Microcrystalline Cellulose Isolation – Proposed Mechanism: Enhanced Coupling

Cellulose-derived materials are an emergent opportunity for reducing the environmental impact of polymers. Microcrystalline cellulose (MCC) has increasing relevance in many sectors, including pharmacy, food, and reinforcement of polymers, but its application is limited by the low coupling between it and nonpolar polymers and the polar behavior of cellulose derivates. There is not a well-defined model for the isolation of MCC and the factors involved in the length and width, which are elements of high influence on the reinforcement effect of MCC. This study proposes a mechanism for the size reduction of cellulose fibrils isolated through acid hydrolysis and a post-plasma surface modification (PSM) to enhance coupling of the MCC with hydrophobic polymer matrixes. MCC was characterized by FTIR, XRD, and SEM before and after the plasma surface treatment with caprolactone, a biodegradable polymer. There were no changes in the FTIR spectra; however, in XRD the sample exhibited a decrease in intensity. These results suggest that PSM did not change the structure of MCC or chemical composition. However, an increase in the peak temperature of degradation confirmed the surface modification of MCC.