完全超疏水的 PDMS 表面用于微流控。

Completely superhydrophobic PDMS surfaces for microfluidics.

机构信息

Laboratory for MEMS Applications, IMTEK-Department of Microsystems Engineering, University of Freiburg, Georges-Koehler-Allee 103, Freiburg im Breisgau, Germany 79110.

出版信息

Langmuir. 2012 Jun 5;28(22):8292-5. doi: 10.1021/la301283m. Epub 2012 May 21.

DOI:10.1021/la301283m

PMID:22590992

Abstract

This study presents a straightforward two-step fabrication process of durable, completely superhydrophobic microchannels in PDMS. First, a composite material of PDMS/PTFE particles is prepared and used to replicate a master microstructure. Superhydrophobic surfaces are formed by subsequent plasma treatment, in which the PDMS is isotropically etched and PTFE particles are excavated. We compare the advancing and receding contact angles of intrinsic PDMS samples and composite PTFE/PDMS samples (1 wt %, 8 wt %, and 15 wt % PTFE particle concentration) and demonstrate that both the horizontal and vertical surfaces are indeed superhydrophobic. The best superhydrophobicity is observed for samples with a PTFE particle concentration of 15 wt %, which have advancing and receding contact angles of 159° ± 4° and 158° ± 3°, respectively.

摘要

本研究提出了一种简单的两步法制造工艺，可在 PDMS 中制备耐用的完全超疏水微通道。首先，制备 PDMS/PTFE 颗粒复合材料，并将其用于复制主微结构。通过后续的等离子体处理形成超疏水表面，其中 PDMS 各向同性蚀刻，PTFE 颗粒被挖掘出来。我们比较了本征 PDMS 样品和复合 PTFE/PDMS 样品（1wt%、8wt%和 15wt%PTFE 颗粒浓度）的前进和后退接触角，并证明水平和垂直表面确实具有超疏水性。在 PTFE 颗粒浓度为 15wt%的样品中观察到最佳的超疏水性，其前进和后退接触角分别为 159°±4°和 158°±3°。