It sounds a bit like science fiction.

A T-shirt that can monitor your heart rate or charge your smartphone – really?

Perhaps, yes, and in the not-too-distant future.

The reality of a digital age smart shirt came into greater focus recently thanks to researchers who discovered a way to make nylon fibers that are able to produce electricity from simple body movements.

Professor Kamal Asadi (pictured) from the University of Bath in the United Kingdom and his former student Saleem Anwar spearheaded the groundbreaking research, whose magic lies in a phenomenon called piezoelectricity, which involves mechanical energy being transferred into electric energy.

“In years to come, we could be using our T-shirts to power a device such as our mobile phone as we walk in the woods, or for monitoring our health,” Asadi said in a report from Science Daily.

Researchers said the dreamed-of shirts could incorporate electronics like sensors into the fabric. As wearers move around, they’d generate power through the fibers. The electricity could be stored in, say, a small battery that’s kept in a pocket. The battery could then be used to connect to devices.

The trick would occur thanks to the nylon fabric having piezoelectric properties. Tapping or distorting piezoelectric material generates a charge. If you add a circuit and take the charge away, the electricity can be stored and put to use.

Still, there have been big challenges to producing piezoelectric nylon materials – so big in fact that, after some interest in the 1980s, researchers essentially gave up on the idea. Then, Asadi and Anwar resumed work on the conundrum.

Going in, they knew nylon in its raw form is a white powder that can be blended with other materials, which can then be made into many different products. As Science Daily explained, “It’s when nylon is reduced to a particular crystal form that it becomes piezoelectric. The established method for creating these nylon crystals is to melt, rapidly cool and then stretch the nylon. However, this process results in thick slabs (known as ‘films’) that are piezoelectric but not suited to clothing.”

Asadi and Anwar’s first breakthrough was to take a novel approach to making piezoelectric nylon films, dissolving nylon powder in an acid solvent rather than melting it. They weren’t done yet though, as the piezoelectric qualities were prevented from activating. However, the researchers subsequently discovered that, by mixing the acid solution with acetone, they were able to dissolve the nylon and then extract the acid efficiently, leaving the nylon film in a piezoelectric phase.

Said Asadi: “The acetone bonds very strongly to the acid molecules, so when the acetone is evaporated from the nylon solution, it takes the acid with it. What you’re left with is nylon in its piezoelectric crystalline phase. The next step is to turn nylon into yarns and then integrate it into fabrics.”

Bottom line, all the sophisticated science means that professionals in the promotional products industry could one day be selling shirts that are little electric factories.

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