The Influence of Substrate Preparation on the Performance of Two Alkyd Coatings After 7 Years of Exposure in Outdoor Conditions
Abstract
1. Introduction
2. Materials and Methods
2.1. Materials
2.2. Treatment Method
- •
- Series 1—containing control samples, directly coated with the two alkyd products (coded C-Alk1 and C-Alk2).
- •
- Series 2—containing samples pre-treated by short time immersion (15 min at 20 °C) with the three types of resins (R1, R2, R3) and then coated with the brown impregnation lasure (Alk1).
- •
- Series 3—involved resin pre-treated samples, subsequently coated with the white, glossy alkyd enamel (Alk2).
2.3. Exposure
2.4. Assessment of Wood and Coating Degradation
2.4.1. Macroscopic Evaluation
2.4.2. Microscopic Investigation
2.4.3. ImageJ Analysis of the Coating Film
2.4.4. Statistical Analysis
3. Results and Discussion
3.1. Aspects of Degradation of Coated Wood Surfaces
3.2. Influence of Resin Pre-Treatments on Wood Cracking and Adherence of Coating Films: Visual, Non-Destructive Assessment After 7 Years of Exposure
3.3. ImageJ Analysis of Coating Film Loss After 7 Years of Exposure
3.4. Cross-Cut Test
3.5. Statistics
3.6. In-Time Evolution of Wood Cracking and Adherence During Outdoor Exposure
3.7. Influence of Exposure Situation on the Adherence of the Coating Films After 7 Years of Exposure
3.8. Influence of Resin Pre-Treatments on Biological Degradation of Coated Surfaces
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Characteristics | Code of Treatments | ||||||
---|---|---|---|---|---|---|---|
R1 | R2 | R3 | Alk1 | Alk2 | |||
Type | Acryl-polyurethane waterborne resin | Epoxy resin | Alkyd-polyurethane Resin in solvent | Biocide semi-transparent alkyd lacquer | White glossy alkyd enamel | ||
Solid content, % | 24.1 | 43.05 | 28.22 | 36 | 39.18 | ||
Viscosity, Tsc Φ4 mm, 20 °C, s | 12 | 12 | 12 | 13 | 45 | ||
Resin/product uptake, g/m2 | 323 | 311 | 247 | Control | Pre-treated | Control | Pre-treated |
85 | 82 1*, 50 2*, 73 3* | 182 | 202 1* 120 2* 255 3* |
One-Way ANOVA Response | Source | DF | Adj SS | Adj MS | F-Value | p-Value |
---|---|---|---|---|---|---|
Cross Cut | Pre-treatment | 4 | 2.490 | 0.6224 | 0.26 | 0.902 |
Coating | 1 | 44.010 | 44.0104 | 208.41 | 0.000 |
Solution | Pre-Treatment | Coating | Cross-Cut Fit | Composite Desirability |
---|---|---|---|---|
1 | R3 | Alk 2 | 1.97368 | 0.756579 |
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Beldean, E.C.; Timar, M.C.; Manea, E.-A.S. The Influence of Substrate Preparation on the Performance of Two Alkyd Coatings After 7 Years of Exposure in Outdoor Conditions. Coatings 2025, 15, 918. https://doi.org/10.3390/coatings15080918
Beldean EC, Timar MC, Manea E-AS. The Influence of Substrate Preparation on the Performance of Two Alkyd Coatings After 7 Years of Exposure in Outdoor Conditions. Coatings. 2025; 15(8):918. https://doi.org/10.3390/coatings15080918
Chicago/Turabian StyleBeldean, Emanuela Carmen, Maria Cristina Timar, and Emilia-Adela Salca Manea. 2025. "The Influence of Substrate Preparation on the Performance of Two Alkyd Coatings After 7 Years of Exposure in Outdoor Conditions" Coatings 15, no. 8: 918. https://doi.org/10.3390/coatings15080918
APA StyleBeldean, E. C., Timar, M. C., & Manea, E.-A. S. (2025). The Influence of Substrate Preparation on the Performance of Two Alkyd Coatings After 7 Years of Exposure in Outdoor Conditions. Coatings, 15(8), 918. https://doi.org/10.3390/coatings15080918