A team of engineers has invented a remarkable new material that gets stronger after an impact. The material’s creators also say it is electrically conductive, making it an ideal candidate for wearables or other electronics that are subject to repeated stresses and impacts. Rather surprisingly, the inventors of their new material say the unique properties of corn starch, a common food additive, inspired their efforts. “When I stir cornstarch and water slowly, the spoon moves easily,” explains Yue (Jessica) Wang, a materials scientist and the project’s principal investigator. “But if I lift the spoon out and then stab the mixture,...