A New Method for Developing Industrially Viable Nanocrystalline Cellulose-based Nanocomposites via Melt Compounding

Due to their high crystallinity and aspect ratio, bacterial cellulose nanowhiskers (BCNW) represent an appealing choice for the development of fully biobased nanocomposite materials with high barrier performance. However, their strong tendency to self-associate, together with their highly hydrophilic character, has restricted the production of nanocomposites containing cellulose nanowhiskers by industrial processing techniques such as melt compounding. This article presents an overview of the latest published results carried out within our group and also in other relevant literature, which have led to the development of an efficient strategy for the incorporation of highly dispersed BCNW by melt compounding through the use of electrohydrodynamic processing as a vehicle for the pre-incorporation of relatively high loadings of BCNW. First, a method for the production of highly crystalline and thermally stable BCNW was developed. These BCNW were incorporated into electrospun fibers, optimizing the process in terms of nanofiller dispersion and degree of incorporation. Finally, these hybrid fibers were used as masterbatches for the production of melt compounded nanocomposites, comparing their morphology and barrier properties with the conventional method of adding freeze-dried nanowhiskers. Th is method was proven to be effective for both hydrophilic and hydrophobic matrices and, thus, it provides a feasible route for the development of high barrier biobased materials.