| 초록 |
Gradient PHEMA brush was prepared on the Si wafer by microfluid system. The surface initiator, ((2-bromo, 2-methyl)propionyloxy)undecyltrichlorosilane (BUC), was synthesized for Atom Transfer Radical Polymerization (ATRP) method. And initiator was densely tethered on the Si wafer by SAM method. The SAM of initiator was investigated by change of contact angle of Si wafer and XPS. For ATRP system, Cu(II)/bipyridine and Cu(I)/bipyridine catalysts were used. The solution of HEMA and Cupper complex catalysts and water was degassed and mixed by free-and-thaw method and this solution was flown through SAM of Si wafer covered with pre-designed PDMS microchannel using syringe pump. The injection part of microchannel had thicker polymer brush than exit part of microchannel because of different reaction time. The preparation of gradient PHEMA brush was characterized by ellipsometry, AFM, contact angle, and ATR. |
