In such a comparison, two main variables need to be accounted for, crystallinity and chain mobility. Polymer crystals can be considered impermeable to water, they increase the path length of the permeating water molecules and they reduce the mobility of the amorphous phase where the diffusion takes place. Meanwhile, the presence of hydrophilic functionalities increases water solubility and makes the resulting polymer susceptible to plasticization, increasing chain mobility and thus facilitating water diffusion. Crosslinking also reduces the overall chain mobility which can reduce the water permeability. The semi-crystalline nature of PLA and PCL contributes to their water barrier properties while the short starting monomers (C3 and C6, respectively) result in a high oxygen-to-carbon ratio and thus a final material with moderate hydrophilicity. By using longer monomers (C16) based on cutin, Polisetti et al. produced a semi-crystalline polyester with a WVTR of 650 ± 100 g μm day -1 m -2 showing how the increased hydrophobicity yields a lower water vapor transmission rate. Thus, long suberin monomers have too the potential to produce materials with low WVTR. *Calculated using information from the reference.