温度応答型ミセルを形成するジブロックコポリマーのリビングカチオン重合による合成
2005 年 62 巻 2 号 p. 87-91
詳細
2005 年 62 巻 2 号 p. 87-91
Thermosensitive diblock copolymers with a hydrophobic segment were prepared by sequential living cationic polymerization using Et1.5AlCl1.5 in the presence of an added base in toluene at 0°C. These diblock copolymers formed a micelle in water with a core of hydrophobic segments and a corona of LCST-type thermosensitive segments, which was confirmed by dynamic light scattering and 1H NMR measurements. The resulting micellar aqueous solutions showed highly sensitive phase separation upon heating due to the dehydration of the corona segments. The phase separation temperature of a micelle was controlled by regulating chain length, composition, and the pendant structures of a core and/or a corona segment in a diblock copolymer. The narrow molecular weight distribution of constituent diblock copolymers has been shown to be indispensable for achieving sharp phase separation.
