No need to throw away an old raincoat because a tiny rip or hole. Scandinavian researchers are fabricating a textile coating that automatically seals tears on the surface of waterproof workwear. Developed for EU project Safe@Sea, which is conceiving a new generation of “intelligent” clothing to protect professional fishermen, the technology shows promise even in its early stages. “We have shown that the principle works,” says Susie Jahren, a senior research scientist at SINTEF. “Holes and tears we have made in test pieces in the lab close up all on their own.”
SAFER AT SEA
Modern rainwear typically comprises a protective layer of plastic polyurethane, which is applied in liquid form to the fabric surface and allowed to harden. To achieve the self-healing effect, SINTEF researchers added microcapsules containing a glue-like substance. If the coating snags, the capsules burst to release the sealants within, filling in gaps and hardening in contact with air and water.
If the coating snags, microcapsules burst to release the sealants that harden in contact with air and water.
Although scientists in other parts of the world have created self-repairing plastics that protect metals from corrosion, particularly in the automotive industry, a textile that heals itself is still a novel idea. The adhesion could still use some work, but Jahren and her team are testing different types of bonding agents to maximize the effectiveness and strength of the microcapsules. “We still don’t know what will happen if the tears are more than a couple of millimeters long, or whether rain will wash away the glue,” Jahren adds.
Safe@Sea is an eight-member European group that is fostering a range of fishermen’s workwear with inbuilt lifesaving electronics. Other innovations currently in the pipeline include garments with integrated flotation functions and a “man overboard” button that sets off an alarm in the event of an accident.