Passerini and thiol-ene reactions: A facile, green, and efficient route to high-performance bio-based plasticizers

Abstract

The increasing global demand for sustainable alternatives to petroleum-based plasticizers, particularly in poly(vinyl chloride) (PVC) products, has intensified the exploration of bio-based options derived from renewable resources such as plant oils. Traditional bio-based plasticizers, while promising, often suffer from limitations such as low molecular weight, high volatility, and poor compatibility with PVC, thereby restricting their practical applications. To surmount this hurdle, we introduce a novel synthetic route combining the Passerini reaction with the thiol-ene click reaction, aimed at producing high-performance plant oil-based plasticizers (POPs) with enhanced ester content and molecular weight. This method offers significant advantages over traditional methods, including low reaction temperatures (≤40 ​°C), ultrahigh yield (95 ​%) when using ethanol as the solvent, and precise control over ester content. Furthermore, the key findings demonstrate that the designed and synthesized POP (bio-content, 69 ​%) produced using this method exhibits outstanding overall performance, such as excellent migration resistance, good compatibility with PVC, and high thermal stability compared to traditional plasticizers. This facile, green, and efficient method may significantly advance the adoption of bio-based plasticizers, establishing them as a viable alternative to petroleum-based counterparts.