Plasma Polymerization of 3‐Aminopropyltrietoxysilane (APTES) by Open‐Air Atmospheric Arc Plasma Jet for In‐Line Treatments

Abstract

In this work, an open‐air arc plasma jet has been studied to polymerize 3‐aminopropyelthrietoxysilane (APTES), which is the most commonly used aminosilane to functionalize surfaces with amine groups. Although the discharge produced from air is highly oxidative and the gas temperature is high as compared to other atmospheric plasma sources, amine groups, as well as amide ones, were identified in the nanometers thick coatings by XPS and FTIR analysis. By comparing the results with post‐treatment and ‐grafting experiments, the partial retention of amine groups might be explained by the non‐ideal mixing of the precursor flow with the main gas stream inside the plasma jet. Beside the intrinsic plasma reactivity, hydrodynamics effects are indeed important when considering flowing atmospheric plasmas.

Investigation of 3‐aminopropyltrimethoxysilane for direct deposition of thin films containing primary amine groups by open‐air plasma jets

“…High‐resolution spectra of the C1s signal (280–300 eV) and N1s (395–415 eV) were performed with an achromatic magnesium anode (Mg Kα = 1253.6 eV) without a neutralizer. The signal was deconvoluted into C = O species (288.0–288.5 eV), C–O/C–N species (286.2–286.7 eV), and C–C/C–H/C–Si species (285.0 eV) for C1s and into C–N–R 2 species (~399.5 eV) and (C = O)–N–R 2 species (~401 eV) for N1s with R = H or C. [ 14 ] Analyses were performed on an area of 0.5 mm 2 at a collecting angle of 45° with respect to the surface normal.…”

Study of a pulsed post‐discharge plasma deposition process of APTES: synthesis of highly organic pp‐APTES thin films with NH2 functionalized polysilsesquioxane evidences

“…[5,[17][18][19] Among the various processes that enable deposition of NH 2 -rich thin films, PACVD, also called plasma polymerization, can lead to conformal and adherent amino containing layers. [9][10][11][12]15,[20][21][22][23][24][25][26][27][28][29][30][31][32][33] With this process, an organic precursor (monomer) containing an −NH 2 group is activated by a plasma, that is, turned into a radical. The radicals then react and condense on a substrate thus leading to the thin film growth.…”

“…Among them, (3-Aminopropyl)triethoxysilane (APTES) is an aminoalkoxysilane that is known to achieve dense and adherent coatings. [8,11,13,14,16,28,31,32,[35][36][37][38] It is widely used in sol-gel methods as it allows the deposition of amino-rich layers. [8,13,16,36,37] Compared to other −NH 2 containing precursors, this aminosilane can provide a siloxane backbone that can provide dense silica-like layers that are known to be highly adherent on metallic surfaces, resistant to delamination and act as a barrier against diffusion.…”

“…Indeed, −NH 2 rich thin films are already known to immobilize bioactive molecules, improve implants biocompatibility and enhance chemical adhesion . Among the various processes that enable deposition of NH 2 ‐rich thin films, PACVD, also called plasma polymerization, can lead to conformal and adherent amino containing layers . With this process, an organic precursor (monomer) containing an −NH 2 group is activated by a plasma, that is, turned into a radical.…”

“…Different monomers have been already reported to synthesize amino containing thin layers. Among them, (3‐Aminopropyl)triethoxysilane (APTES) is an amino‐alkoxysilane that is known to achieve dense and adherent coatings . It is widely used in sol‐gel methods as it allows the deposition of amino‐rich layers .…”