Oxalic acid-mediated extraction of nanocellulose from corncob and its graft polymerization with methylmethacrylate for nanocomposite fabrication | |
| Author | Htet Wun Sandy |
| Call Number | AIT Thesis no.FB-24-05 |
| Subject(s) | Cellulose fibers Nanofibers Nanocomposites (Materials) |
| Note | A Thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Engineering and Bioprocess Technology |
| Publisher | Asian Institute of Technology |
| Abstract | Nano-fibrillated cellulose from biomass has recently gained attention owing to its biodegradable nature, low density, high mechanical properties, economic value, and renewability. However, its susceptibility to water is one of the drawbacks limiting nanocellulose applications in packaging industries. In this study, nanocellulose was extracted from corncob, agri-waste, by green and sustainable mild oxalic acid. Followed by modification of hydrophobicity by graft polymerization of methyl methacrylate, using ceric ammonium nitrate as an initiator. The films were developed by incorporating hydrophobic suspension of nano-fibrillated cellulose. The study demonstrated the successful preparation of nanocellulose from corn cob using oxalic acid hydrolysis and its incorporation into nanocomposite films via MMA graft polymerization. Optimized hydrolysis conditions, predicted by Response Surface Methodology (RSM), yielded 84.73% nanocellulose, validating the model with a predicted value of 85.31%. The grafting process showed high efficiency, achieving a maximum yield of 36.27%. The mechanical properties of the films were significantly enhanced by incorporating cellulose nanofibers (CNFs) and modified cellulose nanofibers (MCNFs). Films without CNF or MCNF had a tensile strength of 1.03 ± 0.05 MPa and an elongation at break value of 1.52 ± 0.08, whereas films with 5% CNFs showed the highest tensile strength of 1.86 ± 0.07 MPa and an elongation at break value of 1.14 ± 0.002. Increased CNF content (10%) and MCNF (5% and 10%) led to decreased tensile strength but increased elongation at break, indicating the importance of optimizing nanocellulose content to avoid phase separation and poor particle distribution. The films exhibited improved hydrophobicity, with enhanced water contact angles and absorption times, particularly in MCNF-reinforced films, which also showed superior water stability and reduced water vapor permeability. This research highlights the potential for using sustainable methods to produce high-performance nanocomposite films from agricultural waste, offering significant environmental and material innovation benefits. |
| Year | 2024 |
| Type | Thesis |
| School | School of Environment, Resources, and Development |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Loc, Thai Nguyen |
| Examination Committee(s) | Anal, Anil Kumar;Salin, Krishna R. |
| Scholarship Donor(s) | AIT Scholarships |
| Degree | Thesis (M. Sc.) - Asian Institute of Technology, 2024 |