Plant Cutin-Inspired Co- and Terpolyesters as Potential Packaging Materials

Petrochemical-based plastics are prevalent in the packaging industry. However, given their detrimental impact on the environment, alternatives for future packaging materials are necessary. In this work, the inspiration for creating new types of packaging materials was taken from plant cuticle structures in nature. Potential eco-friendly solutions could be derived from plants. We fabricated cuticle-like materials using molecules found in natural cutins. A cross-linked material was developed through the melt polycondensation of hexadecanedioic acid and glycerol and with the addition of hydroxy-hexadecanoic acid, a noncross-linked terpolyester was obtained. Both compression molding and casting techniques resulted in flexible and transparent/translucent films. Both polyester films showed very low direct UV transmittance, but noticeable total UV transmittance. These semicrystalline materials exhibited water vapor transmission rates that were comparable or superior to other polyesters, such as polylactide and polycaprolactone. An intriguing characteristic was the rough surface exhibited by the copolyester following compression molding, which closely resembled the wax layer structure seen in many natural peels.