Potentially Biodegradable Short-Long Type Diol-Diacid Polyesters with Superior Crystallizability, Tensile Modulus, and Water Vapor Barrier

Long-chain aliphatic polyesters are potential biodegradable polymers having PE-like structure and properties. To develop biodegradable long-chain polyesters for practical applications, a series of short-long type long-chain polyesters, PEsxy (x = 2-4, 6, y = 10-16), are designed and synthesized from C-2-4,C-6 short-chain alpha,omega-diols and C10-16 long-chain alpha,omega-diacids via melt polycondensation. They showed intrinsic viscosity as high as 0.93-1.64 dL/g and PE-like crystal structure, rapid crystallization, and ductile tensile behavior. Their crystallization and melting temperature showed an increasing trend with diacid chain length and a clear odd-even effect. The highest melting temperature reached 94 degrees C, and the highest tensile strength reached 53 MPa. Chain length-dependent biodegradability in soil and hydrolytic degradation under neutral conditions at 30-60 degrees C was also observed. In comparison with the widely used biodegradable poly(butylene adipate-co-terephthalatae) (PBAT) copolyester, these polyesters show comparable tensile strength, ductility, and oxygen barrier performance, but obviously superior and desirable crystallizability, tensile modulus, and water vapor barrier performance.

Automated summary

Long-chain aliphatic polyesters with PE-like structure and properties were synthesized through melt polycondensation. They showed high intrinsic viscosity, PE-like crystal structure, and excellent tensile behavior. Long-chain polyesters exhibited chain length-dependent biodegradability and superior performance compared to PBAT copolyester.