High-performance and sustainable clear water-based coatings for outdoor wood protection: A review

Abstract

Clear water-based coatings have emerged as a promising solution to preserve the natural appearance of wood while enhancing its durability. However, achieving long-term stability in outdoor environments remains a major challenge for commercially available clear coatings. This study explores the potential of nanomaterials in improving the performance of these coatings. Inorganic nanoparticles can enhance UV resistance, transparency, mechanical strength, water repellency, and thermal stability. On the other hand, organic nanomaterials such as nanocellulose offer reinforcement capabilities, thermal stability, and biodegradability. However, challenges such as proper dispersion of nanomaterials in coatings, long-term durability, cost, and environmental and health impacts must be addressed. To overcome these obstacles, synergistic strategies combining various nanomaterials with complementary properties, hybrid nanocomposite systems, surface-modified nanomaterials, and multifunctional nanomaterials have been investigated. Additionally, emerging nanomaterials such as two-dimensional (2D) nanomaterials, self-healing materials, and biomimetic materials present new opportunities for the development of high-performance and sustainable clear wood coatings. This study highlights the importance of interdisciplinary collaborations, comprehensive assessments of environmental and health impacts, and the establishment of appropriate standards and guidelines. The advancement of these coatings can promote the widespread adoption of wood as a low-maintenance, visually appealing, and environmentally sustainable material for outdoor applications.