Innovating PVC plasticization: performance and potential of a lauric acid ester-amide plasticizer

The need to replace phthalate plasticizers in PVC has arisen due to health concerns, with some, like DOP, suspected of being carcinogenic, though not definitively proven. This study explores the use of lauric acid to synthesize a novel plasticizer, BDL, through a two-step reaction involving Benzoyl chloride, Diethanolamine, and Lauric acid. The structure of BDL was confirmed through FTIR and ¹H NMR analyses. BDL effectively replaced DOP in PVC samples at concentrations ranging from 10 to 40 phr. The mechanical, X-ray diffraction, thermal, exudation, and colorimetric properties of the resulting PVC sheets were evaluated, demonstrating BDL’s good plasticizing performance and integration into PVC matrices. Notably, PVC containing 40 phr BDL (PVC BDL40) showed a 47.18% reduction in tensile strength, a 64% decrease in tensile modulus, and a ~ 49-fold increase in elongation-at-break. The glass transition temperature (T_g) decreased as BDL content increased, further enhancing flexibility. Despite BDL’s dark color potentially limiting its application, it successfully replaced DOP in certain PVC formulations, offering an environmentally friendly alternative. The BDL synthesis involved forming the benzoyl ester of diethanolamine, followed by reacting this ester with lauric acid without solvents or catalysts. While BDL exhibited higher viscosity due to intermolecular forces, its performance as a PVC plasticizer was remarkable, particularly in mechanical flexibility and stability in exudation tests. This research highlights BDL’s potential as a green plasticizer with significant impacts on PVC properties, despite the challenge of coloration.

Graphical abstract