• Polyesters PEs5y with high intrinsic viscosity were successfully synthesized via polycondensation of PeDO and C 10-16 α,ω -diacids. • These long chain polyesters have T m up to over 70 °C and PE-like thermal and mechanical properties. • The T m , T c , crystallizablity, tensile modulus and gas barrier show increasing trend with chain length of diacid. • Odd-odd type odd-even effect was observed for the thermal properties. • These potentially biodegradable polyesters manifest crystallizability, tensile modulus and water vapor barrier performance superior to PBAT. Several aliphatic long chain polyesters with intrinsic viscosity of 0.80-1.47 dL/g were synthesized from biobased 1,5-pentanediol and long chain α,ω-diacids with 10-16 carbon atoms. Their chemical structure was characterized, and thermal, mechanical and gas barrier properties were assessed. These long chain polyesters have a melting temperature higher than poly(ε -caprolactone) and manifest polyethylene-like rapid crystallization, good thermal stability and ductile tensile behavior. Their melting temperature, crystallizablity, tensile modulus and oxygen and water vapor barrier performance all increase with increasing the chain length of diacid. In comparison with the widely used biodegradable poly(butylene adipate-co-terephthalate) copolyester, these potentially biodegradable polyesters show comparable tensile strength, ductility and oxygen barrier performance, but obviously superior crystallizability, tensile modulus and water vapor barrier performance. [ABSTRACT FROM AUTHOR]