Light scattering and luminescence studies on self-aggregation behavior of amphiphilic copolymer micelles.
The self-aggregation behavior of three amphiphilic graft copolymers, oligo(9,9-dihexyl)fluorence-graft-poly(ethylene oxide) (OHF-g-PEO), with different architectures was studied by dynamic and static light scattering (DLS and SLS) in combination with fluorescence spectroscopy and transmission electron microscopy (TEM). The formation of self-assembled polymeric micelles was confirmed by SLS and TEM. DLS and SLS analyses showed that the architecture of graft copolymers has a dramatic effect on critical aggregation concentration (CAC), micelle size distribution, apparent aggregation number (Nagg app), and apparent molecular weight of polymer aggregates (Mw,agg app). An architecture-dependent excimer emission, resulting from the pi-pi stacking of the oligofluorene backbones, was also observed from the photoluminescence spectra of the micelle aqueous solutions, which indicated a strong intermolecular interaction among the polymeric molecules. The excimer emission was further investigated by time-resolved fluorescence spectroscopy.
D001672:Biocompatible Materials / Q000737:chemistry*; D005449:Fluorenes / Q000737:chemistry*; D049449:Luminescence; D008823:Micelles; D046529:Microscopy, Electron, Transmission; D011092:Polyethylene Glycols / Q000737:chemistry*; D012542:Scattering, Radiation; D012996:Solutions / Q000737:chemistry; D013050:Spectrometry, Fluorescence; D013499:Surface Properties; D014867:Water / Q000737:chemistry
D001672:Biocompatible Materials; D005449:Fluorenes; D008823:Micelles; D012996:Solutions; D014867:Water; D011092:Polyethylene Glycols