Abstract
The objective of this study was to synthesize thermoplastic elastomers by the direct copolyesterification of reactive oligomers of poly[(ethylene terephthalate)-co-(ecaprolactone)] (PET) and poly(propylene oxide) (PPO). The synthesis of hard segment oligomers was achieved in two steps. The first step consisted of the glycolysis of PET leading to a,o-hydroxyl functionalized oligomers. The second step corresponded to the ring opening polymerization of e-caprolactone onto the hydroxyl end groups of thePEToligomers. Commercially available hydroxytelechelic poly(propylene oxide) was modified to obtain carboxytelechelic poly(propylene oxide). The chemical structure of the product was investigated by 1H NMR and size exclusion chromatography (SEC). Multiblock poly(ester-ether) was then synthesizedbypolyesterificationofhydroxytelechelicpoly[( ethylene terephthalate)-co-(e-caprolactone)] with carboxytelechelic poly(propylene oxide) oligomers, using different catalysts and reaction conditions. The best stoichiometric ratio for the reaction was determined in order to obtain the highest possible Mn. The chemical structure of the synthesized poly(ester-ether) was investigated by size exclusion chromatography and 1H NMR. The thermal and thermomechanical behavior of the synthesized poly(ester-ether) was investigated by differential scanning calorimetry and dynamic mechanical analysis, which showed that the poly(ester-ether) behaved as a thermoplastic elastomer. This product could also be an interesting way for chemical recycling of PET waste.