Preparation and properties of fluorinated amphiphilic copolymers via iron-mediated AGET ATRP

Fluorinated amphiphilic copolymers have attracted considerable attention recently due to their potential applications as well as intrinsic interest in the structures. In this paper, fluorinated amphiphilic copolymers of dodecafluoroheptyl methacrylate-poly[isobutyl methacrylate-co-(2-hydroxyethyl methacrylate)] [DFMA-P(IBMA-co-HEMA)] were prepared via activators generated by electron transfer atom transfer radical polymerization (AGET ATRP) using FeCl3·6H2O as the catalyst, vitamin C as the reducing agent, and commercially available organic acid, sulfosalicylic acid (SSA), as the ligand. To improve the amphipathy, copolymers with carboxyl groups were further obtained by esterification of hydroxyl groups in HEMA of fluorinated copolymers with maleic anhydride (MA) under mild conditions. The gel permeation chromatography data obtained verified the polymerization and showed the well controlling of Fe/SSA polymerization system. Fourier transform infrared spectroscopy and 1H nuclear magnetic resonance methods confirmed the structures of the copolymers. The contact angle measurement indicated that the water contact angles decreased gradually with the increasing of MA content. Finally transmission electron microscopy measurement showed the self-assembly behavior of the polymers. The effects of water content and ions in the solvent on the self-assembly behavior were studied in detail. These results demonstrate that the fluorinated amphiphilic polymers obtained may have applications for drug delivery systems, encapsulation, and so on.