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An amphiphilic hyperbranched poly(aryl ether ketone)- graft-poly(ethylene glycol) (HPAEK- graft-PEG) rod–coil copolymer was synthesized by grafting linear PEG onto hydroxyl-terminated HPAEK (OH-HPAEK). The molecular structure, the number-average molecular weight and the thermal properties of HPAEK- graft-PEG were characterized by proton nuclear magnetic resonance and Fourier transform infrared spectroscopies, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis, respectively. The self-assembly behaviors of HPAEK- graft-PEG in the mixed solvents were investigated by transmission electron microscopy and scanning electron microscopy. The results demonstrated that the selective solvent in the used mixed solvents exerted remarkable influence on the morphology of the resulting micelles. When the mixed solvents were water/tetrahydrofuran (THF), trichloromethane/THF, and toluene/THF, that is, with the decrease of the selective solvents in polarity, HPAEK- graft-PEG could self-assemble into the regular microspheres with obvious core–shell structure, the similar quadrilateral-shaped micelles with the dimension of about 20 nm and the large complicated clew-shaped micelles, as well as the irregular large compound micelles, respectively. It is worth mentioning that the similar quadrilateral-shaped micelles were different from the toroidal micelles reported already, which had relatively obvious “angle”. The phenomenon may be ascribed that the rigid characteristic of rod HAPEK segment was conducive to the maintenance of the metastable state.

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An amphiphilic hyperbranched rod-coil copolymer was synthesized by grafting linear poly (ethylene glycol) (PEG) onto hydroxyl-terminated hyperbranched poly (aryl ether ketone) (OH-HPAEK). The molecular structure, the number-average molecular weight and the thermal properties of HPAEK- block-PEG were confirmed and characterized using proton nuclear magnetic resonance, Fourier transform infrared spectroscopy, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis, respectively. The microspheres of HPAEK- block-PEG were fabricated by the method of self-assembly, and the morphology and diameter of the obtained microspheres were characterized using transmission electron microscopy, scanning electron microscopy, and dynamic light scattering. The heat-treated experimental results demonstrated that the polymer microspheres possessed excellent thermal property that could stably exist even if heated at 130°C for 10 h. In addition, the diameter of the microspheres can be easily controlled by just adjusting the concentration of the copolymer.

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