Patwa, Rahul2019-07-152023-10-192019-07-152023-10-192018ROLL NO.126107030https://gyan.iitg.ac.in/handle/123456789/1260Supervisors: Vimal Katiyar and Amit KumarEnvironmental hazards caused by conventional plastics having fossil-fuel origin have aroused interest in bio-based polymers. Poly(lactic acid) (PLA) has rapidly gained popularity in the past decade as potential replacement for petroleum-based plastics. Attributes like biodegradability, recyclability, compostability, biocompatibility and non-toxicity is what makes PLA the eco-friendly alternative. However, several drawbacks are associated with PLA such as brittle nature, slow crystallization and poor gas barrier properties which avert its utilization for food packaging applications to its full potential.An effort has been undertaken in the current doctoral research work to address these limitations by fabrication of PLA based bionanocomposites.In the current work, the effect of novel discotic bio-filler crystalline silk nano-discs (CSNs) on the structural, morphological, thermo-mechanical, optical and barrier properties of PLA is investigated. CSNs are extracted from waste Muga silk through novel hydrolysis cum sonication route providing an effective strategy for upconversion of ‘waste to wealth’. The physico-chemical, structural and morphological properties of the isolated CSNs are studied. The CSNs are having a predominant β-pleated sheet conformation which was confirmed using FTIR, Raman and NMR studies. The average diameter and thickness of CSNs calculated using AFM, TEM and FESEM is 49.1±12 nm and 3.1±0.9 nm, respectively. Amino acid analysis shows that CSNs are mainly composed of alanine, serine and glycine which are 83.8%, 6.8% and 6.1%, respectively which makes CSNs hydrophobic in natureenCHEMICAL ENGINEERINGThesis