Nanowerk August 24, 2022
As it is difficult to determine whether the currently used polymeric coatings applied to the surfaces of automobiles, ships, etc. to protect them from the external environment are already damaged or not, these non-reusable coatings must be regularly replaced, leading to a large amount of waste generation and high disposal costs. Researchers in South Korea have demonstrated mechanochromic and thermally reprocessable thermosets that can be used for autonomic damage reporting and self-healing coatings. A mechanochromic molecule, spiropyran (SP), was covalently incorporated into thermoreversible Diels–Alder (DA) cross-linking networks. Mechanical activation of SPs in DA networks was confirmed by computational simulations and mechanical testing. The damaged areas of the polymers changed colour, emittd fluorescence signals, and completely recovered after heat treatment. Because of the thermoreversible covalent networks, these polymers could be recycled up to fifteen times without degrading their mechanical, damage-reporting, or self-healing properties. According to the researchers their work expands the range for practical applications of force-induced chemical reactions in polymers…read more. Open Access TECHNICAL ARTICLE
Formation of thermoreversible SP-linked CANs. Credit: NPG Asia Materials volume 14, Article number: 61 (2022)Â