ABSTRACT
Variation of surface chemical energy and its effects on adhesion strength and corrosion protection properties of epoxy coatings of mild steel substrates were studied. Results indicated that pre-treatment with a mixture of 3-glycidoxypropyltrimethoxysilane, sodium dodecylbenzene sulphonates and zinc sulphate inhibitors enhanced the corrosion protection properties of epoxy coating when compared to untreated substrates. The formation of a compact insoluble layer of zinc hydroxide/oxide together with SDBS complex on the mild steel surface was found to affect the adhesion properties and resistance towards cathodic/anodic delamination of epoxy coating. This was primarily caused by the formation of strong interfacial interaction and increased in surface passivation. The findings suggested, adhesion alone plays a little part in preventing underfilm corrosion. The underfilm corrosion activities are determined by surface passivity towards corrosion reactions.
Acknowledgements
The authors would like to thank the Faculty of Applied Sciences, Universiti Teknologi MARA for permitting to publish this paper and the Malaysian Rubber Board for their technical support of the tasks.
Disclosure statement
No potential conflict of interest was reported by the author(s).