Bio-based glycerol plasticizers for flexible poly(vinyl chloride) blends

A series of glycerol-based compounds were investigated for their application as plasticizers for flexible poly(vinyl chloride) (PVC) blends. The effect of plasticizer chemical structure on the performance, migration behavior, and blend morphology were evaluated and compared to blends produced using the commercial plasticizer dioctyl terephthalate (DOTP). Blends containing 40 phr (parts per hundred rubber) of glycerol-based plasticizer showed a considerable reduction (between 54 to 86 degrees C) in glass transition temperature (T-g) relative to neat PVC (T-g similar to 80 degrees C). Tensile testing of samples prepared with the glycerol analogs demonstrated higher ductility (elongation at break values of up to 97%) than DOTP (elongation at break value of 75%) at identical plasticizer loadings. The surface morphologies showed excellent incorporation of the glycerol plasticizers functionalized with alkyl chains longer than four carbons in length into the PVC matrix, whereas droplet formation was observed in blends with shorter chain glycerol derivatives. Leaching behavior of the plasticized samples were evaluated into different media and showed that plasticizers comprised of branched, or longer alkyl chains produced 2- to 4-fold lower migration rates compared to those with shorter alkyl chains into polar solutions.

Automated summary

A series of glycerol-based compounds were investigated as plasticizers for flexible PVC blends, and were found to have better performance and migration behavior compared to the commercial plasticizer DOTP, showing better incorporation into the PVC matrix.