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This work aimed to study the tribological behavior of films composed of mixtures of nanofibrillated cellulose (NFC) and microcrystalline cellulose (MCC) at different concentrations. A microabrasive wear resistance analysis is presented as part of the tribological properties. Tribological behavior was observed against wear and tear in dry conditions. Mean surface roughness (Ra) was directly influenced by MCC concentrations in films, reaching values up to three times higher at concentrations of 30% MCC compared to films without MCC. The specific wear rate (k) of the films was inversely proportional to the MCC concentrations, observing that for low concentrations of MCC (5%), the reduction of wear was only 7% for films without MCC. Concentrations of 10% MCC the wear rate was reduced by 52%, and when passing to concentrations of 30% MCC, the reduction of wear was even more abrupt up to 95%. The specific wear rate obtained was favorable and comparable to films of synectic origin, which shows that NFC/MCC composites may offer tribological advantages such as reinforcement coatings on different materials.

Background: In the study of biologically-based materials, nanocelluloses have been showing great prominence and positioned themselves as promising alternatives for the production of different industrialized materials. This polymer has received significant attention recently because it is produced from renewable sources and has unique properties offered by its organic nature and semi-crystalline structure. This work aimed to study the structural properties of suspensions and films by increasing MCC concentration in the form of powder with variations of 5 % (m/m) from 5 % to 30 %. Results:As expected, incorporating MCC increased the Segal index. The morphological analysis showed an increase in the diameters of the structures (NFC / MCC) in the suspensions when the presence of MCC was more significant, and films with cluster formations were observed. The films showed air permeability. Due to the MCC increase, the surface charge had results close to electrostatically stabilized nanosuspensions. An increase in the resistance to thermal degradation of the films was also observed. Conclusion:NFC has promising properties for different applications; it provides a film with a stable structure and is resistant to oxygen and tensile stresses. In addition, MCC has excellent potential due to its high crystallinity, structural characteristics, and nature. The increase of the MCC content altered the properties of the suspensions and films produced with NFC, forming a cohesive and resistant film, and influencing the performance of the different properties of the materials evaluated in this study, like air permeability, suspension stability, and thermal resistance.