The hydrophobicity of film surfaces can be enhanced by introducing wrinkling and buckling, and the wrinkling method in this study is a facile way to induce various microstructures including wrinkles and buckles in film surfaces. When buckles formed, the water contact angle parallel to the wrinkled direction (θ_//) changed dramatically with strain, but the contact angle perpendicular to the wrinkled direction did not change much. It was found that the buckle structural feature was the key characteristics affecting the change in contact angle, θ_//. A dimensionless number, the ratio of buckle height to spacing (H_b/S_b) was introduced to determine the relationship between the structural feature and the contact angle, θ_//. The contact angle, θ_// strongly depended on H_b/S_b. The thickest film (h_f = 605 nm) at the highest strain (ɛ = 30%) and the highest H_b/S_b formed many large buckles, and exhibited super-hydrophobicity (θ_// = 169 ± 10°).

薄膜表面的疏水性可通过引入起皱和屈曲来增强，并且本研究中的起皱方法是在薄膜表面上引发各种微结构（包括皱纹和褶皱）的简便方法。当形成褶皱时，平行于褶皱方向的水接触角（θ _//）随应变而急剧变化，但是垂直于褶皱方向的接触角变化不大。结果发现，扣结构特征是影响接触角θ _//变化的关键特征。无量纲数，扣环高度与间距之比（H _b / S _b引入）确定结构特征和接触角θ _//之间的关系。接触角θ _//强烈取决于H _b / S _b。在最高应变（ɛ= 30％）和最高H _b / S _b的最厚膜（h _f = 605 nm）形成许多大的弯曲，并表现出超疏水性（θ _// = 169±10°）。