Search Results (146)

Three-dimensional printed polycaprolactone (PCL) tissue engineering scaffolds have drawn increasing interest from the medical industry due to their excellent biocompatibility and biodegradability, yet PCL’s poor mechanical performance has limited their applications. This study introduces a biocompatible and biodegradable polylactic acid (PLA) fiber reinforced PCL (PLA/PCL) composite as the filament for 3D printed scaffolds to significantly enhance their mechanical performance: Special-made PLA short fiber mat was infused with PCL matrix and rolled into PLA/PCL filaments through a “Vacuum Assisted Resin Infusion” (VARI) process. The investigation revealed that the PLA fibers are highly oriented along the printing direction when using this filament for 3D printing due to the unique microstructure formed during the VARI process. At the same PLA fiber content, the percentage increase in Young’s modulus of the 3D printed strands using the filaments produced by the VARI process is 127.6% higher than the 3D printed strands using the filaments produced by the conventional melt blending process. The 3D printed tissue engineering scaffolds using the PLA/PCL composite filament with 11 wt% PLA fiber content also achieved an exceptional 84.2% and 143.3% increase in peak load and stiffness compared to the neat PCL counterpart. Full article

We report an investigation on the cobalt(II) chelation mechanism by a modified α-maltoside ligand 9 decorated with two iminodiacetate (IDA) residues on C6,C6′ positions. Herein we uncovered the capacity of this biodegradable ligand to chelate cobalt(II), an ionic metal contaminant in the environment that is used, in particular, in lithium-ion batteries. The interactions between cobalt(II) and synthesized ligand 9 were systematically studied using different analytical methods such as ¹H and ¹³C NMR, potentiometry, spectrophotometry, ITC, and ICP-AES. We observed a high affinity for the 1:1 complex, one cobalt(II) associated with two iminodiacetate groups, which is 10-fold higher than the 2:1 complex, where each of the two IDA groups interacts alone with a cobalt(II). Taking into account the log β_CoL value obtained (≈12.3) with the stoichiometry 1:1, the strength of this complexation with cobalt(II) can be ranked as follows for the most common ligands: IDA < MIDA < NTA < 9 < EDTA < TTHA < DTPA. We further completed a preliminary remediation test with water contaminated with cobalt(II) and recovered cobalt(II) metal using Chelex^® resin, which allowed a recycling of the synthetic ligand for future recovering experiments. The results shed light on the great potential of using this synthetic ligand as an effective and green remediation tool. Full article

As a large class of natural organic compounds, vegetable oil is generally composed of 95% fatty acid triglycerides and very few complex non-triglycerides. It has many advantages, such as sufficient yield, low price, distinct structural characteristics, and biodegradability. UV curing technology is known as a new method for the green industry in the 21st century due to its high efficiency, economy, energy conservation, high adaptability, and environmental friendliness. Therefore, UV-curable resins based on UV-curing technology has attracted widespread attention, converting epoxy soybean oil, castor oil, tung oil and other vegetable oils into high-performance plant oil-based UV-curable resins with higher molecular weight, multi-rigid ring and high reactivity, and the curing performance has been greatly improved, and the technology has been widely used in the field of polymer materials such as coatings, inks and adhesives. In this article, the recent research progress on this topic was summarized, and emphasis was put on the research on the resins from soybean oil and castor oil. Full article

Human development has led to increased production of oil and gas, mainly as energy sources, which, however, are responsible for contamination and metal corrosion in industrial, marine, and terrestrial environments. Lubricating oil, in particular, is widely used in generators and industrial machines in the electric sector and is responsible for contamination not only in industrial environments but also in many terrestrial and aquatic ecosystems. In this context, this study aimed to apply the Starmerella bombicola ATCC 222214 biosurfactant to inhibit metal corrosion in seawater and in an Accelerated Corrosion Chamber (ACC). For this purpose, its toxicity against the microcrustacean Artemia salina, its dispersion capacity, and its ability to promote oil biodegradation in a saline environment were investigated. The biosurfactant, when applied at twice its Critical Micellar Concentration (CMC), caused low mortality (30.0%) of microcrustaceans in a saline environment, and, in its crude form, the biosurfactant ensured the dispersion of no less than 77.56% of residual engine oil in seawater. Oil biodegradation by autochthonous microorganisms reached 94.39% in the presence of the biosurfactant in seawater. Furthermore, the biosurfactant, when used at twice its CMC, acted satisfactorily as a corrosion inhibitor by reducing the mass loss of galvanized iron specimens (plates) in seawater in a static system to only 0.36%. On the other hand, when the biosurfactant was added at the CMC as an atmospheric corrosion inhibitor, the reduction in mass loss of carbon steel plates treated in the ACC was 17.38% compared to the control containing only a biodegradable matrix based on vegetable resin. When the biosurfactant was incorporated into different paints applied to galvanized iron plates placed in contact with the salt spray produced in the ACC, the best result was obtained using the biomolecule at a concentration of 3% in the satin paint, ensuring a plate mass loss (29.236 g/m²) that was almost half that obtained without surfactant (52.967 g/m²). The study indicated the use of yeast biosurfactant as a sustainable alternative in combating the contamination of marine environments and metal corrosion, with the aim of preserving the environment and improving the quality of life in aquatic and terrestrial ecosystems. Full article

Olive mill wastewater (OMWW) has high energetic potential due to its organic load, but its complex composition and toxicity limit efficient energy recovery. This study proposes an innovative integrated process combining continuous resin adsorption with anaerobic digestion to detoxify OMWW and recover renewable energy simultaneously. It studies the recovery of polyphenols, methane production, and substrate degradation efficiency using resin column bed heights (C1: 5.7 cm, C2: 12.1 cm, C3: 18.5 cm), as well as kinetic modeling of organic matter degradation. Adsorption reduced chemical oxygen demand (COD) by up to 80% and polyphenols by up to 64%, which significantly improved substrate biodegradability from 34% to 82%, corresponding to a methane yield of 287 mL CH₄/g COD. Organic matter was fractioned into rapid (S₁), moderate (S₂), and slow (S₃) biodegradable fractions. The highest degradation kinetics was C3, with methane production rates of K₁ = 23.86, K₂ = 2.47, and K₃ = 2.92 mL CH₄/d. However, this condition produced the lowest volumetric methane production due to excessive COD removal, including readily biodegradable matter. These results highlight the importance of optimizing the adsorption step in order to find to a balance between detoxification and energy recovery from OMWW, thus supporting the principles of circular economy and promoting renewable energy production. Full article

Natural fibre-reinforced composites are becoming increasingly popular due to their affordability, sustainability, and biodegradability. These composites, made from recyclable materials, are suitable for various sustainable energy applications due to their remarkable mechanical properties and life cycle advantages. The biodegradable composite materials are a sustainable alternative for energy applications. This composite construction uses Soric XF (Lantor Composites, Veenendaal, The Netherlands) as the fibre reinforcement core material and jute fibre, an eco-friendly and sustainable substitute for glass fibre reinforcement composite materials, as the outer face sheet obtained from jute bags. The dry fibres are piled as dry loads at various fibre orientation angles, including 0°, 45°, and 90°, and this orientation will be reflected in the composite strength. Vacuum-assisted resin transfer moulding (VARTM) is a technique used to fabricate this material at room temperature. Further, this research focuses on a comparative analysis of experimental and computational results involving composite materials with jute fibre as the outer face sheet and Soric XF as the fibre reinforcement core material. The experimental investigation included tensile ASTM D638-03 and flexural ASTM D790 to evaluate the composite’s mechanical properties and structural integrity under various load conditions. Simultaneously the computational simulations were performed using the ANSYS-Mechanical 2023 R2 to replicate these conditions and predict the composite’s performance. The experimental and simulated data were analysed and compared. This study demonstrates the efficacy of using computational tools to predict the behaviour of natural fibre composites. It underscores the importance of experimental validation for enhancing the reliability of simulation models. The results from the computational study are compared with the experimental results to study the predictive nature of the NFRC material. Full article

Antistatic and anti-flame biodegradable polymer composites were developed by melt-blending polybutylene succinate (PBS) with epoxy resin, polybutylene adipate-co-terephthalate (PBAT), and MgO particles. The composite films were prepared using a two-roll mill and an extrusion-blown film machine. Plasma and sparking techniques were used to improve the antistatic properties of the composites. The PBS/E1/PBAT/MgO 15% composite exhibited an improvement in V-1 rating of flame retardancy, indicating an enhancement in the flame retardancy of biodegradable composite films. The tensile strength of the PBS/PBAT blend increased from 19 MPa to 25 MPa with the addition of 1% epoxy due to the epoxy reaction increasing compatibility between PBS and PBAT. The PBS/E1/PBAT and PBS/E1/PBAT blends with MgO 0, 0.5, and 1% showed increases in the contact angle to 80.9°, 83.0°, and 85.7°, respectively, because the epoxy improved the reaction between PBS and PBAT via the MgO catalyst effect. Fourier-transform infrared spectroscopy confirmed the reaction between the epoxy groups of the epoxy resin and the carboxyl end groups of PBS and PBAT by new peaks at 1246 and 1249 cm⁻¹. Plasma technology (sputtering) presents better antistatic properties than the sparking process because of the high consistency of the metal nanoparticles on the surface. This composite can be applied for electronic devices as sustainable packaging. Full article

Lignin, an abundant and renewable biopolymer, has gained significant attention as a sustainable modifier and building block in polymeric materials. Recent advancements highlight its potential to tailor mechanical, thermal, and barrier properties of polymers while offering a greener alternative to petroleum-based additives. This review provides an updated perspective on the incorporation of lignin into various polymer matrices, focusing on lignin modification techniques, structure–property relationships, and emerging applications. Special emphasis is given to recent innovations in lignin functionalization and its role in developing high-performance, biodegradable, and recyclable materials such as polyurethanes, epoxy resins, phenol-formaldehyde resins, lignin-modified composites, and lignin-based films, coatings, elastomers, and adhesives. These lignin-based materials are gaining attention for potential applications in construction, automated industries, packaging, textiles, wastewater treatment, footwear, supporting goods, automobiles, printing rollers, sealants, and binders. Full article

The use of natural fibers in hydro turbine rotors promotes sustainability by offering biodegradable, renewable materials with a lower carbon footprint. This study compares the hydrodynamic performance of two rotors in a gravitational vortex turbine: Rotor 1, 3D-printed with polylactic acid (PLA), and Rotor 2, made from fique fiber and epoxy resin using manual molding. To compare the rotors, experimental tests were conducted on a laboratory-scale setup, where the behavior of both rotors was evaluated under different flow regimes. Rotor 1 achieved 61.01% efficiency at an angular velocity ($\omega$) 160 RPM, while Rotor 2 reached only 19.03% at $\omega$ of 165 RPM. The lower performance of Rotor 2 was due to dynamic imbalances and mechanical vibrations, leading to energy losses. These challenges highlight the limitations of manual molding in achieving precise rotor geometry and balance. To improve natural fiber rotor viability, optimizing manufacturing techniques is crucial to enhance dynamic balance and minimize vibrations. Advancements in fabrication could bridge the performance gap between natural and synthetic materials, making bio-based rotors more competitive. This study emphasizes the potential of natural fibers in sustainable energy and the need to refine production methods to maximize efficiency and reliability. Addressing these challenges will help integrate eco-friendly rotors into hydro turbine technologies. Full article

To address the problem of environmental pollution caused by the extensive use of low-density polyethylene (LDPE) mulch film, this study developed a novel sprayable mulch using natural fibers and biodegradable polymers. Urea–formaldehyde resin (UF), strengthened with polyvinyl alcohol (PVA), was used as a modifier to induce beneficial physicochemical structural changes in PVA-modified urea–formaldehyde (PUF) resins. Characterization of these resins was conducted using Fourier transformation infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM). Preparation of the biodegradable mulch was conducted using Xuan paper waste residue (XP) as an enhancer, with PUF as the auxiliary agent. The resulting film (PUF-XP) was examined for differences in thickness, morphological characterization, and rate of weight loss, and the effects of different covering films on cucumber growth, root development, soil temperature, and weed control were evaluated. Characterization reveals that when the PVA content was 4% (W4UF), the film had the lowest free formaldehyde content (0.26%) and highest elongation at break (5.70%). In addition, W4UF could easily undergo thermal degradation at 278.4 °C and possessed a close-knit, three-dimensional structural network. W4UF was then mixed with paper powder and water in various proportions to produce three mulch films (BioT1, BioT2, and BioT3) that demonstrated excellent water retention and heat preservation and inhibited weed growth by 68.8–96.8%. Compared to no mulching (NM), BioT1 increased both the specific root length and root density, as well as improved the plant height, stem diameter, and total biomass of the cucumbers by 43.5%, 34.1%, and 33.9%, respectively. Therefore, a mass ratio of paper powder, water, and W4UF of 1:30:2 produced a biodegradable mulch film that could be used as an alternative to LDPE, mitigating the environmental pollution rendered by synthetic plastic mulch films and offering the potential for a sustainable agricultural application. Full article

The issue of energy transfer is extremely important. In order to achieve the lowest possible energy consumption and the required thermal efficiency in energy-efficient buildings, it is necessary, among other things, to minimize the heat-transfer coefficient, which depends on the properties of the insulating material. Analyses of the relationship between the structure of a material and its thermal conductivity coefficient have shown that lower values of this coefficient can be achieved with a more complex structure that mimics natural forms. This paper presents a design method based on the Voronoi diagram to obtain a three-dimensional structure of a porous composite material. The method was found to be effective in producing structures with predefined and functionally graded porosity. The porous specimens were fabricated from a biodegradable soybean oil-based resin using mSLA additive technology. Analyses were performed to determine the thermal parameters of the anisotropic composites. Experimental results showed that both porosity and irregularity affect the thermal properties. The lowest thermal conductivity coefficients were obtained for a 100 mm-thick prototype composite with the following parameters: wall thickness D = 0.2 mm, cell size S = 4 mm, number of structural layers n = 2, and degree of irregularity R = 4. The lowest possible thermal conductivity of the insulation was 0.026 W/(m·K), and the highest possible thermal resistance was 3.92 (m²·K)/W. The method presented in this study provides an effective solution for nature-inspired design and topological optimization of porous structures. Full article

Bisphenol A (BPA) is an industrial chemical used primarily in the manufacture of polycarbonate plastics and epoxy resins. BPA is considered an endocrine-disrupting chemical (EDC) because it interferes with hormonal systems. Over the decades, several techniques have been proposed for BPA removal in wastewaters. This study discusses recent advancements and progress of effective techniques for BPA removal, including membrane, adsorption, advanced oxidation process (AOPs), and biodegradation. The mechanisms of BPA adsorption on modified adsorbents include pore-filling, hydrophobic interactions, hydrogen bonding, and electrostatic interactions. Among the various agricultural waste adsorbents, Argan nut shell-microporous carbon (ANS@H20–120) exhibited the highest efficiency in removing BPA. Furthermore, the performance of magnetic treatment for activated carbon (AC) regeneration is introduced. According to the present study, researchers should prioritize agricultural waste-based adsorbents such as ACs, highly microporous carbons, nanoparticles, and polymers for the removal of BPA. In particular, the combination of adsorption and AOPs (advanced oxidations) is regarded as an efficient method for BPA removal. A series of relevant studies should be conducted at laboratory, pilot, and industrial scales for optimizing the application of agricultural waste-based AC to reduce BPA or other refractory pollutants from an aqueous environment. Full article

Nitrophenols are persistent organic pollutants that pose serious environmental and health risks due to their toxic and lipophilic nature. Their persistence arises from strong aromatic stability and resistance to biodegradation, while their lipophilicity facilitates bioaccumulation, exacerbating ecological and human health concerns. To address this challenge, this study focuses on the synthesis and characterization of two different types of hybrid multi-core magnetic catalysts: (i) cobalt ferrite (Co-Fe₂O₄), which exhibits ferrimagnetic properties, and (ii) magnetite (Fe₃O₄), which demonstrates close superparamagnetic behavior and is coated with a novel and less hazardous phloroglucinol–glyoxal-derived resin. This approach aims to enhance catalytic efficiency while reducing the environmental impact, offering a sustainable solution for the degradation of nitrophenols in aqueous matrices. Transmission electron microscopy (TEM) images revealed the formation of a multi-core shell structure, with carbon layer sizes of 6.6 ± 0.7 nm for cobalt ferrite and 4.2 ± 0.2 nm for magnetite. The catalysts were designed to enhance the stability and performance in catalytic wet peroxide oxidation (CWPO) processes using sol–gel and solution combustion synthesis methods, respectively. In experiments of single-component degradation, the carbon-coated cobalt ferrite (CoFe@C) catalyst achieved 90% removal of 2-nitrophenol (2-NP) and 96% of 4-nitrophenol (4-NP), while carbon-coated magnetite (Fe₃O₄@C) demonstrated similar efficiency, with 86% removal of 2-NP and 94% of 4-NP. In the multi-component system, CoFe@C exhibited the highest catalytic activity, reaching 96% removal of 2-NP, 99% of 4-NP, and 91% decomposition of H₂O₂. No leaching of iron was detected in the coated catalysts, whereas the uncoated materials exhibited similar and significant leaching (CoFe: 5.66 mg/L, Fe₃O₄: 12 mg/L) in the single- and multi-component system. This study underscores the potential of hybrid magnetic catalysts for sustainable environmental remediation, demonstrating a dual-function mechanism that enhances catalytic activity and structural stability. Full article

The increasing environmental issue related to textile waste, especially synthetic fibers treated with acrylic resins, demands the creation of sustainable recycling techniques. Biotechnological methods, such as microbial degradation, present a viable solution for the elimination of these coatings and the recovery of important fibers. This study investigates the potential of a biotechnological approach for the removal of acrylic resins from coated woven textile wastes. The biodegradation process of coated woven fabric after the pretreatment at a high temperature (121 °C) or 6% H₂O₂ was performed using the hydrocarbon-degrading bacterial strain Gordonia alkanivorans S7. Over a 72 h biodegradation period, an increase in emulsifying and esterase activities was observed. A reduction mass of the coated textile waste by up to 7 wt% was achieved, and the elimination of acrylic resin was confirmed through FTIR analysis. The findings indicate the usefulness of the biotechnological method in eliminating acrylic resin from textile waste, presenting a viable strategy for polyester fiber recovery and substantially mitigating its environmental impact. Full article

This paper review deals with frequent technologies of the production of materials based on Wood Plastic Composite, their brief definition, and description of components. The choice of processing technology depends on the polymer applied and the shape required of the part or the component. In the case of thermoplastic matrices, the dominant are extrusion and injection molding. In the case of thermosets application, the following technologies can be used: Resin Transfer Molding and Sheet Molding Compound. Currently, the research is also widely focused on composites with a matrix made of biodegradable thermoplastics—polylactide, which also brings to the forefront 3D printing technology of Fused Deposition Modeling. Each of these technologies is—to a certain extent—limited and impacts on the final characteristics of the composite material and its use. Full article