Monohexyl phthalate is primarily used as an intermediate in the production of various chemical compounds, particularly in the synthesis of plasticizers. These plasticizers are essential in enhancing the flexibility, durability, and workability of polymers, especially polyvinyl chloride (PVC). It is also utilized in research and development to study the behavior and effects of phthalate esters in different environments. Additionally, it serves as a reference standard in analytical chemistry for detecting and quantifying phthalate derivatives in environmental and biological samples, aiding in the assessment of exposure and potential health risks.