Dimerization of fatty acids mainly C18 vegetable unsaturated fatty acids like oleic or linoleic acid is triggering increasing attention in sustainable polymer chemistry. Subsequent hydrogenation or reduction of C18 fatty acids yields difunctional monomers: fatty dimer diols or fatty dimer acids characterized by low glass transition temperature, amorphous structure, and high conformational flexibility of aliphatic chains. They are attractive biobased components to create soft segments within copolyesters due to the low cohesion energy (2.85 kJ mol -1 ) which gives the ability of free rotation of carbon-carbon bonds (the energy barrier of the rotation of carbon-carbon bonds is 12.6 kJ mol -1 ). It was already proved in our previous studies where enzymatic synthesis of poly(butylene succinate)-co-(dilinoleic succinate) multiblock copolyesters was performed, and where dilinoleic diol (DLD) being a dimerized fatty acid derivative was used as a building block to create soft segments. Notably, study by Kwiatkowska et al. demonstrated the synthesis of 2,5-poly(butylene furanoate) catalyzed by organometallic catalyst with variable content of DLD indicating successful direct esterification of FDCA with 1,3-propanediol and subsequent copolymerization with DLD. Interestingly enough, in recent work, Nasr et al. conducted enzymatic polycondensation reactions using diethyl 2,5- furandicarboxylate, 1,4-butanediol, 1,8-octanediol, and Pripol™ 2033 in their work. They referred to Pripol™ 2033 as fatty dimer diol in their study, while in this work, the same compound is referred to as dilinoleic diol (DLD). The study revealed that the addition of Pripol™ 2033 enhanced the polycondensation reaction in systems that contained high furan content and 1,4-butanediol, which otherwise did not produce any high molecular weight products. The primary objective of this research is to broaden the scope of polyester materials that can be synthesized from renewable resources by employing CAL-B as a biocatalyst and to deliver a comprehensive characterization of novel furan-based block copolyesters. Specifically, the investigation will delve into the influence of diol chain lengths (C = 6, 8, 10, 12) in alkyl furanoate hard segments, examining their impact on synthesis efficiency, crystalline structure, and thermal properties of poly(alkyl furanoate-co-dilinoleic furanoate) copolyesters with a 70-30 wt% ratio of hard to soft segments. Moreover, the resulting materials underwent thorough assessment for their potential applicability as eco-friendly packaging materials in the medical sector to create "sterile barrier system" (SBS), where allowing sterilization, providing an acceptable microbial barrier and allowing aseptic presentation are of paramount importance 36. Medical packaging must strike a balance between offering robust physical and barrier properties to protect enclosed medical devices from microorganisms and external contaminants, while still facilitating the transmission of sterilizing agents such as ethylene oxide. Furthermore, oxygen plays a critical role in effective ventilation of the residual ethylene oxide, making oxygen transmission rate measurements an essential part of the study.