Green Fabrication of Thermal-stable oxidized Cellulose Nanocrystals by Evolutive Fenton Reaction and In-Situ Nanoreinforced Thermoplastic Starch

Abstract High performances fiber and improved interfacial interaction can enhance the properties of polymer composites. Herein, microcrystalline cellulose (MCC) was oxidized by H2O2/CuSO4, a new Fenton process, to achieve oxidized MCC (OCNCs) with 16 ± 1% carboxyl content. Noteworthy, the thermal stability of OCNC was superior to CNC prepared by acid hydrolysis. Interestingly, the primary alcohol groups of MCC were selective oxidized and OCNCs achieved 11.0 nm, 231.6 nm and 72% of average diameter, length and degree of crystallinity, respectively. Then glycerol, starch and OCNCs were reactive extruded to fabricate TPS/OCNC bionanocomposites and their structure and performances were evaluated systematically. Strikingly, significant improvement in glass transition temperature (from 63.1 to 94.5 °C) and notch impact strength (from 1.3 to 3.9 kJ/m2) were noted for the amorphous TPS/OCNC with 1 wt% OCNC, and its tensile strength achieved 20.5 MPa, simultaneously. The improved mechanism of these performances was assigned to In-Situ forming “Carboxyl-Hydroxyl” hydrogen bonds which acted as the physically cross-linking interactions and improved the interfacial compatibility. We showcase Fenton reaction and reactive extrusion as the facile strategy to prepare sustainable and biodegradable TPS/OCNC bionanocomposites with properties more suitable for daily applications to replace petroleum-based plastic and eliminated the pollution of “microplastics.”