Stretchable polymer composites are a new group of materials with a wide range of application possibilities in wearable electronics. The purpose of this study was to fabricate stretchable electroluminescent (EL) structures using developed polymer compositions, based on multiple different nanomaterials: luminophore nanopowders, dielectric, carbon nanotubes, and conductive platelets. The multi-layered EL structures have been printed directly on textiles using screen printing technology. During research, the appropriate rheological properties of the developed composite pastes, and their suitability for printed electronics, have been confirmed. The structure that has been created from the developed materials has been tested in terms of its mechanical strength and resistance to washing or ironing.

Rapid growth of personal electronics with concurrent research into telerehabilitation solutions discovers opportunities to redefine the future of orthopedic rehabilitation. After joint injury or operation, convalescence includes free active range of movement exercises, such as joints bending and straightening under medical supervision. Flexion detection through wearable textile sensors provides numerous potential benefits such as: (1) reduced cost; (2) continuous monitoring; (3) remote telerehabilitation; (4) gamification; and (5) detection of risk-inducing activities in daily routine. To address this issue, novel piezoresistive multi-walled carbon nanotubes/graphite/styrene–butadiene–styrene copolymer (CNT/Gr/SBS) fiber was developed. The extrusion process allowed adjustable diameter fiber production, while being a scalable, industrially adapted method of manufacturing textile electronics. Composite fibers were highly stretchable, withstanding strains up to 285%, and exhibited exceptional piezoresistive parameters with a gauge factor of 91.64 for 0–100% strain range and 2955 for the full scope. Considering the composite’s flexibility and sensitivity during a series of cyclic loading, it was concluded that developed Gr/CNT/SBS fibers were suitable for application in wearable piezoresistive sensors for telerehabilitation application.

In 2018, the European Parliament and Council laid down a directive about the promotion of the use of energy from renewable sources connected with the Paris Agreement, which sets a global ambition on climate change mitigation through deep and fast cuts in greenhouse gas emissions. Since then, the science world has been even more focused on the development of green technologies such as wind farms, waterpower stations, and photovoltaics as the European Union is preparing to shift to renewables-based energy systems. Each green power technology has its own problems and limitations. Nevertheless, for environmental protection, new power technologies have to be implemented in the near future as primary power sources. Described in this article is the application of aerosol jet printing in manufacture of photovoltaic cells, moving the technology boundaries further toward highly efficient, cost-effective, green power production. The research focused on utilizing aerosol jet printing technology to create finger-shaped collecting electrodes on a newly constructed, non-silicon photovoltaic cell, based on metal oxides. Three commercial nanosilver inks were investigated considering their printing parameters, printability on the specified substrate (AZO-coated glass, AZO-coated copper plate), resistivity of the cured composite, quality of the overprints, and application in photovoltaics. As a result, we obtained finger-shaped collecting electrodes with a resistivity of 3.5 µΩ∙cm and 8 µm width, which compares well with the literature.

Wearable electronics are new structures with a wide range of possible applications. This study aims to analyze the effects of hot pressing in thermal transfer of different carbon-based composites as a new application method of screen-printed electronics on textiles. Flexible heaters were screen-printed on polyethylene terephthalate PET foil with composites based on graphene, carbon black, and graphite with different wt.%, measured and then hot pressed to measure and analyze differences. Research showed that the hot pressing process in thermal transfer resulted in decreased electrical resistance, increased power, and higher maximal temperatures. Best results were achieved with composites based on 12 wt.% graphene with sheet resistance lowered by about 40% and increased power by about 110%. This study shows promise for thermal transfer and screen-printing combination as an alternative for creating flexible electronics on textiles.

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