The impact of double bonds in the APPECVD of acrylate-like precursors

Abstract

In this study, we investigated the atmospheric plasma polymerization of allyl methacrylate (AMA), n-propyl methacrylate (nPMA), and propyl isobutyrate (PiB), whose chemistry mainly differs by their number of unsaturations. The resulting material is characterized using X-ray photoelectron spectroscopy (XPS) and infrared reflection absorption spectroscopy (IRRAS) while the thickness of the coatings is determined by visible spectroscopic ellipsometry (Vis-SE). The results show that the concentration of ester groups at the surface of the plasma polymers, as well as their deposition rate strongly depends on the surrounding unsaturations present in the precursor. A stabilization of the ester groups and an increase in the deposition rate due to the carbon-carbon double bonds is suggested. This study focuses on the atmospheric pressure plasma deposition of molecules that only differ by their number of unsaturations, namely allymethacrylate, n-propylmethacrylate, and propyl isobutyrate. The chemical composition and thickness of the resulting coatings, as well as the influence of plasma power are compared. A stabilization of the ester groups and an increase in the deposition rate due to the carbon-carbon double bonds is suggested. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.