Preparation of Cross-Linked Micelles from Glycidyl Methacrylate Based Block Copolymers and Their Usages as Nanoreactors in the Preparation of Gold Nanoparticles

This study reports the synthesis of poly(ethylene glycol)methyl ether-block-poly(glycidyl methacrylate) (MPEG-b-PGMA) diblock, and poly(ethylene glycol)methyl ether-block-poly(glycidyl methacrylate)-block-poly(methyl methacrylate) (MPEG-b-PGMA-b-PMMA) triblock copolymers via atom transfer radical polymerization and their self-assembly behaviors in aqueous media by using acetone as cosolvent. These block copolymers formed near monodisperse core-shell micelles having cross-linkable cores. Two types of cross-linked micelles, namely spherical MPEG-b-PGMA core cross-linked (CCL) micelles and MPEG-b-PGMA-b-PMMA interlayer cross-linked (ILCL) micelles, were also successfully prepared from these block copolymers by using various bifunctional cross-linkers such as hexamethylenediamine (HMDA), ethylenediamine (EDA), and 2-aminoethanethiol (AET). Cross-linking was successfully carried out via ring-opening reactions of epoxy residues of hydrophobic-cores with primary amine or thiol groups of bifunctional cross-linkers. Finally, these cross-linked micelles were successfully used as nanoreactors in the synthesis of gold nanoparticles (AuNPs) in aqueous media. Both CCL and ILCL micelles were found to be good stabilizers for AuNPs in aqueous media. Both CCL- and ILCL-stabilized AuNP dispersions were stable for a long time without any size changes and flocculation at room temperature. These cross-linked stabilized AuNPs exhibited good catalytic activities in the reduction of p-nitrophenol. (c) 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 514-526.