Combination of the microfibrillated cellulose and bioplastics for new thin barrier and thermosealable layer onto paper for new sustainable packaging solution

Applications of bio-based materials in the sustainable packaging industry have shown strong growth due to recent trends in the consumer market moving toward greener packaging. Over the past few years, new policies, regulatory frameworks, and standards adopted worldwide enhance and implement the circular economy and bioeconomy. Within this framework, an excellent candidate for new high performance biobased materials is nanocellulose. Specifically, microfibrillated cellulose (MFC) brings advantages in strength enhancement, light-weighting and barrier properties. By using MFC, it is possible to reduce the package’s total weight, develop films featuring excellent barrier against gases like oxygen and even grease and oil, and at the same time reduce CO2 footprint by replacing aluminum and plastic film in packaging.
In this regard, the MFC wet lamination process, recently developed, can assemble a layer of MicroFibrillated Celluloses (MFC) onto the fibre based materials without the use of glue. The MFC layer is thin enough to be economically relevant and thick enough to get the barrier performance. Some challenges still exist for this material to exploit in the packaging industry like the sealability among others. Currently, the usual heat-sealable closure of the packaging is made of polyethylene based solutions.
This project proposes solutions to formulate heat-sealable MFC suspensions and to shape wet multilayer MFC to produce barrier and heat-sealable sustainable packaging. The aim is to formulate heat-sealable MFC suspensions from bioplastic materials. The main subjects studied are: (i) the process formulation of heat-sealable MFC by adding different bioplastic (e;g PLA, PHBH) via different strategies (In situ during the fibrillation orafter), (ii) the impact of additives on the film forming and stability of MFC suspensions, and (iii) the characterization of the heat-seal strength of wet-laminated MFC sample. Promising results were obtained with a specific combination of PLA and MFC.