Researchers in China develop cheaper method for making superlyophobic surfaces
Superlyophobic surfaces (SLS) are simultaneously repellant for almost any liquid and exhibit high contact angles and low flow resist. These surface have been attracting much research interest due to the broad applications in various liquid-related applications.
They are different from superhydrophobic surfaces (SHS) that mimic the self-cleaning effect of lotus leaves, which have air trapped in the micro/nano structures decorated with low-surface-energy chemicals. In comparison, SLS requires more delicate overhang micro/nano structures to overhang on such as T-shape, inverse trapezoid and sphere, which are only achieved on very limited materials. The demanding and usually expensive fabrication remains a bottleneck for further development of SLS.
Researchers from of Shenzhen Institutes of Advanced Technology (SIAT) of the Chinese Academy of Sciences have proposed a facile and inexpensive microfabrication method to address this issue. They used poly(dimethylsiloxane) (PDMS) as the intermediate soft mold, and transferred the T-shape microstructures from two kinds of masters which are based on silicon (Si) and photoresist to various curable materials, including glass resin, poly(methyl methacrylate) (PMMA) and PDMS.
The as-fabricated polymer SLS replicas exhibit high structure fidelity, comparable non-wettability and excellent reproducibility for both water and oil during the 10-by-10 replication and possesses new features such as tunable transparency. The proposed approach decouples the material and process dependence, greatly dilutes the fabrication cost and enables high-performance SLS on a wide range of materials, which may initialize the broad applications for low-contamination, low-adhesion and self-cleaning requirements in academy, industry and daily life.
The research results have been recently published on Journal of Materials Chemistry A (2014), financially supported from National Natural Science Foundation of China. The research group is led by Prof. WU Tianzhun who has been working on micro electromechanical systems (MEMS), microfluidics and micro/nano materials. Relevant publications on SLS includes the comprehensive design, fabrication and modeling of SLS on journals including Sensors and Actuators B: Chemical (2011), Lab on a Chip (2011), and Journal of Adhesion Science and Technology (2012).
Source: Chinese Academy of Sciences