Fabrication of Polyethylene Superhydrophobic Surfaces by Stretching-Controlled Micromolding

This paper describes a novel process that is stretching-controlled thermal micromolding, to fabricate bionic superhydrophobic polyethylene films. Low-density polyethylene was thermally pressed in a vacuum oven onto PDMS stamps replicated from lotus leaves. After being cooled and peeled off from the stamps, the polyethylene films with I superhydrophobic surface were created, exhibiting a water contact angle of 154.1 +/- 3.5 degrees and a rolling angle of approximate to 7 degrees. SEM imaging showed that the superhydrophobic surface had micro-papillas much higher than those on the lotus leaf, demonstrating the papillas had been stretched longer from the holes on the stamp during the separating process. This study shows that micromolding is a promising technique for large scale production of superhydrophobic films, even if the holes on the mold are not deep enough.