(547l) Aqueous Benzyl Alcohol Oxidation Using Polymer Nanoreactors: Towards Multifunctional Nanoscale Reactors

Authors: 
Harrison, A., Virginia Commonwealth University
Vuong, T., Virginia Commonwealth University
Nguyen, M., Virginia Commonwealth University
Tang, C., Virginia Commonwealth University

Confining catalyzed reactions to the hydrophobic core of micellar nanoreactors can facilitate organic phase reactions in a bulk aqueous environment. We are investigating confining catalyzed reactions to the hydrophobic core of kinetically-trapped polymer nanoreactor to achieve reaction and separation by leveraging the biphasic nature of the reaction. Core-shell nanoreactors encapsulating catalytic gold nanoparticles have been fabricated through block copolymer directed self-assembly. The focus of this work was evaluating use of the nanoreactors for oxidation reactions using conversion of benzyl alcohol to benzaldehyde as a model reaction. Using polystyrene as the microenvironment two oxidants were investigated: air and hydrogen peroxide. Use of hydrogen peroxide as an oxidant resulted in a 10-fold increase in benzyl alcohol conversion compared air. We also investigated the effect of hydrophobic microenvironments on catalytic oxidation using polystyrene, vitamin E, and perflourodecalin. The presence of Vitamin E in the nanoreactor core inhibited the reaction due to its anti-oxidant properties. The presence of perfluorodecalin nanoreactors increased the conversion of benzyl alcohol compared to polystyrene by 2-fold. This improvement in conversion may be attributed to enhanced oxygen solubility. This work demonstrates the importance of oxidant transport and solubility in the nanoreactor core. We are currently investigating methods to improve stability of the nanoreactors to achieve spontaneous phase separation of the product.