| AVS 63rd International Symposium & Exhibition | |
| Plasma Science and Technology | Thursday Sessions |
| Session PS-ThP |
| Session: | Plasma Science and Technology Division Poster Session |
| Presenter: | Delphine Merche, Université Libre de Bruxelles, Belgium |
| Authors: | B. Nisol, Université Libre de Bruxelles, Belgium J. Guesquière, Université Libre de Bruxelles, Belgium D. Merche, Université Libre de Bruxelles, Belgium N. Vandencasteele, Université Libre de Bruxelles, Belgium F. Reniers, Université Libre de Bruxelles, Belgium |
| Correspondent: | Click to Email |
Plasma polymerization is an eco-friendly route (low temperature, solvent-free process) used to prepare functional thin films with desired properties (e.g aesthetics coatings, protective coatings against corrosion and abrasion, coatings for adhesion and barrier properties…) on any kinds of substrates. In this study, transparent acrylate coatings were synthesized by PECVD under atmospheric pressure, from the simultaneous injection of acrylic acid (AA) and propargyl methacrylate (propaMA) into a dynamic DBD, using argon as the carrier gas.
The influence of the ratio AA/propaMA and the power on the physical and chemical properties of the coatings deposited onto various substrates (Si wafers, polyolefins films and thick gold films) was highlighted by WCA (wettability), mechanical profilometry (thickness), XPS and FTIR-IRRAS (chemical composition).
The addition of propaMA to AA allows reaching high deposition rates (up to 11 nm/sec) thanks to its highly unsaturated (and reactive) nature.
WCA results evidenced the possibility to tune the surface wettability from highly hydrophobic (140° for the pure propaMA coatings) to highly hydrophilic (15° for the pure AA coatings). Moreover, the coatings were very stable over time and were seen not to suffer from hydrophobic recovery. Indeed, the WCA remained constant for at least a period of 2 months.
The highly hydrophobic character of pure propaMA coatings is due to an important texturization of its surface, as revealed by scanning electron micrographs (SEM); the high reactivity of propaMA is thought to induce gas-phase polymerization, and to the subsequent formation of globular features. Also, in the explored conditions, smooth coatings could only be obtained for high AA proportions in the gas mixture.
XPS and FTIR results revealed the presence of alcohol and ketones groups in addition to the carboxylic/esters functions of the monomer precursors. The COOR groups related to the presence of carboxylic acid increase with the proportion of AA in the AA/propaMa mixture while the C-O and C=O groups decrease.
Thanks to excellent ageing properties, such thin and transparent coatings represent a promising alternative to polymer surface plasma functionalization.
We would like to thank the Belgian Federal Government IAP- (interuniversity program) “Physical Chemistry of Plasma Surface Interactions” P7/34, and the Walloon Region.