Synthesis of linear and star-like poly(ε-caprolactone)-b-poly{γ-2-[2-(2-methoxy-ethoxy)ethoxy]ethoxy-ε-caprolactone} amphiphilic block copolymers using zinc undecylenate

Abstract

Linear and star-like amphiphilic diblock copolymers were synthesized by the ring-opening polymerization of e-caprolactone and γ-2-[2-(2-methoxyethoxy)ethoxy]ethoxy-e-caprolactone monomers using zinc undecylenate as a catalyst. These polymers have potential applications as micellar drug delivery vehicles, therefore the properties of the linear and 4-arm star-like structures were examined in terms of their molecular weight, viscosity, thermodynamic stability, size, morphology, and drug loading capacity. Both the star-like and linear block copolymers showed good thermodynamic stability and degradability. However, the star-like polymers were shown to have increased stability at lower concentrations with a critical micelle concentration (CMC) of 5.62 × 10−4 g L−1, which is less than half the concentration of linear polymer needed to form micelles. The star-like polymeric micelles showed smaller sizes when compared with their linear counterparts and a higher drug loading capacity of doxorubicin, making them better suited for drug delivery purposes. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 3601–3608