Oxa-perfluoroalkyl end-capped PEG-based amphiphilic fluorocarbon polymer: synthesis and self-assembly behavior in water

Oxy-perfluoroalkylated end-capped polyethylene glycol (PEG) was synthesized by the reaction of PEG and polyethylene glycol monomethylether (PEG(MeO)) with trimer of hexafluoropropylene oxide (HFPO). The structures of the fluorinated polymers were characterized by ¹H NMR, ¹⁹F NMR and FTIR. Their surface activities study shows that the fluorinated polymers have high surface activity. Core-shell micellization of the fluorinated polymers was inferred from the ¹⁹F NMR spectra derived in two different solvent environments (CDCl₃ and D₂O). Their self-assembly behaviors in water were studied in detail by pyrene fluorescence techniques, dynamic light scattering and scan electron microscopy. The results demonstrated that due to different fluorine content PEGF with two end-capped fluorocarbon groups can form large aggregates with the diameter size of about 132 nm, whereas PEG(MeO)F with only one-end-capped fluorocarbon groups forms small micelles with the size of round 12 nm.