Heterogeneous polymer degradation due to photothermal heating

We are interested in observing the effects of thermally-driven chemical reactions occurring in small volumes within a solid material, where diffusion of reactants and products is limited. Such experiments can be achieved by photothermally heating metal nanoparticles incorporated within the polymer which results in significant heat generation at the particles and an inhomogeneous steady state temperature distribution within the solid material, where regions far from any particle are cool, whereas those in a particle's immediate vicinity experience temperatures of 100-200 deg. C. Polyethylcyanoacrylate (PECA) degrades by depolymerizing and in confinement, the monomer will repolymerize to form oligomers. In principle, such a process might enable internal conversion of polymer to oligomer without significant loss of mechanical properties, and thus potentially address issues such as microfragmentation of plastics in the environment. We characterize degradation of PECA:starch:nanoparticle composites via GPC, dilute solution viscometry, electron and optical microscopy, and mechanical property measurements, and compare and contrast degradation obtained via photothermal heating with that obtained by conventional means.