Electrodeposition of organofunctional silanes and its influence on structural adhesive bonding

Abstract

Four different organofunctional silanes were selected and deposited on chemically pretreated aluminum surfaces by immersion and electrodeposition techniques. The surface morphology, comparison of elemental constituents, and surface free energies of silane-coated aluminum were investigated by low voltage scanning electron microscopy (LVSEM), low voltage X-ray analysis (LVXA), and contact angle measurement, respectively. The initial bond strength and long-term durability were evaluated with epoxy adhesive by lap shear tests. The deposition of silane coupling agents enhanced the bond durability of aluminum/epoxy joints under heat and humidity conditions. Also the performance of silane coupling agents depended on the application method. The electrodeposition technique produced a more uniform coverage of silane on the aluminum surface and, thus, was generally more effective than the immersion technique in improving bond performance.

Organosilanes and polypyrrole as anticorrosive treatment of aluminium 2024

“…For hydrolysed silane to condense on the AA2024 surface forming Al-O-Si bonds, the metal surface must be coated with OH groups, for which the presence of an oxide layer (Al 2 O 3 ) is necessary [23][24][25]. For this purpose, an Al 2 O 3 layer of a controlled thickness was formed on the untreated aluminium surface (i.e.…”

Optimizing Silanization to Functionalize Stainless Steel Wire: Towards Breast Cancer Stem Cell Isolation

“…During electrodeposition of silane, applied negative potential causes the formation of hydroxyl ions that catalyze the binding of silane on the surface [ 31 ]. The electrodeposition of silane-coupling agents offers a more uniform coating [ 32 ] and the possibility of controlling thickness and geometrically coating complex shapes [ 33 ]. By using electrodeposition, it is possible to avoid additional steps in surface modification (surface hydroxyl generation).…”

A Review of Recent Developments in Coating Systems for Hot-Dip Galvanized Steel

“…For the aim of further improving the corrosive inhibition properties of above-mentioned silane films, electrochemical deposition technology is introduced into preparing these organic silane films (Woo et al, 1993;Shacham et al, 1999;Sheffer et al, 2003;Gandhi and van Ooij, 2004). Hu's group has done numerous research on this aspect (Hu et al, 2006(Hu et al, , 2007Li et al, 2010;Jiang et al, 2015;Liu et al, 2017;Xu et al, 2018).…”