Epoxidized fatty acid tri-ester bio-plasticizer with anti-fogging performance comparable to diisodecyl phthalate

The global scenario on PVC plasticizer is experiencing a drastic change from petroleum-based, toxic di-(2-ethylhexyl) phthalate (DEHP) toward renewable, non-toxic bio-alternatives. However, replacing diisodecyl phthalate (DIDP), a DEHP analogue specifically intended for plasticizing PVC automotive upholstery, with bio-alternative remains a challenge as few bio-plasticizer volatilizes from PVC as slowly as DIDP, a crucial aspect compulsorily required by automotive industry. Here, we demonstrate that covalently attaching two short esters at the α-position of all components of a traditional epoxidized fatty acid methyl ester via a two-step, hydrogen-to-ester nucleophilic substitution in a one-pot procedure yields an epoxidized fatty acid tri-ester bio-plasticizer with remarkably suppressed volatilization from PVC, and hence an extremely low fogging value comparable to DIDP. With this strategy in hand, DIDP, long deemed irreplaceable despite its toxicity and non-renewable nature, may ultimately be phased out.