Epoxidized soybean oil (ESBO) is a bio-based plasticizer derived from soybean oil. It is produced through a chemical process called epoxidation, where soybean oil is reacted with hydrogen peroxide and an organic acid catalyst. This reaction introduces epoxy groups into the molecular structure of the oil, resulting in the formation of ESBO.

ESBO is commonly used as a plasticizer, a substance added to polymers to enhance their flexibility, durability, and processability. It serves as an alternative to traditional phthalate-based plasticizers, which have raised concerns due to their potential health and environmental impacts. ESBO offers several advantages, including its non-toxic nature, high compatibility with various polymers, and good thermal and UV stability. It improves the properties of materials such as polyvinyl chloride (PVC) by imparting flexibility, heat resistance, and enhanced mechanical strength. Additionally, ESBO has found applications in food packaging, adhesives, sealants, coatings, and paints.