TY - JOUR
T1 - Stability of Octadecyltrimethoxysilane-Based Coatings on Aluminum Alloy Surface
AU - Zhizhchenko, Alexey Y
AU - Shabalina, Anastasiia V
AU - Al Julaih, Ali
AU - Gurbatov, Stanislav O
AU - Kuchmizhak, Aleksandr A
AU - Iwamori, Satoru
AU - Kulinich, Sergei A.
N1 - KAUST Repository Item: Exported on 2022-04-26
Acknowledgements: Support from the Russian Science Foundation (project no. 21-79-10304)
PY - 2022/2/28
Y1 - 2022/2/28
N2 - Long-term stability in contact with water of organosilane layers formed by octadecyltrimethoxysilane (ODTMS) on polished aluminum alloy (AA2024) through dip-coating was studied by combining SEM, water contact angle measurements, and X-ray photoelectron spectroscopy. Similar organosilane layers were formed on AA2024 coated with permanganate conversion coating, 1,2-bis(triethoxysilyl)ethane (BTSE) and hydrated SiOx as under-layers, after which their long-term durability was also tested. During immersion in water for about one month, all the samples exhibited a decrease in hydrophobicity, implying the prepared organosilane layer was not stable over time, gradually hydrolyzing and letting water interact with the underlying layer. In parallel, SEM images of one-layer samples taken after immersion showed clear signs of local electrochemical corrosion, while XPS analysis confirmed a loss of silicon from the surface layer. The highest stability over time was demonstrated by a one-layer sample prepared in an ethanol/water bath for 5 min and by a similar ODTMS layer prepared on hydrated MnOx as an under-layer.
AB - Long-term stability in contact with water of organosilane layers formed by octadecyltrimethoxysilane (ODTMS) on polished aluminum alloy (AA2024) through dip-coating was studied by combining SEM, water contact angle measurements, and X-ray photoelectron spectroscopy. Similar organosilane layers were formed on AA2024 coated with permanganate conversion coating, 1,2-bis(triethoxysilyl)ethane (BTSE) and hydrated SiOx as under-layers, after which their long-term durability was also tested. During immersion in water for about one month, all the samples exhibited a decrease in hydrophobicity, implying the prepared organosilane layer was not stable over time, gradually hydrolyzing and letting water interact with the underlying layer. In parallel, SEM images of one-layer samples taken after immersion showed clear signs of local electrochemical corrosion, while XPS analysis confirmed a loss of silicon from the surface layer. The highest stability over time was demonstrated by a one-layer sample prepared in an ethanol/water bath for 5 min and by a similar ODTMS layer prepared on hydrated MnOx as an under-layer.
UR - http://hdl.handle.net/10754/676459
UR - https://www.mdpi.com/1996-1944/15/5/1804
UR - http://www.scopus.com/inward/record.url?scp=85125811020&partnerID=8YFLogxK
U2 - 10.3390/ma15051804
DO - 10.3390/ma15051804
M3 - Article
C2 - 35269035
SN - 1996-1944
VL - 15
SP - 1804
JO - Materials (Basel, Switzerland)
JF - Materials (Basel, Switzerland)
IS - 5
ER -