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This article describes the development of transcutaneous nerve stimulating electrodes (TENS) by means of electrically conductive ink and conductive yarn. The scope of work covered a selection of three types of knitwear with a similar surface weight with different raw material composition. Stimulating electrodes were made by means of film printing and machine embroidery. The electrodes were verified after friction tests, washing, and mechanical deformation. Each process was followed by a check of the resistive properties and assessment of the sensations in order to evaluate their performance. Tests of the surface resistance of research materials confirmed the possibility of preparing textile electrodes for electrostimulation with the use of the film-printing technique and machine embroidery. Resistance of the electrodes made on all types of substrates ranged from approximately 1.00 × 10−2 Ω to around 2.00 × 102 Ω, while the electrodes are commercially available at the level of approximately 3.5 × 105 Ω. This paper underpins the validation of the conclusion that operational processes do not adversely affect the functioning of the developed textile electrodes.

In this article we present the results of our investigations of reduction of graphene oxide overprints, deposited by ink-jet method, by hydrobromic acid. Our study presents impact of different parameters of reduction, such as a temperature and time of the process on the chemical composition and electrical conductivity of the resulting material – reduced graphene oxide. Our results show the outstanding potential of this method for use in the production of flexible and elastic electronics and indicate the optimal parameters of reduction, which allow producing the optimal product.

The unique properties of graphene, such as the high elasticity, mechanical strength, thermal conductivity, very high electrical conductivity and transparency, make them it an interesting material for stretchable electronic applications. In the work presented herein, the authors used graphene and carbon nanotubes to introduce chemical sensing properties into textile materials by means of a screen printing method. Carbon nanotubes and graphene pellets were dispersed in water and used as a printing paste in the screen printing process. Three printing paste compositions were prepared-0%, 1% and 3% graphene pellet content with a constant 3% carbon nanotube mass content. Commercially available materials were used in this process. As a substrate, a twill woven cotton fabric was utilized. It has been found that the addition of graphene to printing paste that contains carbon nanotubes significantly enhances the electrical conductivity and sensing properties of the final product.

We evaluated a solvent vapor-sensitive, non-woven fabric made from a biodegradable, poly(lactic acid) (PLA) polymer loaded with multi-walled carbon nanotubes. The sensory properties of the fabric were obtained by optimizing the process parameters for manufacturing the melt-blown, non-woven fabric composed of 98% PLA 4060D (Nature Works) and 2% multi-walled carbon nanotubes (Nanocyl®). The diffusion of polar and non-polar solvent molecules influenced the electron flow between the separated carbon nanotubes in percolation paths built into the PLA, resulting in an increase of the resistance of the melt-blown, non-woven fabrics. The statistically significant differences between the mean values of electrical resistance before and after the influence of the tested solvent vapors were achieved for the non-woven fabrics manufactured at high air velocity and low extruder screw speed, taking the values of 30 m3/h and 20 rpm, respectively. The results obtained for the non-woven fabric manufactured in the optimal conditions show that methanol vapor response has the lowest amplitude of 15%, whereas for benzene, acetone and toluene sensitivity reaches values of 60%, 40%, and 35%, respectively. The values of the relative resistance amplitude correspond with Flory–Huggins interaction parameters κPLA\benzene PLA\acetone PLA\toluene PLA\methanol.

The main aim of this research was to detail the use of melt-blown technology to manufacture a temperature-sensitive nonwoven fabric. The sensor properties of the fabric were achieved by application of the optimal composition of immiscible polymer blends loaded with multiwall carbon nanotubes (MWCNTs). As the sensing phase, a dispersion of MWCNTs in poly(e-caprolactone) (PCL) was used. The sensing phase was blended with a matrix made of polypropylene (PP). Three different polymer compositions were subjected to the melt-blowing process, changing the proportion of the matrix polymer to the dispersed phase to the range of 50–70% and changing the MWCNTs content to be between 1.2 and 2%. The selection of technological parameters was based on the thermal characteristics of the polymers used. Nonwoven fabrics made of these composites were characterized by measuring their electrical properties as a function of external stimuli. In particular, their responses to cycle changing of temperature in a range of 20–80°C were monitored. The 70%PP/28.8%/1.2%MWCNT nonwoven fabrics were observed to show the best sensitivity to changes in temperature between 50 and 60°C. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

The characteristic properties of carbon nanotubes (CNTs), particularly their heat conduction, electrical conductivity, high modulus of elasticity, high strength, and resistance to chemicals, have resulted in widespread application of CNTs in nanotechnologies. In this study, CNTs were used to impart specific functionality to textiles by printing techniques. To this aim, modified commercial aqueous dispersions of multiwalled CNTs from Nanocyl® were used for preparing special compositions as paste for printing by conventional techniques (screen printing) and as inks for ink-jet printing to bestow the fabric antistatic and antibacterial properties. Taking into account the importance of the dispersion level of CNT in the printing composition from the point of view of antistatic properties, the quality of the CNT dispersion was assessed on the basis of particle size distribution by means of a DLS PSS Nicomp device. Printings were done on two types of woven fabrics: 100% cotton and 30/70% cotton/polyester blend. The CNTs used in printing were found to impart antistatic and antibacterial properties to the printed fabrics. These imparted properties were resistant to repeated washing. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Graphene, because of its exceptional properties such as very good electrical conductance, flexibility and high optical transparency in visible light spectrum, has proved to be an excellent nanomaterial for modern electronic applications. The natural point of view is to use this new nanomaterial for the development of unique textronic devices such as sensory systems for monitoring human body’s vital functions and atmospheric composition. The present review shows the state of art of materials science and possibilities of the smart textiles design with graphene. The most promising applications of graphene for the design of textronic devices are the development of conductive polymer composites (CPC) and the development of inks and pastes for printing conductive tracks on textile materials. The preliminary results of implementation of 2D carbon structure into textronic devices are presented.

The overprints produced in inkjet technology with graphene oxide dispersion are presented. The graphene oxide ink is developed to be fully compatible with standard industrial printers and polyester substrates. Post-printing chemical reduction procedure is proposed, which leads to the restoration of electrical conductivity without destroying the substrate. The presented results show the outstanding potential of graphene oxide for rapid and cost efficient commercial implementation to production of flexible electronics. Properties of graphene-based electrodes are characterized on the macro- and nano-scale. The observed nano-scale inhomogeneity of overprints' conductivity is found to be essential in the field of future industrial applications.