Used primarily as an intermediate in the production of plasticizers, isononanol helps improve the flexibility and durability of polymers, especially in polyvinyl chloride (PVC). Its branched-chain structure contributes to better low-temperature performance and enhanced hydrolytic stability in plasticized materials. It is also employed in the synthesis of lubricants, surfactants, and emollients for cosmetics due to its good solubility and mild skin compatibility. Additionally, isononanol finds use in coatings and adhesives formulations where low volatility and improved weathering resistance are required.