A novel method of fabricating carbon nanotubes-polydimethylsiloxane composite electrodes for electrocardiography

Abstract

Polymer-based flexible electrodes are receiving much attention in medical applications due to their good wearing comfort. The current fabrication methods of such electrodes are not widely applied. In this study, polydimethylsiloxane (PDMS) and conductive additives of carbon nanotubes (CNTs) were employed to fabricate composite electrodes for electrocardiography (ECG). A three-step dispersion process consisting of ultrasonication, stirring, and in situ polymerization was developed to yield homogenous CNTs-PDMS mixtures. The CNTs-PDMS mixtures were used to fabricate CNTs-PDMS composite electrodes by replica technology. The influence of ultrasonication time and CNT concentration on polymer electrode performance was evaluated by impedance and ECG measurements. The signal amplitude of the electrodes prepared using an ultrasonication time of 12 h and CNT content of 5 wt% was comparable to that of commercial Ag/AgCl electrodes. The polymer electrodes were easily fabricated by conventional manufacturing techniques, indicating a potential advantage of reduced cost for mass production.

Nanocomposite-Based Microstructured Piezoresistive Pressure Sensors for Low-Pressure Measurement Range

“…As described in detail in the next paragraph, the preparation process of the MWCNT/PDMS involves multiple dispersion steps utilising ultrasonication, an organic solvent and mechanical stirring as in [ 38 , 39 , 40 , 41 , 42 , 43 ], to achieve a uniform distribution of the MWCNT filler particles within the elastomeric matrix and facilitate an isotropic composite conductivity. Due to the strong inter-tube Van der Waals attractive forces, CNTs form together highly aggregated agglomerates in their natural state and hence external mechanical energy is required to separate these aggregates [ 44 , 45 , 46 , 47 ].…”

Conductive and flexible multi‐walled carbon nanotube/polydimethylsiloxane composites made with naphthalene/toluene mixture

“…Recently, there have been researches on finding the optimum solvents to disperse CNTs into specific polymer matrices such as PDMS . Interestingly, Liu and Choi reported that although some of the organic solvents worked well for the dissolution of PDMS and the dispersion of MWCNTs, separately, they might not work when they were used for dispersing the MWCNTs into the PDMS solution .…”

High-Adhesive Flexible Electrodes and Their Manufacture: A Review

“…CNTs, carbon fibers (CFs), and their composites with different forms are the most commonly used materials in stretchable EP electrodes [48,49]. Liu et al mixed CNT as the conductive filler with PDMS to obtain a uniform CNTS-PDMS mixture; the signal amplitude measured by the ECG electrode manufactured using this mixture was equivalent to that of the Ag/AgCl electrode [50].…”