Uniform and large-scale plasma polymerized hexamethyldisiloxane surfaces with high water contact angles

In the past decade, the fabrication of hydrophobic polymer surfaces has been an interesting subject attracting a great deal of research, because such surfaces possess a set of unique functional properties such as water-proof, corrosion-resistant and anti-fouling which can be used in various fields. Among various treatment methods, atmospheric pressure plasma polymerization (APPP) is regarded as a low-cost and environment-friendly alternative to chemical methods and low-pressure plasmas. However, uniform surface modification on a large scale can be hardly realized by APPP technology. In this study, the surface modification of polyethylene terephthalate (PET) films using APPP with hexamethyldisiloxane (HMDSO) as a precursor was studied. The plasma was generated in an atmospheric pressure argon RF discharge system. The wetting behavior of the modified PET surface and the treatment uniformity were evaluated via water contact angle (WCA) measurements. As shown in Fig.1, the WCA of the surface increased from untreated 75.6±0.6° to treated 144.7±2.3°, which is quite higher compared to the traditional HMDSO plasma deposition on PET film. Additionally, chemical composition and surface roughness of the modified surface were investigated by X-ray photoelectron spectroscopy, Fourier-transform infrared spectroscopy, atomic force microscopy, and scanning electron microscope. In conclusion, a uniformly modified, large scale (18×10 cm2) PET film with high WCA was achieved by using APPP technology, which is very promising for hydrophobic surface applications.

Publication year:2019