ICNF 2015 - 2nd International Conference on Natural Fibers
Teaching Cotton New Tricks via manipulation of Nanoscale Phenomena
Associate Professor of Fiber Science & Director of The Textiles Nanotechnology Laboratory, Cornell University in Ithaca, NY, USA
Juan P. Hinestroza is a tenured Associate Professor of Fiber Science and directs The Textiles Nanotechnology Laboratory at the College of Human Ecology of Cornell University in Ithaca, NY. Professor Hinestroza obtained a Ph.D. from the Department of Chemical and Biomolecular Engineering at Tulane University and B.Sc. in Chemical Engineering from Universidad Industrial de Santander. Prior to pursuing doctoral studies, Professor Hinestroza worked as a process control engineer for The Dow Chemical Company.
In this presentation, we will discuss examples of several strategies –based on self, forced and convective assembly techniques – that our laboratory have used to modify the properties of cotton using nanoscale materials.
In the first case we will present the assembly of functionalized nanoparticles on the surface of cotton fibers aimed at creating conformal and uniform coatings with nanoscale precision. Some of these conformal coatings exhibit enhanced antibacterial properties and can be used to create tunable structural coloration effects. As the space between particles can be tailored by controlling the functionalization of the cotton’s surface and the surface’s chemistry of the nanoparticles, unique olephobic/hydrophobic as well as highly sensitive substrates for SERS spectroscopy can be created.
In the second case we will discuss the development of electrically responsive cotton using an in-situ polymerization method capable of creating flexible bridges between nanoparticles. The resulting conductive threads could be used for simultaneously sewing and wiring wearable electronic textiles. Furthermore, the same procedure was used to create semiconductor-based nanolayers on cotton fibers and these layers were assembled into two types of cotton-based transistors – and Organic electrochemical transistor (OECT) and an organic field effect transistors (OFET). In the last case, we will discuss the use of metal-organic frameworks (MOFs) to create cotton fabrics capable of sensing and trapping toxic gases, insecticides and other value-added compounds by judiciously controlling the interactions between the MOF and the functional groups on the surface of the cotton fibers.
These examples demonstrate how an “old” natural fiber such as cotton can be used as an engineering material with unique functionalities while preserving its comfort, flexibility and water absorbency properties. The strategies developed are scalable and could be replicated in many other cellulose-based natural fibers.