A Study of Electric Field-Assisted Direct Ink Writing with Conducting Polymers for Electronic Textiles (E-textiles)

University Of Illinois At Chicago, Chicago IL

Investigators

Abstract

This grant supports research that contributes new knowledge related to an electronic textile manufacturing process, promoting the progress of science, advancing national prosperity, and potentially securing the national defense. Electronic textiles or e-textiles are fabrics that can conduct electricity. E-textiles enable smart systems that are capable of sensing, heating, lighting, or transmitting data. E-textile applications include muscular activity monitoring for sports and fitness, data transmission for consumers or military, sensing for space exploration, and even pathogen detection for medical treatments. The most common approach for fabricating e-textiles is to first fabricate conductive filaments and then knit or weave the filaments into fabrics. Another common e-textile manufacturing approach is to first fabricate conductive films and strips with desired geometries, and then laminate them on fabrics using adhesives or hot pressing. Despite recent advances, these existing manufacturing processes involve multiple steps and platforms, thus are usually tedious, slow, and have limited resolution and geometric complexity. This award supports fundamental research to provide the needed knowledge for developing a rapid e-textile manufacturing technology which directly prints highly conducting inks on fabric and textile. This project supports efforts to establish United States international leadership in smart textile manufacturing. The project meets the educational needs, especially, of under-represented minority groups in the Chicago area and elsewhere, by engaging and training students from all levels, K-12 to graduate, and encouraging their participation. The objective of this project is to understand the critical physics and mechanisms for printing conducting polymer inks on non-conducting textiles, such as cloth, using an electric field-assisted Direct Ink Writing (eDIW) process. Three hypotheses are tested: (1) the electrode configuration in eDIW generates a Coulomb force that affects the ink extrusion profile along the z-axis and also the ink wetting on the substrate (xy plane), allowing faster and micron-scale resolution printing of conducting polymers on rough fabrics; (2) the process fabricates conducting traces and circuits on textiles with a unique morphology, which is characterized by highly-branched and interconnected networks; and (3) such unique morphology enhances in-plane electrical conductivity of the printed e-textile. Both theoretical modeling and experiments are performed to establish a comprehensive understanding of the eDIW manufacturing system, process, and the electrical conduction mechanism of the printed traces. New knowledge is generated at the intersection of electrohydrodynamics, materials science, machine design, and manufacturing fields, advancing a huge leap in direct printing and e-textile technologies. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.