Isolation and characterization of corncob cellulose fibers using microwave-assisted chemical treatments

Cellulose fibers were obtained from corncob by using microwave-assisted chemical treatments (microwave-assisted alkaline pretreatment and microwave-assisted bleaching). These treatments efficiently removed the hemicellulose and lignin from the original corncob and increased the cellulose fiber content. The morphology, chemical structure, degree of crystallinity and thermal degradation characteristics of the resultant cellulose fibers were studied by using field emission scanning electron microscopy, Fourier transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. These microwave-assisted chemical treatments decreased the diameter of the cellulose fibers from 25-125 μm to 10-20 μm. The crystallinity of the corncob cellulose fibers increased from 32.7% to 73% due to the chemical treatments. The degradation temperature of the cellulose fibers was >260°C. The cellulose fibers obtained from these treatments can be used as biocomposites in reinforced polymer manufacturing.