Biobased Poly(ethylene succinate)-b-poly(triethylene terephthalate) multiblock copolyesters with high melting temperature and improved crystallization rate and mechanical property

Biobased poly(ethylene succinate)-b-poly(triethylene terephthalate) (PES-b-PTEGT) multiblock copolyesters with low weight ratios of PTEGT segment were successfully synthesized from dihydroxyl terminated PES and dihydroxyl terminated PTEGT prepolymers in this work through a chain extension reaction. The thermal, crystallization, and mechanical properties of PES-b-PTEGT were systematically investigated and compared with those of PES also prepared via the chain extension method. Two glass transition temperature (Tg) values were detected for PES-b-PTEGT, corresponding to the Tg of PES segment and that of PTEGT segment, respectively. PES-b-PTEGT showed a high melting temperature of around 100 degrees C and a thermal decomposition temperature of above 320 degrees C. The crystallizability of PES segment in PES-b-PTEGT was obviously enhanced under different crystallization conditions, which was attributed to the interface-assisted crystallization. In addition, the mechanical property (including both the elongation at break and the tensile strength) of PES-b-PTEGT was also remarkably improved. The synthesis of PES-b-PTEGT with a high melting temperature, faster crystallization rate, and improved mechanical property provided a new modification method to improve the physical property and extend the practical application of biodegradable polyesters.

Automated summary

In this study, biobased poly(ethylene succinate)-b-poly(triethylene terephthalate) (PES-b-PTEGT) multiblock copolyesters with low weight ratios of PTEGT segment were successfully synthesized using a chain extension reaction. The thermal, crystallization, and mechanical properties of PES-b-PTEGT were systematically investigated and compared with those of PES prepared via the chain extension method. PES-b-PTEGT exhibited high melting temperature, enhanced crystallizability, and improved mechanical property.