The wetting properties of superhydrophobic surfaces have received worldwide and tremendous attention [1] since the dual hierarchical structure of the lotus leaf was discovered [2]. Lotus-Leaf-like superhydrophobic surfaces, exhibit an amazing property for not only being wetted by water leading to a self-cleaning effect [3], but also for their great advantages in applications. In recent years, superhydrophobic surfaces are widely used in the human body implant materials [4], microfluidic tools [5], Calix azacrown [6], tunable optical lenses [7], labon-chip systems [8]. The wettability of the surface is influenced by its chemical composition and morphology [9], because chemical composition determines the surface free energy, and a lower surface energy leads to higher hydrophobicity. Additionally, the hierarchical structure (micro roughness covered with nano roughness) was not only necessary for a high contact angle (CA) but essential for the stability of the water-solid and water-air interfaces [10] Received 1 January 2014; accepted in revised form 1 April 2014Abstract. A dual-switchable surface between hydrophobic and superhydrophobic has been fabricated successfully by combining reversible addition-fragmentation chain transfer polymerization (RAFT) polymeric technology and thiol-NCO click chemistry. Well-defined block copolymer, poly(7-(6-(acryloyloxy) hexyloxy) coumarin)-b-poly(N-Isopropylacryl amide), was synthesized by RAFT, and then the block copolymer was grafted onto the surface of SiO 2 modified by toluene disocynate (TDI) via thiol-NCO click chemistry. The results of nuclear magnetic resonance (NMR) and Fourier Transform Infrared (FTIR) spectroscopies confirmed that the block copolymer (Number average molecular weight (M n ) = 9400, polydispersity index (PDI) = 1.22) has been synthesized successfully. The static contact angle (CA) of the surface prepared by SiO 2 /P (7-6-AC)-b-PNIPAAm switches from 98±2 to 137±2° by adjusting the temperature. Furthermore, the contact angle can also oscillate between 137±2 and 157±2° on the irradiation of UV light at 365 and 254 nm, respectively. The dual-switchable surfaces exhibit high stability between hydrophilicity and superhydrophobicity. Therefore, the method provides a new method to fabricate the dual-stimuli-responsive surface with tunable wettability, reversible switching, and also be easily extended to other dual-responsive surfaces. This ability to control the wettability by the adjustment of the temperature and UV light has applications in a broad range of fields.

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