Laccase-Enzyme Treated Flax Fibre for Use in Natural Fibre Epoxy Composites

PP/Jute Fiber Composites: Effect of Biological Route of Surface Treatment and Content of Jute on Composites

Jute as a fiber has many applications. It is also used in polymers as reinforcement due to its good tensile properties. However, when it is used in polymer matrices, there is a lack of adhesion between the polymer and jute fiber. Surface treatment of fiber using chemicals has been found to improve the properties. However, the use of chemicals causes environmental pollution, when these chemicals are discharged into the environment. In this paper, an attempt has been made to study the effect of the biological route to surface treat the jute fiber. The effect of surface treatment on the morphology of jute was examined. A comparative study was on the crystalline, thermal, and tensile fracture morphology of the composites to understand the effect of the incorporation of untreated and treated jute fibers in polypropylene (PP).

Retting of banana pseudostem fibre using Bacillus strains to get excellent mechanical properties as biomaterial in textile & fiber industry

Banana pseduostem (BP) fibre, sometimes known as banana fibre, is a new natural fibre with potential commercial applications in the textile and fibre industries. Softening these fibres might enhance their mechanical qualities, allowing them to be used in more textile applications. The current research looks at the softening of banana fibres (Musa paradisiaca L) utilising a variety of chemical (NaOH & HCl) and bacterial treatments. Physical (Hygroscopicity, Density, Linear density), chemical (cellulose, Hemi-cellulose and Lignin) and mechanical parameters (Peak load, Breaking Elongation, Tenacity) of the treated fibres were measured as per normal technique with raw banana fibres. The tenacity (g/tex) of microbial treated (Bacillus licheniformis) (7 days) fibre was found to be greater, at 6.33, but the average peak elongation (%) of (Bacillus Subtilis) was found to be higher, at 8.2. The lignin % of untreated Banana fibres (15.98%) was reduced in fibres treated with 5N of NaOH (10.75%), 5N HCl (8.73%), Bacillus aryabhattai (11.4%), Bacillus licheniformis (12.54%) and Bacillus Subtilis (13.56%). In contrast to raw banana fibre, the mechanical qualities of treated fibres showed incremental results. Finally, the study found that treating banana fibre with NaOH, HCl and Bacillus sp. had a substantial impact on the physiochemical parameters. SEM and FTIR methods were used to validate the efficiency of the bacterial treatment.

The mechanical properties of alkali and laccase treated pterocarpus angolensis (mukwa)-polylactic acid (PLA) composites

The desire of producing marketable green bio-composites displaying good functional properties has increased. Biodegradable composites are a subject of interest as they respond to ecological concerns. In this study, an eco-friendly alkali-laccase modification was used to improve the interfacial adhesion of mukwa wood fiber and polylactic acid (PLA) matrix. The untreated and treated mukwa-PLA composites were fabricated via extrusion and compression molding technique and investigated. The mukwa wood fibers and mukwa-PLA composites were characterized by chemical composition, crystallite size, Fourier transform infrared spectroscope (FTIR), mechanical properties, and scanning electron microscope (SEM) respectively. The cellulose content was found to increase, while the hemicellulose, lignin, and extractives reduced after the surface modifications. The alkali-laccase, laccase, and alkali modifications increased the tensile strength of the untreated/PLA composites by 12.3 %, 5.2 %, and 3.8 % respectively. The flexural strength of the composites reached a maximum of 95.1 MPa following the alkali-laccase treatment. The alkali-laccase treated composites showed increased impact strength of 53.9 % on the untreated/PLA composites. Good correlations between the crystallite size and the mechanical properties were reported, with the highest R-square (R²) value of 1 found between the impact strength and crystallite size. The modifications strengthened the interaction between mukwa and PLA as more voids, fiber pull-outs, and debonding characteristics were observed on SEM microstructures of untreated/PLA.