Billions of dollars of annual economic activity is lost due to the solar UV degradation of polymeric systems in the industrial, commercial, and household sphere. UV induces polymeric degradation in most cases through the generation of radicals that feed extensive and formulation-specific chains of secondary reactions. Complete modeling of these reaction chains is intellectually and computationally intensive. A simpler model for systems before network formation is proposed based on the assumption that only two classes of radical reactions affect the molecular weight distributions (MWD) in pure polymers: macroradical scission and macroradical recombination. The model subsumes all kinetic details into a few experimentally determined parameters and can theoretically be applied in a material-agnostic manner to any polymeric system.  The model predicts the full MWD and its changes with irradiation time. In this work we validate the model in the early stages of thin film reactions. The scission and recombination reactions are controlled in order to affect the MWD changes.

Modeling UV irradiation induced scission and recombination reactions in polymers with experimental verification

248th National Meeting (2014)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.