US Army DEVCOM | Biodegradable Polymer Replacement

Lara Prosser, Susie Richart, Jocelyn Zhu

Historically, nylon takes decades to degrade and leaves behind a legacy of microplastics which are major pollutants of water, air and ground environments. To improve sustainability, U.S. Army DEVCOM challenged our team to find a biodegradable polymer replacement for nylon to be used in a variety of their textile products.

For this project, our team investigated three biodegradable nylon options which utilize additives and other technologies to increase the biodegradation rate of the polymer. We evaluated these three polymer replacements based on their biodegradability and fabric performance using a benchmark of the preexisting standard U.S. Army fabric and continuous filament nylon woven to the same specification as the prototypes.

The yarns were placed into a biodegradation test for approximately one month, with weekly monitoring and regulation, and mechanically tested in yarn and fabric form. The samples were woven into a plain weave fabric to test their fabric performance against the nylon benchmark fabric. Extra tension had to be applied during the warping and drawing in process to combat the impact of texturing and high elastic recovery of the yarns.

In this project, our team learned how to utilize our engineering skills in troubleshooting sourcing various yarns with specifications, understanding the effect of texturing yarns for the weaving process and normalizing data so that the evaluation of the performance of each yarn would be accurate. Additionally, we learned how to use limitations, such as timeline and access to necessary resources, to create a modified biodegradability test which increased microorganism activity and provided direct visibility of the degradation process. Based on preliminary results, our team has decided that Amni Soul Eco and CiCLO enhanced nylon would be two great alternatives for the nylon in U.S. Army fabric. The mechanical properties and biodegradation of the two fibers has shown promise for future applications. We also recommend looking into fabric degradation, as we only examined yarn degradation during this project.