Water Soluble Reversible Photocrosslinking Polymer Dielectrics.

Effective recycling of mixed materials requires the separation of the different components without the need for toxic solvents. One approach involves utilizing a water soluble coating with reversible photocrosslinkers making it robust until end of life where it can then be dissolved in water after decrosslinking. In this report, we report a novel coumarin methacrylate monomer (COUMA) and its nitroxide mediated copolymerization to create poly((methacrylic acid)-co-(styrene sulfonate)-co-(coumarin methacrylate)) (P(MAA-co-NaSS-co-COUMA)) for water-soluble thin films. Under exposure to light, the coumarin functional groups produces reversible [2+2] cycloadditions which crosslink the resulting polymer films making them no longer water soluble. Characterization of reversible crosslinking behaviour was reported through changes in contact angle and in-situ rheological characterization. The resulting polymers were successfully integrated into in metal-insulator-metal (MIM) capacitors, demonstrating the potential use for water soluble reversible photocrosslinkable dielectric materials for organic electronics. This article is protected by copyright. All rights reserved.