And yet, it became quickly obvious that in view of the complexity of the growth mechanism, fine control of the layers properties can only be reached by understanding at a fundamental level the mechanistic formation of the layers. For such materials, controlling the chemistry of the coatings by a clever choice of the process parameters represents the main challenge. Since the 1980s, functionalized plasma polymer films have attracted a considerable attention owing to their promising utilization in a wide range of modern applications. The interest in this class of materials arises from their potential use in modern fields of applications including the development of supports for biomolecules immobilization or cell growth, interlayers for promoting adhesion of metal coatings, biocompatible or antibacterial coatings, controlled drug release coatings, superhydrophobic surface, conductive layers ,etc. In this context, functionalized PPF containing/supporting \ \COOH, \ \OH, \ \NH 2, \ \COOR, \ \COR, \ \CFx, \ \Br, \ \SH, thiophene-based units have been developed. Since the 1980s, with the rise of micro-and nano-technologies, plasma polymerization has been further developed in the search for PPF with controlled and tailored chemistry while keeping their other inherent properties. The chemical, physical stability of the films is then related to the mechanisms of deposition, the energy density provided to the surface during film growth. The results show that films generated from EDA plasmas are generally unstable in aqueous media, while films generated from AA plasmas exhibit higher stability, particularly those deposited at high RF power. Film stability was assessed by comparing X-ray photoelectron spectroscopy XPS, atomic force microscopy AFM measurements before, after washing in phosphate buffered saline PBS. Deposition rate, ion flux, ion energy, plasma phase mass spectrometry were used to investigate the plasma-surface interactions. Plasma polymer films from AA, EDA were produced at radio frequency RF powers between 2 and 20 W at a constant monomer flowrate. Here we investigate the relationship between plasma parameters, film stability for two commonly used monomers, allylamine AA, ethylenediamine EDA. One issue with generating such plasma polymers is the need to generate sufficient amine density on the surface to enable binding, while simultaneously maintaining the chemical, physical stability of the surface in aqueous media. Amine containing plasma polymer films are of interest due to their ability to bind biomolecules either covalently or electrostatically.
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