Isolation and characterization of microfibrillated cellulose and nanofibrillated cellulose with "biomechanical hotspots"

Waste biomass of two major milk weeds was separately given combination of chemical-mechanical treatments in order to expose natural cellulosic micro and nano-fibrillated structures (MFCs and NFCs). Compositional and FTIR analysis were initially used to confirm the removal of impurities. WA-XRD and FESEM analysis of MFCs further revealed presence of highly crystalline, fine-shaped materials that resemble carbonaceous structures. HR-TEM analysis further exposed morphology of the two nanofibrils possessing a well entangled network (diameter <= 80 nm) comprising coil shaped fine spots of size up to 80 nm-220 nm. Morphology even got clearer when STEM and EDX mapping of the NFCs assured that observed fine-spots are integral and possibly due to certain biosynthetic process. Presence of calcium elements in two types of NFCs provided important evidence of exposure of nanocellulose-xyloglucan-pectin configuration responsible for coil-shaped fine-spots resembling "biomechanical hot spots".