Water-induced plasticization in vegetable-based bioplastic films: A structural and thermo-mechanical study

The possibility to use vegetable biomass, with minimal processing, as new green bioplastic for packaging is very appealing to mitigate environmental issues due to broad usage of conventional plastics. Here we developed vegetable bioplastic films from carrot pomace with good mechanical properties and glass transition temperature function of humidity, with a lowest value of −60 °C when highly hydrated. These properties were exploited to set-up scalable and green fabrication techniques for the production of macroscopic objects with elaborate shapes and detailed features at the micro scale. By means of a combination of techniques (FTIR, NMR, DSC and DMTA) we provide a comprehensive picture of the material structure and how the absorbed water changes the macromolecules’ structure, finally explaining the source of the glass transition of the material.