RESISTANCE-STRAIN BEHAVIOR IN STRETCHABLE FABRIC-CARBON BLACK COMPOSITES

Abstract

Printable stretchable conductors represent one of today's cutting-edge electronic technologies with numerous emerging applications such as stretchable electronics and biosensors for use in the human body. It is their low cost, abundant material source, and ease of scalable fabrication that makes them especially attractive as an emerging technology. The thesis student whose work I build upon explored the use of carbonaceous materials as an alternative conductive coating in order to match and potentially exceed conductivity achieved in literature. She found that samples that had been infiltrated by the coating particles exhibited superior electrical performance compared to that of samples that had not been infiltrated. Particles unable to infiltrate the fabric matrix formed an aggregate layer on the exposed surface of the fabric and lose contact with one another upon minimal strain. My predecessor was unable to produce an infiltrated composite without an aggregate layer on the surface of fabric. I refine the coating protocols she used with the purpose of understanding the resistance-strain behavior of a stretchable fabric-carbon black composite without an aggregate surface coating. In determining the limits of mechanical and electrical performance, I investigate the relationship between orientation of stretch, mechanical behavior, and electrical performance. Finally, I examine how well the fabric-particle composite withstands fatigue, the tendency towards “wearing out” after repeated strain cycles. Through my analysis of both mechanical and electrical behavior from strain to failure, orientation stretch, and cycling trials, I propose a hypothesis based on interactions between individual fibers within the fabric weave as an explanation for the resistance-strain behavior exhibited by the infiltrated composite. Finally, I found that my samples exhibit good durability through repeated strain cycles. It is my hope that my work can inform future research within the field of conductive particle fabric composites.