Hydroxyethyl methacrylate modified polylactic acids and their micelle properties

Polylactic acid (PLA) is one of promising biocompatible and biodegradable polyester. Poly(2-hydroxyethyl methacrylate) (PHEMA) is a polymer with good hydrophilicity. The hydrophilic PHEMA may improve PLA’s amphiphilic properties. Hence, directly starting from hydroxyethyl methacrylate (HEMA), lactic acid (LA), maleic anhydride (MAH) and 2,2'-azobis(2-methyl-propionitrile) (AIBN), a series of new amphiphilic copolymers PLA₂₀MH_n were obtained through direct melt polycondensation (DMP) and subsequent free radical polymerization (FRP) in one pot. The results show that PLA₂₀MH_n can self-assemble in aqueous solution to form stable spherical micelles and dissolve hydrophobic pyrene molecules. What’s more, The CMC value can be adjusted by the polymerization ratio. Therefore, this method is expected to further realize the encapsulation and controlled release of hydrophobic drug molecules for systemic circulation in vivo.