Stabilization of polymeric micelles with a mixed poly(ethylene oxide)/poly(2-hydroxyethyl methacrylate) shell by formation of poly(pentaerythritol tetraacrylate) nanonetworks within the micelles

Abstract

Polymeric micelles comprising a mixed poly(ethylene oxide) (PEO)/poly(2-hydroxyethyl methacrylate) (PHEMA) shell and a thermosensitive poly(propylene oxide) (PPO) core were prepared in aqueous media and stabilized by UV-induced free radical polymerization of pentaerythritol tetraacrylate (PETA). The micelles were formed from PEO₇₅PPO₃₀PEO₇₅ and PHEMA₁₅PPO₃₃PHEMA₁₅ triblock copolymers mixed at different weight ratios. The micellar morphology in aqueous solution at different concentrations, ultrasonic irradiation, and in methanol was investigated by dynamic light scattering and scanning force microscopy. The results indicate that the stabilized polymeric micelles with a mixed shell maintain their morphology under different conditions emphasizing the efficiency of the stabilizing method employed.