Urethane Bond-Mediated Cross-Linking of Natural Rubber with Functionalized Silica Nanoparticles: Achieving Multifold Enhancement of Material Properties

In this study, we explore an approach for the synthesis of natural rubber (NR) conjugates or composites, aiming to enhance reproducibility, reliability, and diversity in practical applications. Traditional methods often involve cross-linking NR followed by the addition of nanomaterials through noncovalent interactions. However, our approach integrates suitably functionalized silica nanomaterials via covalent bonds during the cross-linking process. To evaluate the efficacy of this method, we compared the resulting materials with those synthesized using different diisocyanates and nonfunctionalized silica nanoparticles. We conducted a detailed analysis of the mechanical properties of the produced composites, correlating them with crosslink density, to assess the impact of our strategy. Preliminary studies also indicated that the materials exhibit partial biodegradability, suggesting their potential for sustainable application. Our findings offer new insights into the design of NR conjugates or nanocomposites with enhanced properties and environmental benefits.