In situ SEM studies on strain sensing mechanisms of PPy-coated electrically conducting fabrics

• Published in: Applied surface science Vol. 253; no. 7; pp. 3387 - 3392
• Main Authors: XUE, P, TAO, X. M, TSANG, H. Y
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier Science 30.01.2007
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Physics; Scanning electron microscopy; Electrically conducting fabrics; Sensitivity; Strain sensing mechanism; 07.07.Df 72 80 Le 68 35 Gv; Strains; In situ
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2006.07.003

This paper studies a flexible fabric strain sensor from PPy-coated fabrics prepared by a chemical vapor deposition method under low temperature, placing an emphasis on mechanisms of its strain sensing behavior. In situ tensile tests in a scanning electron microscope (SEM) were conducted for PPy-coated electrically conducting yarns, which were prepared by the same procedure as that for the PPy-coated fabrics, enabling it possible to observe in situ the phenomena that occurred on the fiber surface during fabric deformation. The investigation revealed that the PPy-coated nylon/polyurethane fabrics exhibited a high strain sensitivity of over 400 and very large workable strain range greater than 50%, which mainly attributes to the high conductivity and crack-opening and crack-closing mechanisms of PPy-coated polyurethane yarn, as well as the excellent properties of knitted fabric structure.