| Abstract: | The oil displaceing and absorbing behaviors of epoxy adhesives cured with amidoamine curing agents on oiled metal substrates were studied using X-ray photoelectron spectroscopy (XPS) and attenuated total reflection infrared spectroscopy (ATR). A Simple XPS experiment demonstrated that amidoamine curing agents could displace an aliphatic oil from the cold-rolled steel (CRS) and the electrogalvanized steel (EGS) surfaces, but an epoxy resin based on bisphenol A could not. Results of ATR measurements sowed that the oil was effectively displaced from the CRS surface and absorbed as deep as 2 μm into the epoxy adhesive cured with amidoamine with low amine numbers. But the oil was mostly present in the 0.3 μm thick adhesive layer near the CRS/adhesive interface for the epoxy adhesive cured with amidoamine with high amine numbers. The oil absorbing ability of the adhesive was worse on the oiled EGS substrate than on the oiled CRS substrate. It was also found that the pressure applied during cure could greatly facilitate the absorption of oil into the adhesive. © 1995 John Wiley & Sons, Inc. |
