Journal of Fibers and Polymer Composites

Additive Manufacturing of Fiber-Reinforced Polymers: A Route to Sustainable and Advanced Manufacturing

Madhu Puttegowda, Sanjay Mavinkere Rangappa, Suchart Siengchin — Mon, 30 Mar 2026 00:00:00 +0700

Editor's Corner

Tensile Strength of Adhesively Bonded Steel to Hybrid Sisal-Glass Reinforced HDPE Composite Joint for Automobile Side Body Panel Application

Sun, 15 Feb 2026 00:00:00 +0700

The increasing demand for lightweight, high-performance, and environmentally sustainable materials in the automotive industry has accelerated the adoption of adhesive bonding as an alternative to conventional joining techniques such as welding and mechanical fastening. Reliable prediction of stress distribution and debonding behavior in adhesively bonded composite–metal joints is therefore essential to ensure structural integrity under service loading. This study presents a comprehensive computational and experimental investigation of the tensile stress behavior of adhesively bonded single-side strap joints (ABSSSJ) formed between steel and hybrid sisal–glass reinforced high-density polyethylene (HDPE) composites for automobile side body panel applications. The hybrid composite adherend was modeled as an orthotropic laminate with a ([0°/+45°/90°/–45°/0°]) stacking sequence, while the adhesive layer was characterized using different epoxy systems (Araldite 2020, Araldite 2015, and AV138) with thicknesses ranging from 0.12 to 1.0 mm and elastic moduli between 1.85 and 6 GPa. An analytical variational method was employed to evaluate shear and peel stress distributions, and the results were verified using a cohesive zone model (CZM)-based finite element approach to simulate crack initiation and progressive debonding. Experimental tensile and shear tests were conducted to validate the numerical predictions. The results indicate that an adhesive thickness of approximately 0.75 mm provides an optimal balance between load transfer efficiency and stress reduction at the overlap edges. The numerical and analytical predictions exhibited strong agreement with experimental measurements, with a maximum deviation below 6%. The validated results demonstrate that hybrid sisal–glass reinforced HDPE composites, when combined with appropriate adhesive and joint design, offer a promising, lightweight, and sustainable solution for automotive side body panel structures.

Modified PVA Film from Methanol-Soluble Phenolic Extracts of Spatholobus littoralis Hask as Active Pharmaceutical Packaging

Fri, 20 Feb 2026 00:00:00 +0700

The development of active pharmaceutical packaging based on biodegradable materials is an important strategy to reduce dependence on single-use plastics and their environmental impact. Polyvinyl alcohol (PVA) is a potential biodegradable polymer, but it has limitations in terms of exposure to ultraviolet (UV) radiation and microbial contamination. This study aims to develop a modified PVA film with methanol-soluble phenolic extract of Spatholobus littoralis Hask as active pharmaceutical packaging with UV protection, antioxidant, and antibacterial functions. The phenolic extract was obtained through a maceration method using methanol as a solvent, while the PVA film was fabricated using the solution casting technique. The PVA film was modified with varying concentrations of phenolic extract of 0, 1.25, 2.5, and 5wt% (PPE0, PPE1.25, PPE2.5, and PPE5), then evaluated for its UV protection properties, antioxidant activity, and antibacterial activity. The results showed that the addition of S. littoralis phenolic extract was able to increase the ability of PVA films to block UV radiation completely (100%) in the 200–400 nm wavelength range. Antioxidant activity testing using the DPPH method showed an increase in free radical scavenging ability as the concentration of phenolic extract increased. In addition, the modified PVA film showed significant antibacterial activity against Staphylococcus aureus and Escherichia coli. These findings indicate that S. littoralis Hask phenolic extract has potential as a natural bioactive agent in the development of environmentally friendly and multifunctional active pharmaceutical packaging, with dual protection capabilities against UV degradation and microbial contamination. This research makes an important contribution to the development of sustainable pharmaceutical packaging materials based on renewable natural resources.

Structural Characterization and Tensile Properties of Untreated and Alkali Treated Water Hyacinth Fibre

Augustine Uchechukwu Elinwa, Awari Amma Ishaya — Fri, 27 Feb 2026 00:00:00 +0700

Water hyacinth (Eichhornia crassipes) is an abundant aquatic biomass whose utilisation as a reinforcement fibre is limited by high contents of hemicellulose, lignin, waxes, and inorganic deposits. This study evaluates the effect of 10 % NaOH treatment on the structural, chemical, thermal, and mechanical properties of water hyacinth fibres (WHF). Scanning electron microscopy with energy-dispersive spectroscopy (SEM/EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), X-ray fluorescence (XRF), thermogravimetric analysis (TGA/DTG), and single-fibre tensile testing were employed. Alkali treatment induced extensive defibrillation of compact fibre bundles into individual microfibrils (≈2–7 µm), transformation of cellulose I to cellulose II, and a marked increase in crystallinity from approximately 25 % to 71 %. Potassium and chloride contents were reduced by more than 99 %, and the maximum thermal degradation temperature increased from about 337 °C to 367 °C. Tensile strength and Young’s modulus increased from 18.4 ± 3.1 MPa to 58.1 ± 2.9 MPa and from 1.42 ± 0.18 GPa to 4.83 ± 0.23 GPa, respectively. These results demonstrate that NaOH treatment effectively purifies and structurally optimises WHF, significantly enhancing its thermal resistance and mechanical performance for sustainable composite reinforcement applications.

Characteristics of bio-composites from Polyvinyl alcohol reinforced micro-cellulose fibers of Paederia foetida

Sun, 08 Mar 2026 00:00:00 +0700

The use of renewable natural fibers as reinforcements in biodegradable matrices has been boosted by the development of sustainable polymer materials. The purpose of this work is to examine the properties of bio-composites made of polyvinyl alcohol (PVA) reinforced with micro-cellulose fibers that are isolated from the underused plant resource Paederia foetida (MSPf). After retting and alkaline and bleaching treatments, micro-cellulose was obtained and added to PVA at a weight percentage of 5% utilizing the solution casting technique. The biocomposites' mechanical, thermal, water absorption, and morphological characteristics were assessed. When MSPf was added, PVA's tensile strength rose from 20.69 MPa to 23.10 MPa, and its elastic modulus increased dramatically, suggesting better stiffness and efficient stress transfer. The improvement is ascribed to the hydroxyl groups of PVA and cellulose having strong hydrogen bonds and good interfacial adhesion. Due to limited polymer chain mobility, elongation at break decreased, but the composite showed better structural integrity. After 36 h, water absorption attained an equilibrium value of 1.461%, indicating the creation of a compact fiber-matrix network. When compared to clean PVA, thermogravimetric analysis showed better thermal stability, and SEM verified strong interfacial compatibility and homogeneous dispersion. These results show that micro-cellulose derived from Paederia foetida is a viable sustainable reinforcement that can improve the performance of bio-composites based on PVA.

Effect of Different Drying Temperatures on the Physicochemical Properties of Sago Starch-Bacterial Cellulose Film Incorporated with Gunuang Omeh Orange Essential Oil

Maulana Yuda Anantama, Fadli Hafizulhaq, Andasuryani Andasuryani — Wed, 11 Mar 2026 00:00:00 +0700

Extensive and irresponsible use of conventional plastic has brought serious problems to the planet due to its low biodegradability. In order to reduce the risks, packaging materials made from biodegradable materials are extremely needed. This study develops active packaging films using sago starch and bacterial cellulose incorporated with Gunuang Omeh orange peel essential oil. It also evaluated the effect of different drying temperatures on the physicochemical, mechanical, structural, and antimicrobial properties of the resulting films. The solvent casting method was used to prepare sample films with 3 drying temperatures (40, 45, and 50°C). The functional properties and antibacterial activity against E. coli and S. aureus of films with and without essential oil were characterized and analyzed. The results showed that drying temperature significantly influences the performance of the biofilms. Higher tensile strength (2.38 MPa) and lower moisture absorption were found at 45°C dried films. The presence of essential oil slightly increased water solubility and improved antibacterial activity, with inhibition zones ranging from 7.70–15.77 mm against E. coli and 4.83–5.75 mm against S. aureus. In conclusion, sago starch–bacterial cellulose films incorporated with Gunuang Omeh orange essential oil demonstrate a future potential as eco-friendly packaging materials, with drying temperature identified as a critical processing parameter for optimizing functional performance.

The Effect of Temperature on Manufacturing Process of Tannin Acid-Based Adhesive Materials on Mechanical and Physical Properties

Sun, 15 Mar 2026 00:00:00 +0700

This study focuses on the development and characterization of adhesives based on Polyvinyl Alcohol (PVA), Tannic Acid (TA), and Cellulose Nanofibre (CNF). The main objective is to optimize the temperature used in the production process. Phenol-formaldehyde and other synthetic adhesives frequently encounter environmental obstacles, necessitating the search for more ecologically sound alternatives. TA, a naturally occurring polyphenolic molecule, has significant potential as an eco-friendly glue ingredient. This study assesses the impact of temperature fluctuations (30, 45, 60, 75, and 90°C) during the glue manufacturing process on its mechanical characteristics, specifically emphasizing shear stress. Experiments were conducted at a rotational speed of 1500 revolutions per minute (RPM) for 30 minutes. The results indicated that the adhesive performed best at 90°C, achieving a maximum shear stress value of 3.41 MPa. The results demonstrated a significant enhancement in the shear strength of the bioadhesive, exhibiting an approximately sixfold increase as the processing temperature was elevated from 30°C to 90°C. Microstructural analysis reveals that the voids formed during the mixing process decrease at this specific temperature. The results indicate that elevated temperatures lead to a significant reduction in void formation. The FTIR measurement revealed the absorption of hydroxyl groups around 3305 cm⁻¹, suggesting the presence of robust crosslinking. Furthermore, elevated temperatures lead to a significant reduction of free OH- groups within the bioadhesive. The PVA/TA/CNF adhesive possesses extensive potential for application in industries that necessitate adhesives with exceptional strength. The study is anticipated to offer comprehensive understanding of how to improve the manufacturing process of TA-based adhesives, and its impact on the creation of adhesive materials that are more sustainable and environmentally friendly.

Bacterial Consortia as a Sustainable Alternative to Jute Batching Oil (JBO) in Jute Yarn Manufacturing Process

Sun, 29 Mar 2026 00:00:00 +0700

Jute fiber used in the production of yarn is traditionally treated with a 2% emulsion of jute batching oil (JBO) to reduce stiffness and improve processability. However, due to the high cost and potential carcinogenic effects of JBO, there is a pressing need for alternative methods. This study investigates the use of a microbial consortium to achieve a cost-effective and eco-friendly reduction of JBO use in yarn production. A total of 51 bacterial strains were isolated from JBO-treated jute fiber at Janata Jute Mills, with 17 strains exhibiting significant growth in 2% JBO. After excluding duplicates, potential pathogens, and strains with endoglucanase activity, a final consortium of nine bacteria was established. The physical properties of jute fiber treated with this consortium alongside varying concentrations of JBO (1% and 2%) were analyzed over different incubation periods. Results indicated that treatment with 1% JBO and the bacterial consortium produced comparable effects on temperature and moisture regain to the control group (2% JBO). Notably, fibers treated with the consortium exhibited enhanced elasticity, showing a 46.6% increase in maximum pressure and 12.2% increase in extension at breakage compared to the control (2% JBO). Additionally, wastage during processing was reduced by 24.1% for breaker card processing in the treated group. Scanning electron microscopy (SEM) revealed a rough surface morphology in the treated fibers, indicative of biofilm formation. This study suggests that employing microbial consortia with reduced JBO concentrations offers a promising alternative for enhancing fiber quality in jute yarn manufacturing while promoting environmentally sustainable practices.

Effect of Hair Particle Filler on the Characteristics of Green Composite Based on Bacterial Cellulose

Umi Lailatul Jamilah, Endhah Purwandari, Sujito Sujito — Sun, 29 Mar 2026 00:00:00 +0700

The growing demand for sustainable materials and effective waste management has encouraged the development of environmentally friendly composites. Green composites are a promising alternative to conventional materials for environmental preservation. In this study, bacterial cellulose derived from nata de coco was used as a matrix, while haircut waste particles served as a filler. Composites were fabricated via compression molding at 170 °C with filler contents of 0, 15, 25, 35, and 45 wt.%. The synthesized materials were characterized through tensile testing, scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. Increasing hair-particle content increased the elastic modulus from 44.11 ± 3.02 MPa (A1) to 130.46 ± 4.94 MPa (A2), indicating enhanced stiffness of the composite; however, further increases in filler content slightly reduced the modulus due to possible void formation and weaker interfacial adhesion. In contrast, the tensile strength decreased progressively from 11.54 ± 0.56 MPa (A1) to 5.16 ± 0.52 MPa (A5) with increasing filler content. SEM observations revealed the formation of voids and weaker matrix–filler interactions at higher filler contents, which contributed to the reduction in tensile strength. FTIR spectra showed the presence of O–H, C–H, and C=O functional groups, suggesting possible interactions between bacterial cellulose and hair particles. Overall, a filler content of 15 wt.% provides the best balance between stiffness and structural integrity, demonstrating the potential of hair waste as a sustainable reinforcement in bacterial cellulose-based green composites.