Application of waste poly(ethylene terephthalate) in the synthesis of new oligomeric plasticizers

New method of transesterification of waste poly(ethylene terephthalate) (PET) with aliphatic oligoesters was developed. The structures of obtained oligoesters were identified by NMR, ESI-MS and SEC methods, and then correlated with physical properties determined by DSC and TGA analyses. Physico-chemical properties of synthesized plasticizers were compared with monomeric and polymeric commercial products. Products of the reaction of PET with oligoesters based on azelaic acid with 1.4-butanediol and adipic acid with triethylene glycol occurred to be remarkable substitutes of commercial plasticizers. They possessed lower volatility and much higher thermal stability. Insertion of glycerol unit into aliphatic oligoester and using it for the process of PET depolymerization resulted in obtaining of plasticizers of branching structure with glycerol unit as a core. They possessed lower viscosity and higher molecular mass in comparison with their linear equivalents.