3. Processing and properties of agro-resourced materials for packaging

3.1 Forming processes

It is important that agro-sourced materials, including biocomposites, can be processed using conventional plastics processes (extrusion, injection, thermoforming, calendering) if they are to be used on an industrial scale.

In certain cases and depending on the application, the solvent route (casting) may be used.

The main limitation of some bioplastics is their thermal sensitivity, due to a melting temperature close to the degradation temperature, which can lead to polymer degradation during the processing. This is the case with bacterial polyesters (e.g. PHBV), whose two main thermal degradation reactions are well described in the literature: a random cleavage of polymer chains by cis-elimination, leading to a...