title: Novel Electrically Conductive Porous PDMS/Carbon Nanofiber Composites for Deformable Strain Sensors and Conductors.
abstract: Highly flexible and deformable electrically conductive materials are vital for the emerging field of wearable electronics. To address the challenge of flexible materials with a relatively high electrical conductivity and a high elastic limit, we report a new and facile method to prepare porous polydimethylsiloxane/carbon nanofiber composites (denoted by p-PDMS/CNF). This method involves using sugar particles coated with carbon nanofibers (CNFs) as the templates. The resulting three-dimensional porous nanocomposites, with the CNFs embedded in the PDMS pore walls, exhibit a greatly increased failure strain (up to ∼94%) compared to that of the solid, neat PDMS (∼48%). The piezoresistive response observed under cyclic tension indicates that the unique microstructure provides the new nanocomposites with excellent durability. The electrical conductivity and the gauge factor of this new nanocomposite can be tuned by changing the content of the CNFs. The electrical conductivity increases, while the gauge factor decreases, upon increasing the content of CNFs. The gauge factor of the newly developed sensors can be adjusted from approximately 1.0 to 6.5, and the nanocomposites show stable piezoresistive performance with fast response time and good linearity in ln(R/R0) versus ln(L/L0) up to ∼70% strain. The tunable sensitivity and conductivity endow these highly stretchable nanocomposites with considerable potential for use as flexible strain sensors for monitoring the movement of human joints (where a relatively high gauge factor is needed) and also as flexible conductors for wearable electronics (where a relatively low gauge factor is required).
authors.affiliation: Sir Lawrence Wackett Aerospace Research Centre, School of Engineering, RMIT University , GPO Box 2476, Melbourne, VIC 3001, Australia.|School of Mechanical and Manufacturing Engineering, University of New South Wales , Sydney, NSW 2052, Australia.
authors.forename: Shuying
authors.identifier: http://orcid.org/0000-0002-6585-8898
authors.initials: S
authors.lastname: Wu
authors.affiliation: Australian Future Fibers Research and Innovation Centre, Institute for Frontier Materials, Deakin University , Burwood, VIC 3220, Australia.
authors.forename: Jin
authors.initials: J
authors.lastname: Zhang
authors.affiliation: Sir Lawrence Wackett Aerospace Research Centre, School of Engineering, RMIT University , GPO Box 2476, Melbourne, VIC 3001, Australia.
authors.forename: Raj B
authors.initials: RB
authors.lastname: Ladani
authors.affiliation: Sir Lawrence Wackett Aerospace Research Centre, School of Engineering, RMIT University , GPO Box 2476, Melbourne, VIC 3001, Australia.
authors.forename: Anil R
authors.initials: AR
authors.lastname: Ravindran
authors.affiliation: Sir Lawrence Wackett Aerospace Research Centre, School of Engineering, RMIT University , GPO Box 2476, Melbourne, VIC 3001, Australia.
authors.forename: Adrian P
authors.initials: AP
authors.lastname: Mouritz
authors.affiliation: Department of Mechanical Engineering, Imperial College London , London SW7 2BX, U.K.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Kinloch
authors.affiliation: School of Mechanical and Manufacturing Engineering, University of New South Wales , Sydney, NSW 2052, Australia.
authors.forename: Chun H
authors.initials: CH
authors.lastname: Wang
keywords: carbon nanofibers; conductor; piezoresistivity; polydimethylsiloxane; porous nanocomposites; strain sensor; stretchable