Nanocellulose has emerged as a versatile, bio-based, and eco-friendly material due to its high transparency, excellent mechanical properties, and biodegradability, positioning it as a promising alternative for sustainable packaging. In this study, we present a mild, acid-free extraction method to obtain high-crystallinity nanocellulose from underutilized Walikukun fiber (WF) using sequential alkali treatment, bleaching, and mechanical sonication. Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) confirm the effective removal of lignin and hemicellulose, resulting in a crystallinity index of up to 91.61% and the formation of densely packed cellulose fibrils. Thermogravimetric analysis reveals enhanced thermal stability, partly attributed to oxidation and structural modifications induced by sonication. Overall, WF-derived nanocellulose demonstrates potential as a sustainable alternative to petroleum-based polymers, offering improved barrier properties, thermal stability, and optical clarity for eco-friendly packaging. This work highlights the environmental benefits of using renewable natural fibers, thereby contributing to circular economy objectives and reducing dependence on nonrenewable resources.

Environmentally sustainable polymer composites utilizing agro-waste biofillers provide a responsible method for improving thermoplastic performance. This work involved the fabrication of low-density polyethylene composites supplemented with Syzygium cumini seed biofillers using injection molding, utilizing filler loadings of 0, 10, 20, 30, and 40 wt%. The mechanical, physical, thermal, and morphological qualities were extensively assessed. The findings indicated that mechanical performance enhanced with rising filler content, peaking at 20 wt% Syzygium cumini, where the composite had a tensile strength of 6.58 MPa, an elastic modulus of 31.4 MPa, and a Shore D hardness of 42. The density grew significantly with the addition of filler, showing the successful assimilation of the biofiller. Dynamic mechanical investigation indicated superior stiffness retention at 20 wt% Syzygium cumini, whereas 10 wt% Syzygium cumini exhibited higher damping characteristics. Fourier-transform infrared spectroscopy and Energy-dispersive X-ray spectroscopy investigations validated the existence of lignocellulosic functional groups and bio-derived elemental composition, whereas scanning electron microscopy observations revealed homogeneous filler dispersion at optimal loading levels. Syzygium cumini seed particles are an economical and sustainable reinforcing filler for low-density polyethylene, with 20 wt% determined as the ideal reinforcement concentration.

Abstract In this work the effect of pultrusion process variables i.e. pultrusion die temperature, speed of pulling, and % of a hybrid bio filler (calcium carbonate (CaCO3), bagasse fiber, and carbon black (CB)) on the characteristics of pultruded glass fiber reinforced polymer (GFRP) composites is discussed. The response parameters, namely ultimate tensile and flexural strength, hardness, and % shrinkage were analyzed to realize the effect of pultrusion process parameters. A Taguchi L9 orthogonal array was used for single response optimization, and gray relational analysis for multi-response optimization. Results show that pultruded GFRP properties are significantly influenced and improved by optimizing the selected process parameters. An improvement of 31%, 6.5%, and 14.6% is achieved in ultimate tensile strength, flexural strength, and hardness respectively in comparison to result reported in earlier work by the authors. Results show that process optimization effectively enhances the performance, making them suitable for lightweight forearm protection applications.

Depleting global energy resources and the escalation of environmental problems have driven the development of novel cellulosic fibers for sustainable polymer composites. This study investigates the extraction and performance enhancement of the natural cellulosic fibers obtained from the stems of Pennisetum purpureum Schumach. and explores the potential application as reinforcement fibers in the sustainable polymer composites. The extracted Pennisetum purpureum Schumach. fiber (PPF) was subjected to alkali treatments of varying concentrations, namely, 1, 5, 9, and 13 wt%. The effects of alkali concentration on the comprehensive properties of raw and treated PPFs was systematically investigated. Results demonstrate that the cellulose content of the treated PPFs raised, whereas hemicellulose content decreased after the alkali treatment. Scanning electron microscopy analysis reveals that the treated PPFs exhibit a textured surface, with partial exposure of fiber bundles. Water contact angle and water absorption rate decreased by 6.7%-45.5% and 9.56%-15.75%, respectively, after alkali treatments. Fourier-transform infrared spectroscopy confirms that hemicellulose and lignin components were effectively dissolved from the surface of the plant fiber. X-ray diffraction result indicates that the sodium hydroxide treatment significantly raised the crystallization properties of the PPFs, with the crystallinity index rising from 44.43% to 52.27% and the crystalline size improving from 2.00 to 1.88 nm. Thermal stability analysis reveals that the maximum thermal stability temperatures of the PPFs raised from 260 degrees C to 280 degrees C, and the mechanical properties of the treated PPFs enhanced from 62.43 to 117.92 MPa and 6.27 to 9.60 GPa, respectively, after the alkaline modification. These findings confirm that the PPFs treated with an appropriate concentration of sodium hydroxide is the most suitable reinforcement fibers for the structure of sustainable polymer composites.

Natural fibers are increasingly being explored as sustainable alternatives to synthetic reinforcements in polymer composites; however, their inherent hydrophilicity, and poor interfacial compatibility with polymer matrices limit their engineering applications. Bauhinia purpurea L. (BP) fiber possesses promising characteristics for composite reinforcement, yet a systematic optimization of alkali treatment to enhance its performance has not been previously reported. This study hypothesized that controlled NaOH treatment could effectively modify the fiber surface by removing amorphous constituents, thereby improving its characteristics. Accordingly, BP fibers were treated with NaOH concentrations of 5%, 10%, 15%, and 20%, followed by comprehensive physical, chemical, crystallographic, thermal, mechanical, morphological, and surface topography characterization to identify the optimum treatment condition. Among these, the 15% NaOH-treated BP fibers exhibited the most balanced combination of properties, indicating its strong potential as reinforcement for sustainable polymer composites. The optimum 15% NaOH treatment produced fibers with a tensile strength of 498.26 MPa, and tensile modulus of 6.58 GPa. It contained 73.02% cellulose, 7.62% hemicellulose, 19.41% lignin, 0.62% wax, 9.57% moisture, and 2.54% ash, while exhibiting improved thermal stability up to 230 °C and reduced water absorption compared with untreated fibers. SEM and AFM analyses revealed a cleaner and rougher fiber surface following alkali treatment, which is expected to enhance mechanical interlocking and promote improved fiber-matrix interactions in composite systems. Overall, the findings demonstrate that controlled alkali treatment (15% concentration), substantially enhances the intrinsic properties of BP fibers and establishes a strong foundation for their future utilization as reinforcement in environmentally sustainable polymer composites.

A polyvinyl alcohol (PVA) film loaded with Centella Asiatica (CA) extracts was made for wound healing applications. The film was produced using solvent casting and analysed for its phytochemical, chemical compositions, morphology, mechanical properties, drug release, and biocompatibility. The HPLC showed that quercetin and other active ingredients were present, and FTIR confirmed strong hydrogen bonding between CA and PVA. The degrees film displayed a contact angle of 86.60 , indicating hydrophilicity crucial for cellular attachment and moisture retention. Mechanical testing revealed a tensile strength of 3.54 MPa and an elongation of 17.09 %, confirming the film's durability and flexibility. The film demonstrated 91 % wound healing at a concentration of 100 mu g/mL, and cell toxicity tests revealed that more than 88 % of the cells remained alive, indicating high compatibility with living tissue. In vivo confirmation showed rapid wound contraction, whereas histological investigation revealed substantial collagen deposition and fibroblast proliferation in the treated groups. The drug release profile demonstrated a biphasic pattern characterised by anomalous (non-Fickian) diffusion behaviour. These results highlight the CA-PVA film as a promising wound dressing with suitable biological activity, biocompatibility, and mechanical strength.

This review aims to critically investigate the swelling behavior of natural fiber-reinforced composites (NFRCs), with a focus on identifying key mechanisms of moisture absorption, the influence of fiber–matrix interactions, and the effectiveness of mitigation strategies such as chemical treatments and hybridization. A systematic synthesis of over 120 peer-reviewed articles published between 2015 and 2025 was conducted. These studies were analyzed to extract data on moisture uptake behavior, microstructural evolution, treatment effects, matrix properties, and performance under various environmental conditions. The review identifies cellulose crystallinity, hemicellulose content, and fiber–matrix interfacial bonding as dominant factors influencing swelling. While Fickian diffusion models describe early-stage absorption, long-term exposure often results in non-Fickian behavior due to matrix plasticization and interface degradation. Chemical treatments such as alkali, silane, and acetylation reduce water absorption but may compromise fiber strength if overapplied. Hybridization with hydrophobic fibers and the use of non-polar matrices improve resistance. Moisture-induced performance degradation is strongly influenced by environmental variables such as temperature, humidity cycling, and salt fog. This review consolidates current knowledge on swelling mechanisms in NFRCs and clarifies the trade-offs between moisture resistance and mechanical performance. It also proposes design guidelines and testing protocols for enhancing long-term durability. The findings are applicable to industries seeking sustainable yet durable composite materials, particularly in automotive, construction, marine, and packaging sectors where environmental exposure is a critical concern.

This study involved synthesizing nanolubricants by incorporating Sm2O3 into SAE20W40 base lubricant. The effects of different desiccation times after surface modification with stearic acid were analyzed. Five different weight percent concentrations of SAN12, SAN24, and SAN36 particles were added to the base lubricant. The physicochemical properties of the synthesized nanolubricants, including calorific value, flash point, fire point, and viscosity, were investigated. Dispersion stability, bond analysis, acid value, and thermal stability were also evaluated for these nanolubricants. Subsequent research involved evaluating the tribological characteristics of these nanolubricants using a pin-on-disc tribometer and four-ball tester. The pin-on-disc test exhibited a decreasing trend, with a maximum reduction of 40% in coefficient of friction and a 69.9% decrease in wear rate. Subsequently, as the concentration increased, values began to rise. In four-ball testing, a 34.2% decrease in coefficient of friction was observed.

In recent years, researchers have been concerned with hybrid laminated polymer composites reinforced with natural fibers (NF) and synthetic fibers (SF). NF/SF hybrid laminated composites (HLCs) offer several benefits, including tailored mechanical properties, low weight, eco-friendliness, low moisture absorption, and ultraviolet (UV) radiation resistance. This review focused on fibers selection, stacking sequences, and ply orientation, which influence the mechanical properties, such as tensile, flexural, impact, fatigue, low-velocity impact (LVI), failure modes, and fracture behaviours of NF/SF HLCs. This review also covers various non-destructive testing (NDT) methods used to evaluate the mechanical properties, failures, and damage in NF/SF HLCs. This review also reveals the role of artificial intelligence (AI) in optimizing the mechanical properties and damage prediction of NF/SF HLCs. The environmental effects, durability behaviour, and life-cycle analysis (LCA) of NF/SF composites are analysed along with their applications. Furthermore, a comprehensive patent landscape analysis and future perspectives of HLCs are presented.

Natural fiber reinforced polymer composites are gaining prominence as sustainable, biodegradable alternatives in modern engineering. However, challenges like moisture absorption and poor thermal/electrical performance persist. Chemical fiber treatments can mitigate these issues. Among natural fibers, basalt stands out for superior mechanical properties, making basalt fiber-reinforced polymer (BFRP) composites increasingly vital. This study enhances BFRP performance by incorporating tungsten carbide (WC) ceramic nanofillers via hand layup fabrication. Mechanical and thermogravimetric analyses assessed composites with varying WC content (0-3 wt.%). Results showed deteriorating effect on tensile strength, while flexural strength, interlaminar shear, and impact resistance improved significantly at low nanofiller loadings (<= 0.4 wt.%). Beyond this threshold, agglomeration is due to high surface energy limited gains. The specimens with nanofillers showed a notable improvement in wear resistance when compared to unfilled composites, although thermal stability was largely unaffected. SEM micrographs corroborated mechanical trends, confirming optimal dispersion at lower concentrations. These findings highlight WC's potential to selectively enhance basalt fiber-reinforced polymer composites performance within strict compositional limits. (sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)/(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic). (sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (BFRP)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (WC)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)BFRP(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)WC(sic)(sic) (0-3 wt.%)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic) (<= 0.4 wt.%)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).SEM(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic),(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).(sic)(sic)(sic)(sic)(sic)(sic)(sic)WC(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic)(sic).

In recent years, natural fiber reinforced composites have gained considerable attention of industries and researchers due to their sustainability, lightweight and cost-effectiveness. This study explores the mechanical and thermal performance of cotton/bamboo/glass (C/B/G) fiber-reinforced hybrid epoxy composites fabricated via hand lay-up and compression molding with a focus on how fiber pre-treatment and chemical bonding mechanisms impact their properties. From the test results of carbon/glass (C/G), bamboo/glass (B/G) and cotton/bamboo/glass (C/B/G) fiber reinforced composites, it is observed that the C/B/G hybrid composite demonstrated superior results. This laminate attained a tensile strength of 121.82 MPa, which is 12.72