A facile preparation of the superhydrophobic polydimethylsiloxane materials and its performances based on the supercritical fluid foaming

The supercritical foaming (SCF) method was proposed to conveniently fabricate superhydrophobic polydimethylsiloxane (PDMS) surface. The effect of foaming parameters on the cellular structure, wettability, mechanical properties and thermal properties was investigated. This work indicates that the microstructure plays an important role in the superhydrophobicity of the PDMS materials. When the cell size and cell wall size, respectively, reach to 103.6 and 29.7 μm, the water contact angle (WCA) of the microcellular PDMS foams can achieve the maximum value 158°, and the air occupies about 90.6% of the contact areas. Meanwhile, the tensile strength of superhydrophobic PDMS materials can reach to 0.81 MPa, indicating that the superhydrophobic PDMS materials are useful. Moreover, the superhydrophobic PDMS materials show good thermal stability and excellent adiabatic property. And the method is simple and convenient, which can be used for the preparation of the superhydrophobic surfaces.