Nov_Dec_AMP_Digital

A D V A N C E D M A T E R I A L S & P R O C E S S E S | N O V E M B E R / D E C E M B E R 2 0 2 0 9 biocompatibility experiments on their elastomers and found both areas matched that of more traditional bio- materials used in medicine. Other pos- sible applications for the framework include industrial elastomers such as eco-friendly tires that biodegrade. cornell.edu . MEASURING POLYMER NANOFIBERS To study the yield stress of poly- mer nanofibers, scientists from the University of Illinois at Urbana-Cham- paign are using specialized micro-sized devices. Researcher Debashish Das pre- viously designed and fabricated micro- electro-mechanical systems (MEMS), which are smaller than one millimeter in size, to experiment with nanoscale fibers. The research aims to inform the design and manufacturing of products made up of random networks of fila- ments, such as robust filters designed to block foreign particles from entering our lungs. “Networks of interconnected fila- ments are everywhere in bi- ological and bioengineered systems, such as connective tissues, spider webs, and scaffolds for tissue growth, as well as consumer prod- ucts, such as air filters,” ex- plains Das. “This research provides direct experimen- tal insights into the way adhesion and friction are coupled at the nanometer length scale.” According to Das, “In this study, we coupled two MEMS devices oriented orthogonally to push two fibers together and then sep- arated them by sliding. While doing so we were able to simultaneously mea- sure the force due to adhesion and due to friction.” illinois.edu . A polymer nanofiber, smaller than one hundredth the size of a human hair, is shown mounted on a MEMS mechanical testing device with inset of two devices.