Adhesion and Long-Term Barrier Restoration of Intrinsic Self-Healing Hybrid Sol–Gel Coatings

Adhesion and Long-Term Barrier Restoration of Intrinsic Self-Healing Hybrid Sol–Gel Coatings

Type	Journal Article
Author	Mina Abdolah Zadeh
Author	Sybrand van der Zwaag
URL	http://dx.doi.org/10.1021/acsami.5b11867
Volume	8
Issue	6
Pages	4126-4136
Publication	ACS Applied Materials & Interfaces
Date	February 17, 2016
Abstract	Self-healing polymeric coatings aiming at smart and on-demand protection of metallic substrates have lately attracted considerable attention. In the present paper, the potential application of a dual network hybrid sol–gel polymer containing reversible tetrasulfide groups as a protective coating for the AA2024-T3 substrate is presented. Depending on the constituent ratio, the developed polymer exhibited a hydrophobic surface, high adhesion strength, and an effective long-term corrosion protection in 0.5 M NaCl solution. Upon thermal treatment, the healable hybrid sol–gel coating demonstrated full restoration of the barrier properties as well as recovery of the coating adhesion and surface properties (e.g., hydrophobicity and surface topology) necessary for lifetime extension of corrosion protective coatings. Excellent long-term barrier restoration of the coating was only obtained if the scratch width was less than the coating thickness.