so I decided to take a week off of thinking about the idea and just read the crystal literature.”
During this time off, Bardot was inspired by an article in which researchers crystalized a monomer in alternating fashion. Bardot said, “I thought I could cross link that and make it a 2D polymer, and that’s what we ended up doing.” When she proposed the idea to her supervisor William R. Dichtel, he was supportive of her pursuit but wary at the scope of the project. He is, however, cited in the Northwestern publication as giving Bardot all of the credit for the concept, bringing the high-risk high-reward idea to fruition.
Difficulties with Crystallization Techniques
The project in its entirety took upwards a year and a half. Initially when trying to reproduce the crystallization from their cited literature, they ultimately created a different crystal structure using an alternative technique. This made reactions more predictable.
When asked what the most challenging aspect of the research was, Bardot shed light on the importance of reassessing previous knowledge. “Turns out we had done it [created the polymer] a lot earlier, we just didn’t realize it,” Bardot said. “We thought if we made a 2D polymer that was that big, there was no way it would dissolve.”
Scalability and Potential Applications
When integrated into high-performance polymers like Kevlar and ULTEM, the chainmail polymer has been found to exceed expectations in enhancement. Looking into the crystallinity of the polymer, it’s been shown to melt, being stable until 450 degrees Celsius. This is unlike other performance-enhancing polymers, many of which fall apart at such high temperatures.
“I think that we can really tailor this material to different applications,” asserts Bardot, when asked about the scalability. “It definitely can operate at room temperature to increase the properties of the body armor fibers like Kevlar and ULTEM, but we’re hoping to be able to melt and use it for things like coatings.” Time in the lab and continued research will continue to provide knowledge about its properties, especially regarding changes that occur under various processes. This team has already looked at how the polymer reacts under hydrolysis, and is devoting time to understanding the silicon content by adding acid in a specialized method.
Because of its similarity to chainmail, the polymer configuration promotes the diffusion of applied force into multiple directions, which furthers its tear-resistant qualities. While the structure boasts robustness, it also brags flexibility, one of the largest necessities in the body armor commercial business. It is early days for this polymer, with many hours in the lab still necessary for further understanding. However, the polymer and its heat-compatible qualities show promising potential in the future of protective wear.
