Synthesis, characterization, mechanical and thermal properties of random poly (butylene adipate-co-ethylene terephthalate)

A series of novel aliphatic-aromatic copolyesters based on poly(butylene adipate) (PBA) and poly(ethylene terephthalate) (PET) has been synthesized and characterized. The composition and microstructure of the prepared copolyesters were characterized by 1HNMR and 13CNMR, respectively. It was observed that the PBA sequence length decreases with ethylene terephthalate content. All copolymers are semi-crystalline and crystallinity and crystallite size decrease slightly with the comonomer content up to 10%, but the introduction of 20% comonomer leads to decrease the crystallinity markedly. The melting temperature of copolyesters decrease with the comonomer content, crystallization behavior altered and formation of pure crystals was hindered. However all copolyesters were able to form pure crystals, after annealing at 27oC for long time. It was also investigated that the elastic modulus decreases with the comonomer content. However, the elongation at break increases due to the decrease in crystallite size and crystallinity.

کلیدواژه ها:

copolyester ، poly(butylene adipate) ، bis(2-hydroxyethyl) terephthalate ، crystallization.