A Comprehensive Review of Polyurethane Composites: From Macro to Nano and Beyond

Polyurethanes have attracted significant and constant attention since their initial introduction by Otto Bayer in 1937, primarily due to their inherent versatility. To expand their application potential and overcome limitations under extreme industrial conditions, the performance of pure polyurethanes is frequently enhanced through the incorporation of adequate fillers. This review provides a comprehensive analysis of recent advancements in the field of polyurethane composites, focusing on the role of functional fillers in improving the properties of the polyurethane matrix. Special attention is given to the classification and effects of various types and sizes of the most commonly applied and promising fillers, including both individual and hybridized systems.