Recent Advances in the Research and Application of Protective Composites for Stone Surfaces

The degradation of stone surfaces resulting from natural aging and environmental factors poses significant challenges to material durability and esthetics. This review systematically summarizes recent advances in composite protective materials designed to enhance stone surface preservation. It focuses on the classifications and fundamental properties of organic polymer-based materials, inorganic nanocomposites, and multifunctional protective coatings, emphasizing their physicochemical, mechanical, and environmental performance. The review further analyzes case studies across various stone substrates, such as marble, limestone, sandstone, and granite, highlighting substrate-specific coating compatibility and protective effectiveness against water ingress, biological colonization, graffiti, and pollutant deposition. Critical factors influencing protective performance, including stone mineralogy, coating composition, environmental conditions, and application protocols, are elucidated. Finally, existing challenges and future research directions are identified, underscoring the need for environmentally friendly, multifunctional, and durable composite coatings with enhanced substrate adaptability and simplified application processes.