Characterization of ligno-cellulosic fiber extracted from Atriplex halimus L. plant

Extraction and characterization of novel fibers from Tecoma stans Linn bark for use as reinforcement in polymer composites

Embarking on a pioneering investigation, this study unravels the extraordinary qualities of Tecoma stans Fibers (TSFs), freshly harvested from the rachis, establishing them as prospective reinforcements for biocomposites. Delving into their intricate characteristics, TSFs exhibit a unique fusion of physical resilience, with a density of 1.81 ± 0.39 g/cc and a diameter of 234.12 ± 7.63 μm. Complementing their physical prowess, their chemical composition boasts a harmonious blend of cellulose (70.1 ± 9.06 wt%), hemicellulose (13.56 ± 4.29 wt%), lignin (7.62 ± 2.39 wt%), moisture (4.21 ± 1.56 wt%), wax (2.37 ± 0.63 wt%), and ash (1.25 ± 0.36 wt%). In the realm of mechanical strength, TSFs showcase an impressive tensile strength of 639 ± 18.47 MPa, coupled with a robust strain at failure of 1.75 ± 0.13 % and a Young Modulus of 36.51 ± 1.96 GPa. Unveiling their crystalline intricacies, these fibers reveal a microfibril angle of 14.66 ± 0.15°, a crystalline index (CI) of 63.83 %, and a crystallite size (CS) of 9.27 nm. Beyond their mechanical marvels, TSFs exhibit unwavering thermal stability, enduring temperatures up to 297.36 °C, with a Tmax reaching an impressive 392.09 °C.

Extraction and characterization of novel natural fiber from Centaurea melitensis plant

In this work a new cellulosic fibers extracted from Centaurea Melitensis plant to the prospect of employing them as a source of reinforcement in composite materials. In this investigation, morphological, chemical, physical and mechanical features of Centaurea Melitensis fibers are investigated. The morphological characteristics using anatomical technique and scanning electron microscopy revealed the presence of a large percentage of fibroblasts in the fibers that allow adhesion with the matrix when manufacturing of composite materials. The fiber density is 1.269 ± 0.018 g/cm3 and the diameter is 187.11 ± 60.41 μm depending on the physical properties. The chemical properties revealed that the Centaurea Melitensis fiber has a crystalline size of 16.92 nm and a crystallinity index of 47.69% using XRD. The results of FTIR analysis proved on major components such as cellulose, hemicelluloses and lignin, by TGA the thermal stability was found up to 210°C and the maximum temperature up to 317.86°C. The mechanical properties have shown that the value of the tensile strength of the fibers is 336.87 ± 59.94 MPa, Young’s modulus is 23.87 ± 5.21 GPa, and the strain at failure is 1.27 ± 0.36%, and the interfacial shear strength is 9.82 ± 2.35 MPa. The statistical approach, Weibull distribution was used with two and three parameters to examine the experimental data due to their dispersion. WEIBULL statistical analytical test was used with 2 and 3 parameters are used to examine the experimental data due to their dispersion. All the findings from this investigation reveal that Centaurea Melitensis fibers can be a qualified candidate to be used as reinforcement in low density composite materials.

Extraction and characterization of natural lignocellulosic fibres from Typha angustata grass

In recent years, efforts have been made to reduce deforestation to conserve the ecosystem. In the current scenario, agro-cultivated products are used instead of wood for engineering applications. Thus, natural lignocellulosic fibres are used as a reinforcing material and have been extremely attractive to industries and the scientific community during the past few decades. This study aimed to examine the use of natural fibres extracted from Typha angustata grass as reinforcement in polymer matrix composites. The density of the fibres was 1.015 g/cc. Chemical analysis confirmed that T. angustata fibres (TAFs) have a cellulose content of 73.54 wt%, a hemicellulose content of 10.11 wt%, a lignin content of 6.23 wt% and a wax content of 0.23 wt%. The crystallinity index (65.16 %) and crystalline size (6.40 nm) were identified by X-ray diffraction (XRD) analysis. The presence of functional groups in the TAFs was examined by employing Fourier-transform infrared spectroscopy (FTIR). The presence of cellulose at peak intensities of C2, C3 and C5 in the TAFs was confirmed using ¹³C nuclear magnetic resonance (NMR) spectroscopy. The single fibre tensile test revealed that the tensile strength was 665 ± 7 MPa and Young's modulus was 27.45 ± 3.46 GPa. The thermal stability of the TAFs was examined by thermogravimetric analysis (TGA), and the prominent peak was observed at 298.48 °C, with a kinetic activation energy of 67.99 kJ/mol. The surface roughness of the fibres was analysed by atomic force microscopy (AFM) with an accuracy of 1 nm. The above-mentioned outcomes indicated that the TAFs have desirable properties that are comparable to existing natural fibres and suggested to be utilised as the possible reinforcement to fabricate the fibre-reinforced polymer matrix composites.

Phytofabrication of bimetallic silver-copper/biochar nanocomposite for environmental and medical applications

In the current study, a novel, green, low-cost, and sustainable path for the phyto-fabrication of Ag-Cu biochar nanocomposite (Ag-Cu/biochar) by Atriplex halimus biomass and aqueous extract is described. Surface plasmon resonance peaks were detected at 450 nm and 580 nm signifying the formation of both silver and copper nanoparticles, respectively on the biochar surface. XRD analysis confirmed the crystal structure of the phytosynthesized Ag-Cu/biochar whereas FT-IR, SEM, EDX, and XPS analyses confirmed the successful phytofabrication of the composite. Ag and Cu nanoparticles loaded on the biochar surface were almost spherically-shaped with a particle size ranging from 25 nm to 45 nm. Zeta potential of -25.5 mV showed the stability of Ag-Cu/biochar. The potential of this novel nanocomposite in the removal of doxycycline (DOX) was evident under different conditions as it reached nearly 100% under the optimum reaction conditions (DOX concentration; 50 ppm, pH; 9, a dose of Ag-Cu/biochar; 0.01 g, temperature; 25 °C, and H₂O₂ concentration; 100 mM). The promising regeneration of Ag-Cu/biochar was evident as the removal efficiency was 81% after 6 consecutive cycles. Ag-Cu/biochar was also shown an excellent antimicrobial activity against gram-negative bacteria as well a promising antioxidant activity.