Novel Biodegradable Heterografted Polymer Brushes Prepared via a Chemoenzymatic Approach

Biodegradable heterografted molecular bottle brushes were prepared in two steps starting with a linear polyglycidol as a macroinitiator. First, ca. 45% of the polyglycidol hydroxy groups were grafted with ε‐caprolactone via enzymatic catalysis. Selective end capping of the hydroxy groups at the graft ends was achieved via enzymatic esterification with vinyl acetate or vinyl acrylate. Finally, poly(L‐lactide) grafts were attached to the remaining polyglycidol hydroxy groups by chemically catalyzed ring‐opening polymerization. The successful synthesis of the heterografted comb‐shaped brushes was confirmed by NMR and SEC analyses. Additionally, the feasibility of microsphere formulation was described. magnified image