Summary: We report a thermosensitive polypeptide consisting of hydrophilic poly(ethylene glycol)s and hydrophobic phenyl alanine ethyl esters. It is soluble in most solvents and undergoes a micelle (radius ≈ 10 nm) to nanoparticle (radius ≈ 100 nm) transition in water as the temperature increases. The transition temperature could be controlled to between 30 and 40 °C by varying the number of poly(ethylene glycol) grafts. This system might be promising for advanced drug delivery.
Measurement of the lower critical solution temperatures of PEG‐PP aqueous solutions (1.0 wt.‐%).
