Multi-branched octopus-like plasticizers with excellent plasticizing performance in poly(vinyl chloride)

The development of alternatives is a priority issue for the plasticizer industry due to the reproductive toxicity and potential carcinogenicity of phthalate plasticizers. Herein we demonstrate the synthesis and characterization of multi-branched octopus-like plasticizers applied in poly(vinyl chloride) (PVC). The plasticizers were achieved through a straightforward one-step esterification reaction, resulting in four polyol ester plasticizers (glyceryl tri-n-octanoate [GTOE], pentaerythritol tetra-n-octanoate [PQOE], xylitol penta-n-octanoate [XPOE], and mannitol hexa-n-octanoate [MHOE]). The multi-branched structure enhances the interactions between plasticizers and PVC molecules leading to superior plasticizing properties, particularly mechanical properties, thermal stability, and migration resistance compared with commercial plasticizers di(2-ethylhexyl) phthalate (DEHP), dioctyl terephthalate (DOTP), and acetyl tributyl citrate (ATBC). Concretely, the elongation at break of MHOE/PVC (825%) and PQOE/PVC (814.63%) was better than that of DEHP/PVC (670.02%), DOTP/PVC (490.62%) and ATBC/PVC (566.78%). The T5% of GTOE/PVC, PQOE/PVC, XPOE/PVC, and MHOE/PVC were 46.97, 67.24, 60.09 and 48.14 degrees C higher than ATBC/PVC respectively. In the volatility resistance testing after 48 h, the weight loss of GTOE/PVC, PQOE/PVC, XPOE/PVC, and MHOE/PVC was 5.63%, 3.64%, 2.95%, and 8.88% respectively, which was far less than DEHP/PVC (15.58%), DOTP/PVC (11.83%) and ATBC/PVC (18.15%). Consequently, the obtained plasticizers demonstrate enhanced plasticizing efficiency, presenting promising alternatives to phthalate plasticizers and expanding the repertoire of choices within the plasticizer industry. The octopus-like plasticizers with multi-branched structures were used as primary plasticizers in poly(vinyl chloride) and exhibited superior mechanical properties, thermal stability and migration resistance than commercial plasticizers. image