An approach of non-edible oil based plasticizers for polyvinyl chloride designing: plasticizing mechanisms and properties

Polyvinyl chloride (PVC) is widely used as a commodity plastic in various industries and daily life. However, its green development is limited due to the fact that most plasticizers are either toxic or derived from food products. This study examines the plasticizing mechanisms by comparing three ricinoleic acid esters with different alkyl chain lengths to three commercial plasticizers, including dioctyl terephthalate (DOTP), epoxidized soybean oil (ESO), acetyl tri-n-butyl citrate (ATBC). The results indicate that ester bonds with higher polarity can readily penetrate PVC’s polar barrier and integrate into the polymer chain, while epoxy groups with lower polarity enhance chain stability. Moreover, benzene rings contribute to molecular stability and expand chain spacing. The length of the alkyl chain significantly influences the properties of structurally similar molecules: longer alkyl chains demonstrate greater resistance to migration and improved thermal stability, whereas shorter alkyl chains exhibit better plasticizing effects. Additionally, these ricinoleic acid plasticizers exhibit performance characteristics similar to those of commercial plasticizers in several aspects, underscoring the significant application potential of non-edible ricinoleic acid as a viable candidate to address the sustainability challenges of PVC materials.