February 13, 2024 | Tanja Eder, Andreas Mautner, Yufeng Xu, Michael R. Reithofer, Alexander Bismarck, and Jia Min Chin
This study explores the development of transparent polydimethylsiloxane (PDMS) surfaces with covalently attached lubricants (SOCALs) to enhance anti-adhesion performance. The researchers address the challenges of activating and functionalizing hydrophobic PDMS, which typically exhibit rapid hydrophobic recovery and surface cracking. By extracting excess PDMS oligomers and optimizing plasma activation parameters, they achieve homogeneous functionalization with fluorinated polysiloxane brushes, reducing crack formation. The addition of a smaller molecular silane linker increases polymer brush mobility, enhancing dewetting properties and reducing substrate swelling compared to hydrocarbon functionalities. Linear polymer brushes are confirmed by thermogravimetric analysis, and the optical properties of PDMS remain unaffected by high-frequency plasma activation but are impacted by low-frequency plasma. The functionalized PDMS surfaces show significant reductions in solid adhesion, including for complex contaminants and ice, demonstrating their potential for improved nonstick applications. The study also investigates the stability of the functionalization over time and the mechanical properties of the PDMS substrates, confirming the effectiveness of the approach in creating slippery and anti-adhesion surfaces.This study explores the development of transparent polydimethylsiloxane (PDMS) surfaces with covalently attached lubricants (SOCALs) to enhance anti-adhesion performance. The researchers address the challenges of activating and functionalizing hydrophobic PDMS, which typically exhibit rapid hydrophobic recovery and surface cracking. By extracting excess PDMS oligomers and optimizing plasma activation parameters, they achieve homogeneous functionalization with fluorinated polysiloxane brushes, reducing crack formation. The addition of a smaller molecular silane linker increases polymer brush mobility, enhancing dewetting properties and reducing substrate swelling compared to hydrocarbon functionalities. Linear polymer brushes are confirmed by thermogravimetric analysis, and the optical properties of PDMS remain unaffected by high-frequency plasma activation but are impacted by low-frequency plasma. The functionalized PDMS surfaces show significant reductions in solid adhesion, including for complex contaminants and ice, demonstrating their potential for improved nonstick applications. The study also investigates the stability of the functionalization over time and the mechanical properties of the PDMS substrates, confirming the effectiveness of the approach in creating slippery and anti-adhesion surfaces.