Cellulose extraction from red sage fiber, Prosopis Juliflora fiber, vegetable waste filler: Applications in PLA based bio composites

In this research, two natural fibers Red Sage Fiber (RSF) and Prosopis Juliflora Fiber (PJF) were extracted using water retting process and chemically treated for improving the properties. It was found with significant improvement in cellulose content for both RSF (60.75 %) and PJF (56.62 %) by NaOH treatment at 2 wt%. The surface treatment in natural fibers improved the tensile strength (TS) of RSF (133.4-161.8 MPa) and PJF (149.9-182.3 MPa). The Crystallinity index (Crl), Crystallite size (CrS) of 74.8 %, 4.3 nm was observed in vegetable waste filler (VWF) after acid and alkali treatments. The high concentration of fiber treatment (6 wt%) could create high porosity in the structure with surface deformations, decreasing the TS of PLA composites. The PJF up to 15 wt% increased the TS of composites from 50.24 to 51.71 MPa. All the combinations with PLA observed better TS than neat PLA. The incorporation of RSF (5-15 wt%) enhances the flexural strength (FS) (75.95-78 MPa). It was clearly observed significant reduction in water absorption property of PLA composites with increase in contact angle from 62° to 84° with treated filler.