Controlled Disassembly of Poly(methyl acrylate) Microparticle-Based Polymers using Ethanol-Water Mixtures.

Understanding and controlling the degradation conditions of polymers is essential to achieve an environmentally friendly recycling of polymeric materials without deterioration. In this study, we investigated the disassembly of microparticle-based polymer films into the individual microconstituents under mild conditions such as low temperature and aqueous solutions of ethanol. The solvation of the microparticles and the microparticle-assembled structures are key factors for controlling the disassembly of microparticle-based polymers without performing chemical reactions. In particular, according to light-scattering results and molecular-dynamics calculations, the disassembly can be achieved and accelerated under specific conditions including the optimal volume fraction of the aqueous solutions of ethanol as a good solvent for the microparticles. In addition, the disassembly was studied on samples subjected to thermal annealing, which led to changes in the nanostructures of the microparticle-based polymers, as revealed by small-angle X-ray scattering and atomic-force microscopy. The obtained results demonstrate that our microparticle-based concept provides a promising platform for closed-loop materials recycling that can be expected to contribute to alleviating the environmental problems associated with the excessive use of polymeric materials.