Study of the Silicon/?-APS/Pyralin Assembly Interfaces by X-ray Photoelectron Spectroscopy

Abstract

Polyimides have been extensively studied in view of their wide industrial applications. Adhesion to a substrate is essential for normal operation of devices. This problem is often solved by the use of an adhesion promoter on the surface of interest. A surface‐sensitive technique such as XPS has proved to be a powerful analytical tool for the analysis of the polymer/substrate interface. In the present paper, the interfaces of the SiO2/γ‐aminopropyltriethoxysilane (γ‐APS)/Pyralin system have been investigated at a precured stage. A detailed analysis of the molecular structures formed at the interface is carried out using XPS spectroscopy. An attribution of the various peak components is made with the help of accurate calculations of presumed core‐electron binding energies using a recent procedure based on the Density Functional Theory. Two acid–base mechanisms are described. The first one occurs between the ammonium end of the γ‐APS molecule and the silicon surface hydroxyl (NH3U+SiO‐), whereas the second one is formed between the ammonium end of the γ‐APS and the polymer carboxylic function (NH3U+COO‐). The results at the first interface are in contradiction with the expected stable oxygen‐bridged bond (siloxane), thus the rearrangement of the γ‐APS molecule upon heating, as suggested by Linde in a dynamic ‘Flip model,’ has been studied.

Operation of vehicles in AGV system and method for analyzing operation

“…The Si 2p peak is detected at 103.2 eV which attributed to SiOCH 3 . While, the occurrence of C 1s peak at 285 eV is due to CCH 2 C. This result agrees with the literature which reported using E‐glass slide surface coated by APTES [35, 36]. At 399 eV, the N 1s is observed which corresponds to the free amine group from APTES, whereas the minor component at 400.6 eV was due to its protonated form or to an SiOH…H 2 N hydrogen bond [37].…”

Surface‐activated nanosilica treated with silane coupling agents/polypropylene composites: Mechanical, morphological, and thermal studies

“…The Si 2p peak is detected at 103.2 eV which attributed to SiÀ ÀOÀ ÀCH 3 . While, the occurrence of C 1s peak at 285 eV is due to CCH 2 C. This result agrees with the literature which reported using E-glass slide surface coated by APTES [35,36]. At 399 eV, the N 1s is observed which corresponds to the free amine group from APTES, whereas the minor component at 400.6 eV was due to its protonated form or to an À ÀSiOH.…”

Characterization and Transport Properties of Nafion/Polyaniline Composite Membranes

“…We believe that this peak can be attributed to bicarbonate (HCO 3 -) adsorbed on PANI. In fact, George et al 50 have characterized the -NH 3 + HCO 3 -compound using XPS by the following peaks: 531.9 eV for the O1s in HCO 3 -and 288.8 eV for the C1s in HCO 3 -. When fitting the C1s spectra of Nafion-PANI membranes, a peak is found at approximately 289.3 eV.…”