Light triggered self-healing of polyacrylate polymers crosslinked with 7-methacryloyoxycoumarin crosslinker

Abstract

A new light-responsive crosslinker containing a coumarin photosensitive unit has been synthesised and was used in reactions with a range of acrylate monomers (butylmethyl acrylate (BMA), methyl acrylate (MA), hexyl methacrylate (HMA) and ethyl acrylate (EA)) to form crosslinked polyacrylates. The self healing ability of the resulting polymeric networks was determined by observing the visual disappearance of surface scratches on thin films due to the application of UV light only, or in some cases UV light accompanied by heating. Hardness tests were used as a measure of the mechanical properties of the cross-linked polymer films, both before and after healing.