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Biobased polymers are considered as a promising alternative to conventional synthetic plastics from fossil fuels to recompense the draining resources for petroleum-based products, which addresses several environmental issues. Here, briefly, cellulose nanofibers were isolated from pineapple leaves and the quality of the prepared nanofibers was characterized using advanced instrumental technologies. Poor mechanical properties, barrier properties, and the hygroscopic nature are notable issues that reduce the shelf life of starch-based films, which can be rectified by the addition of nanoscale fillers. The impact of filler reinforcement on the films was investigated in different aspects. Morphology, UV shielding, wettability, and thermal degradation were carefully analyzed using polarized optical microscopy, UV-vis spectroscopy, static water contact angle measurements, and thermal gravimetric analysis, respectively. The water contact angle increases from neat TPS to nanocomposites with 3 wt% of CNF (41.25 0 to 51.77 0 ) and the water vapor permeability decreases from 7.32 to 5.68 Â 10 À2 g min À1 m À2 for 3 wt% CNF loading. Also, several enhanced properties were observed for the final product quality with respect to the reference sample, including that the potato starch/cellulose nanocomposite films were found to be UV resistant, and that higher transparency indicates the nanoscale dispersion. Further studies are anticipated to develop the materials on an industrial scale.

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Industrial sea food residues, mainly crab and shrimp shells, are considered to be the most promising and abundant source of chitin. In-depth understanding of the biological properties of chitin and scientific advancements in the field of nanotechnology have enabled the development of high-performance chitin nanomaterials. Nanoscale chitin is of great economic value as an efficient functional and reinforcement material for a wide range of applications ranging from water purification to tissue engineering. The use of polymers and nanochitin to produce (bio) nanocomposites offers a good opportunity to prepare bioplastic materials with enhanced functional and structural properties. Most processes for nanochitin isolation rely on the use of chemical, physical or mechanical methods. Chitin-based nanocomposites are fabricated by various methods, involving electrospinning, freeze drying, etc. This review discusses the progress and new developments in the isolation and physico-chemical characterization of chitin; it also highlights the processing of nanochitin in various composite and functional materials.

In this research work, we propose a synergistic effect of a green crosslinker and cellulose nanomaterial on the crystallinity, viscoelastic, and thermal properties of starch nanocomposites. A disaccharide derivative was used as a bio crosslinker and nanofiber from pineapple leaf as a reinforcing phase for starch. Sucrose was oxidised using periodate, that can selectively oxidise the vicinal hydroxyl group of sucrose and form tetra aldehyde derivative. Crystallinity of films after crosslinking decreased with successive addition of crosslinker. The melting temperature of films increased because of formation of more dense structure after crosslinking. Morphological investigations were analysed by atomic force microscopy. Polymer chain confinement and mechanics were quantified. The crosslink densities of the films were calculated using two models, phantom model and affine model, using storage modulus data. By using very low amount of crosslinker and nanoreinforcement, the properties of thermoplastic starch were significantly improved.

Cellulose nanofibers (CNFs) and nanocrystals (CNCs) are nanoscale materials obtained from nature by various physical and chemical treatments that has a strong reinforcing ability. CNFs and CNCs have different size, shape, viscosity, and other properties. This study focusses on comparative studies on reinforcing effect of CNFs and CNCs on thermoplastic starch (TPS). The nanocomposites with different weight percentage of reinforcing fillers are fabricated via solvent casting. The transparent TPS/CNF and TPS/CNC films are well characterized using dynamic mechanical analysis to study the effect of filler loading on viscoelastic behavior. All the nanocomposite films has better properties compared to neat TPS. But comparing the properties of CNFs and CNCs on the starch matrix, at some point of time, TPS/CNC composites are more transparent. But due to higher degree of entanglement, strong intermolecular attraction between starch and nanofibers, TPS/CNF composites are better, and the authors modeled the data with DMA and found that the nanofibers have better reinforcing ability and stress transfer character than CNCs. This type of comparative studies helps to find out the proper criteria to reinforce bio‐based material like starch for various applications.