Bottle brush star block copolymer nanoreactors for efficient photooxidation catalysis: effects of chain softness

Abstract

Photooxidation using a photosensitizer is regarded as a promising method in chemical conversion. In particular, metalloporphyrin based three dimensional polymers have garnered significant attention as potential materials for photooxidation. Herein, we have synthesized amphiphilic bottle brush star block copolymers through a core-first ring-opening metathesis polymerization (ROMP) approach to investigate the effects of polymer softness. The sequential ROMP involving a multifunctional porphyrin core and macro-monomer has allowed us to create well-defined bottle brush star block copolymers. Moreover, we have explored these bottle brush star block copolymers as catalysts for photooxidation in furfural oxidation. The exceptional softness feature of the bottle brush polymer has significantly enhanced the photocatalytic activity of these polymer catalysts. Additionally, we investigated the influence of the hydrophobic ratio within these amphiphilic block copolymers. This research underscores the critical role of molecular design in polymer catalysts and highlights the potential of bottle brush star polymers for environmental applications. The bottle brush star polymer, characterized by its super-soft nature, has the remarkable ability to accelerate the photocatalytic activity of the nanoreactor through enhanced diffusion.