Water probably isn’t at the top of your list of raw materials when you think about how to make electronic components. However, researchers from the University of Tsukuba used volcanic spring water in a recent study that was published in the Journal of Water Chemistry and Technology to assist in the production of the plastic that is an essential component of numerous contemporary technologies.
Many current technologies’ electronic parts are held together by plastic. One of these plastics is called polyaniline (PANI). There are clear advantages to using the most environmentally friendly solvent for PANI because millions of square meters of it are used annually for this and other purposes. Pani can be made with a variety of solvents, but most of them are toxic and won’t work with common methods for making devices for mass production, like inkjet printing.
One option for a solvent is ethanol. In fact, the authors of this study have achieved this. According to senior author Professor Hiromasa Goto, “we recently reported using ethanol with a small amount of iodine additive for the preparation of polyaniline.” Water, on the other hand, is the most eco-friendly solvent, so it would be an even better choice.”
“We recently reported the use of ethanol with a modest amount of iodine additive for the preparation of polyaniline. Water, on the other hand, is the ultimate environmentally friendly solvent and so an even better option.”
Professor Hiromasa Goto,
Because aniline is typically transformed into pani by an oxidizer and an acid, pure water will not work. In any case, volcanic spring water contains sulfate and an overflow of mineral particles that, on a fundamental level, are adequate for polymerization. The research team set out to test this hypothesis.
The analysts arranged PANI, nanoscale PANI particles, and PANI/silk composites by just blending their combinations short-term at 0°C. They confirmed that trace minerals were not the source of the PANI’s conductivity and optimized its conductivity. Professor Goto explains, “Scanning electron microscopy indicates that each thread of a manufactured silk fabric was coated with PANI, and the shape of the fibers remained unchanged.” As a result, we have created an easy method for making textiles that can conduct electricity.
These PANI composites can be used in numerous other ways. For instance, PANI-infused filter paper was used by the researchers to get rid of nearly 75% of the trace iodine in a water sample.
One of the most environmentally friendly ways to prepare PANI was probably used in this work: in low-temperature water from a volcanic spring. Since any kind of water would be a suitable solvent for PANI synthesis, it would be simple to determine the ideal mineral concentration, pH, and sulfate concentration for this synthesis. The production of PANI for electronics may be regarded as the pinnacle of environmentally friendly chemistry because it is synthesized in a way that does not result in the waste of any oil and does not pose a flammability risk.
More information: Kyoka Komaba et al, Synthesis of Polyaniline and Polyaniline/Fiber Composites in Geothermal Water, Journal of Water Chemistry and Technology (2023). DOI: 10.3103/S1063455X23010046
