Inhibition of acid undercutting of inorganic/organic hybrid polyurethane coatings
| Autor: | Homero Castaneda, Mark D. Soucek, Ximing Li, Zhouying He |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Zirconium
Materials science General Chemical Engineering Organic Chemistry chemistry.chemical_element 02 engineering and technology engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences 0104 chemical sciences Surfaces Coatings and Films Dielectric spectroscopy Corrosion Tetraethyl orthosilicate chemistry.chemical_compound chemistry Coating Chemical engineering Materials Chemistry engineering 0210 nano-technology Porosity Titanium Polyurethane |
| Zdroj: | Progress in Organic Coatings. 134:169-176 |
| ISSN: | 0300-9440 |
| Popis: | This study investigated the corrosion resistance of inorganic/organic hybrid polyurethane based coatings by using a mixture of sol-gel precursors. Four sol-gel precursor, tetraethyl orthosilicate (TEOS), titanium(IV) isopropoxide (TIP), and zirconium(IV) propoxide (ZRP), were utilized in this study. Salt spray, acid undercutting, and electrochemical impedance spectroscopy (EIS) were conducted to study the anticorrosion behavior of the coatings. Generally, samples based on mixed sol-gel precursors exhibited better protection compared to the urethane coating without sol-gel precursors or the coating with only TEOS as the single sol-gel precursor. In acid undercutting experiments, mixed sol-gel precursor samples provided the best results compared to the control and TEOS-based samples. Comparison of parameters extracted by EIS describing water uptake indicates mixed sol-gel precursor composition had the best anticorrosion performance, which was consistent with acid undercutting results. The impedance of the hybrid coatings, at the order of 1010 ohms cm2 at 0.01 Hz, were ca. 3 orders higher than the control sample. Coating capacitance for all the hybrid coatings were stable throughout the immersion time while that for the control sample had a significant change after short time. The water uptake for the control sample was close to 2.5% while that for all the hybrid coatings were about or lower than 0.5%. Morphology from SEM revealed that the organic inorganic sample with TEOS/TIP/ZRP mixed precursors maintained the coating integrity while higher porosity was developed in the control sample. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect