Switching fluid slippage on pH-responsive superhydrophobic surfaces.
Two stimuli-responsive polymer brushes, poly(dimethylaminoethyl methacrylate) and poly(methacrylic acid), were grafted from initiator-modified anodized alumina substrates to prepare two pH-responsive surfaces. By regulating the swelling states of the two polymers, water droplets can roll off or adhere onto the textured surface because of different adhesion forces. These forces also strongly affect boundary slippage. To determine the different slippage effects of fluid on our pH-responsive surfaces, a series of rheological experiments are carried out on two kinds of surfaces. A large slip length is obtained and reversibly regulated by changing the fluid pH. These responsive superhydrophobic surfaces with considerable slip length and pH-responsive properties have extensive potential applications in intelligent micro- and nanofluidic devices or biodevices, which can solve fluid flow problems.
State Key Laboratory of Solid Lubrication, Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences , Lanzhou 730000, P. R. China.
Yang
Y
Wu
Zhilu
Z
Liu
Yongmin
Y
Liang
Xiaowei
X
Pei
Feng
F
Zhou
Qunji
Q
Xue