Composite Biomaterials Research Articles

Trends and Considerations in Annulus Fibrosus In Vitro Model Design.

Annulus Fibrosus (AF) tissue integrity maintains intervertebral disc (IVD) structure, essential to spine mobility and shock absorption. However, this tissue, which confines nucleus pulposus (NP), has been poorly investigated, partially due to the lack of appropriate study models. This review provides a comprehensive analysis of AF in vitro models. By critically assessing the current AF in vitro models, this works thoroughly identifies key gaps in replicating the tissue's complex microenvironment. Finally, we outline the essential criteria for developing more accurate and reliable AF models, emphasizing the importance of biomaterial composition, architecture, and microenvironmental cues. By advancing in vitro models, we aim to deepen the understanding of AF failure mechanisms and support the development of novel therapeutic strategies for IVD herniation. Insights gained from this review may also have broader applications in regenerative medicine, particularly in the study and treatment of other connective tissue disorders. STATEMENT OF SIGNIFICANCE: This review evaluates the current in vitro models of the annulus fibrosus (AF), a key component of the intervertebral disc (IVD). By identifying gaps in these models, particularly in replicating tissue's complex microenvironment, we propose essential criteria for the development of more accurate AF models, to better understand the pathomechanisms and potentially aid the development of therapeutic approaches for spinal disorders. The findings also extend to broader studies of musculoskeletal tissue disorders in the context of regenerative medicine, appealing to a diverse biomedical research readership.

A New Means to Generate Liposomes by Rehydrating Engineered Lipid Nanoconstructs

The concept and feasibility of producing liposomes by rehydrating engineered lipid nanoconstructs are demonstrated in this study. Nanoconstructs of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) were produced using a microfluidic delivery probe integrated with an atomic force microscope. The subsequent rehydration of these POPC constructs led to the formation of liposomes, most of which remained adhered to the surface. The size (e.g., diameter) of the liposomes could be tuned by varying the lateral dimension of the lipid constructs. Hierarchical liposomal structures, such as pentagons containing five liposomes at the corners, could also be designed and produced by depositing lipid constructs to designated locations on the surfaces, followed by rehydration. This new means allows for regulating liposomal sizes, distributions, and compositions. The outcomes benefit applications of liposomes as delivery vehicles, sensors, and building blocks in biomaterials design. The ability to produce hierarchical liposomal structures benefits numerous applications such as proto-cell development, multiplexed bio-composite materials, and the engineering of local bio-environments.

Advancements in Silkworm-Derived Silk Fibroin Biomaterials for Peripheral Nerve Regeneration

Regenerating injured nerves is difficult because they have little spontaneous regeneration potential. Advances in tissue engineering and regenerative medicine have emphasized the possibility of biomaterial-based methods for nerve healing. Natural protein-based biomaterials have benefits over synthetic ones, such as biocompatibility, non-immunogenicity, and biodegradability. Silk fibroin, generated from mulberry and non-mulberry silkworms, is especially promising because of its abundance, simplicity of processing into nerve-like structures, adjustable biodegradability, and mechanical robustness. Furthermore, non-mulberry silk fibroin contains the cell-affinitive RGD tripeptide, which enhances its ability to repair nerves. Studies using silk fibroin (SF)--based nerve conduits have demonstrated nerve regeneration rates of up to 80–90% compared to autografts, which remain the clinical gold standard. SF conduits exhibit outstanding mechanical properties, with tensile strengths up to 300 MPa and elastic moduli adjustable between kPa-MPa range, which closely mimic the native tissue and ensure durability in dynamic environments. This review explores the diverse types of silkworm silk fibroin (SSF) and their applications in biomaterial-based Peripheral Nerve Repair (PNR). It discusses the integration of SSF with other biopolymers and synthetic polymers, highlighting advancements in nerve guidance channels incorporating electro-conductive materials to enhance regeneration rates. The literature search was primarily conducted using the Web of Science database, employing relevant keyword combinations such as “silk fibroin + nerve repair,” “silk fibroin + peripheral nerve repair,” “silk + nerve repair,” and “silk + nerve repair + electrical stimulation.” As this review focuses on silkworm silk-based biomaterials, studies involving spider silk or recombinant silk-based biomaterials were excluded. The period considered began with the earliest relevant studies, with an emphasis on more recent advancements up to November 2024 to capture the latest developments in the field. Identified studies were categorized based on the biomaterial composition, including pure silk biomaterials, silk biopolymer binary composites, silk synthetic binary composites, and silk-hybrid composites. Key findings were synthesized to highlight the progress, challenges, and future directions in applying silk fibroin-based scaffolds and electrical stimulation technologies for nerve repair. The findings provide insights into the potential of SSF-based biomaterials and propose future directions for developing advanced nerve repair strategies.

Zero Waste Concept in Production of PLA Biocomposites Reinforced with Fibers Derived from Wild Plant (Spartium junceum L.) and Energy Crop (Sida hermaphrodita (L.) Rusby).

This research follows the principles of circular economy through the zero waste concept and cascade approach performed in two steps. Our paper focuses on the first step and explores the characteristics of developed biocomposite materials made from a biodegradable poly(lactic acid) polymer (PLA) reinforced with natural fibers isolated from the second generation of biomass (agricultural biomass and weeds). Two plants, Spartium junceum L. (SJL) and Sida hermaphrodita (SH), were applied. To enhance their mechanical, thermal, and antimicrobial properties, their modification was performed with environmentally friendly additives-linseed oil (LO), organo-modified montmorillonite nanoclay (MMT), milled cork (MC), and zinc oxide (ZnO). The results revealed that SH fibers exhibited 38.92% higher tensile strength than SJL fibers. Composites reinforced with SH fibers modified only with LO displayed a 27.33% increase in tensile strength compared to neat PLA. The addition of LO improved the thermal stability of both biocomposites by approximately 5-7 °C. Furthermore, the inclusion of MMT filler significantly reduced the flammability, lowering the heat release rate to 30.25%, and enabling the categorization of developed biocomposite in a group of flame retardants. In the second step, all waste streams generated during the fibers extraction process are repurposed into the production of solid biofuels (pellets, briquettes) or biogas (bio)methane.

Investigation of Biodegradation, Artificial Aging and Antibacterial Properties of Poly(Butylene Succinate) Biocomposites with Onion Peels and Wheat Bran.

The present article focuses on the characterization of the new biocomposites of poly(butylene succinate) (PBS) with fillers of plant origin such as onion peels (OP) and durum wheat bran WB (Triricum durum) subjected to composting and artificial aging. The susceptibility to fungal growth, cytotoxicity and antibacterial properties were also examined. The biodegradation of the samples was investigated under normalized conditions simulating an intensive aerobic composting process. It was shown that the tested natural fillers significantly accelerate the biodegradation process of the composition (after 90 days mass loss of PBS 7%) and that the samples with WB degrade much faster (corresponding mass loss 86%) than those containing OP (corresponding mass loss 21%). The remains of the samples after composting were subjected to chemical structure analysis (FTIR), and their thermal properties were determined using differential scanning calorimetry (DSC). It was shown that the degree of crystallinity of PBS and composites increased with the increasing time of composting. In the case of pure PBS, this increase was a maximum of 31.5%, for biocomposite with OP 31.1% and for those containing WB 21.2%. FTIR results showed that cleavage of polymer chains by hydrolysis took place during composting. The tested samples were also subjected to artificial aging under conditions simulating solar radiation and were sprayed with water. After artificial aging, the significant changes in the color of the samples as well as the porosity of their surface was noted, which was mainly due to the effect of photodegradation of both the used OP and WB fillers. Additionally, FTIR analysis indicated that samples were degraded by photooxidation processes. The ability of fungi to grow on the surface of the samples was also tested. The results demonstrate the possibility of using the developed biocomposite materials as a carbon source for the growth of fungi. The antibacterial tests showed that samples containing OP exhibited strong antibacterial properties regardless of their wt.% content. Additionally, a cytotoxicity test was performed on a BJ cell line, demonstrating that none of the tested biocomposites were cytotoxic. Moreover, those with the addition of WB statistically significantly supported the viability of both fibroblast and bacteria cells, showing their biological safety but lack of antibacterial activity.

The Characterization and Development of Kenaf and Graphene Nanoplatelets in Polylactic Acid Composites

Kenaf fiber is in high demand due to the need for lightweight composites, particularly in the automobile industry and occasionally for interior building materials. Its remarkable strength and low density are the main causes of this. The use of natural fiber as a bio-composite material is limited because it is less heat resistant compared to synthetic fiber. To bolster the mechanical robustness of kenaf composites, graphene nanoplatelets (GnP) are incorporated as a supplementary reinforcing agent. Numerous studies have explored the mechanical properties of composites made from natural fibers and polymer matrices, with the recent market introduction of polylactic acid (PLA) polymers as biodegradable matrix options for biocomposites. The objective of this study is to determine the effects of incorporating graphene fillers on the tensile and flexural properties of PLA, kenaf, GnP composites. Hot pressing compression moulding is employed to fabricate the composite samples consisting of varying compositions, ranging from 95% PLA, 5% kenaf, and 0% GnP to 80% PLA, 15% kenaf, and 5% GnP. The result shows that adding 5% Graphene Nanoplatelets as a reinforcing filler will enhance the tensile strength and tensile modulus up to 18.2% and 53.2% respectively. While the flexural strength and flexural modulus enhanced up to 46.1% and 53.2% respectively. Besides that, DSC analysis shows that adding GnT does not alter the thermal properties of the composite with a melting point of 161.5 ℃. Overall, the results confirm that the addition of graphene improves the mechanical properties of the composites. It is suggested that further research should investigate the optimal ratio of GnP, kenaf, and PLA composition in order to achieve the optimum mechanical properties so that this composite has the potential to be used in various applications.

Synthesis and Antibacterial Evaluation of Chlorhexidine- and Triclosan-Impregnated Kaolinite Nanocomposites.

Clay minerals are actively used to obtain a bioactive composite. Kaolinite, as a representative of clay minerals, possesses unique properties essential for the creation of biocomposite materials. This mineral, characterized by its distinctive layered structure, is chemically inert, highly stable, thermally resistant, eco-friendly, biocompatible, and non-toxic. Kaolinite, which plays the role of a carrier in this work, has such properties and can be the basis for biologically active composites. Antibacterial composites, namely, kaolinite/chlorhexidine and kaolinite/triclosan, were synthesized by impregnation of calcined and non-calcined samples of natural kaolinite with the antibacterial agents chlorhexidine and triclosan. The structure, morphology, elemental composition, and mineralogical characteristics of the natural and synthesized kaolinite/chlorhexidine (KAO/CHX) and kaolinite/triclosan (KAO/TCS) composites were investigated by methods of analysis such as X-ray diffraction, FTIR (Fourier-transform infrared) spectroscopy, and scanning electron microscopy. The calcined kaolinite/chlorhexidine composite at 500 °C (KAO500°C/CHX) exhibited a higher content of antiseptics compared to the non-calcined kaolinite composite. The antibacterial activities of the kaolinite/chlorhexidine and kaolinite/triclosan composites were investigated against Gram-positive Staphylococcus epidermidis and Gram-negative Klebsiella pneumoniae and Escherichia coli strains by the well diffusion method and dilution method. The highest zone of inhibition was observed against Staphylococcus epidermidis (30.00 ± 0.00 mm and 30.67 ± 0.58 mm) by applying KAO/TCS and KAO500°C/TCS via the well diffusion method. The minimum bactericidal concentration of the kaolinite/TCS composite was 15.63 μg/mL for Staphylococcus epidermidis and Klebsiella pneumoniae.

ECOLOGICAL INNOVATION: THERMOSETTING RESINS AND WATER HYACINTH FIBER IN HIGH-PERFORMANCE BIO-COMPOSITE MATERIALS FOR SUSTAINABLE WASTE MANAGEMENT

<p style="text-align:justify; margin-bottom:11px"><span style="font-size:11pt"><span style="line-height:200%"><span style="font-family:Calibri,"sans-serif""><span lang="EN-US" style="font-size:12.0pt"><span style="line-height:200%"><span style="font-family:"Times New Roman","serif"">Fibrous plants are renewable resources that are abundant in nature. Economically and ecologically, it is especially advantageous to create high-performance composites using inexpensive natural fibres like water hyacinth (Eichhornea crassipes). As a composite matrix, remarkable thermosetting resins like polyester are frequently utilized because polymer composites have excellent dimensional stability, thermal stability, and mechanical qualities. For this investigation, hot curing and solution impregnation procedures were used to create several composites from water hyacinth fibre and polymer. This study's objective is to ascertain how the textures alter when PVC and bio composite components are included. This research is being done to find out what changes polymer materials with fiber-reinforced nanoparticles make. This study uses the water hyacinth (Eichornia crassipers) as a bio-composite material. This type of water hyacinth is usually only seen when the rivers are overflowing. The crystallinity index of water hyacinth fibre composite is 54.82%. The outside of the hyacinth composite is examined under a transmission electron microscope. Hyacinth fibre composite heat degradation is measured using the thermo gravimetric research technique. Additionally the result of this study is to find mechanical, chemical resistance, and morphological properties.</span></span></span></span></span></span></p>

A systematic in vitro study of the effect of normoglycaemic and hyperglycaemic conditions on the biochemical and cellular interactions of clinically-available wound dressings with different physicochemical properties.

Diabetic foot, leg ulcers and decubitus ulcers affect millions of individuals worldwide leading to poor quality of life, pain and in several cases to limb amputations. Despite the global dimension of this clinical problem, limited progress has been made in developing more efficacious wound dressings, the design of which currently focusses on wound protection and control of its exudate volume. The present in vitro study systematically analysed seven types of clinically-available wound dressings made of different biomaterial composition and engineering. Their physicochemical properties were analysed by infrared spectroscopy, swelling and evaporation tests and variable pressure scanning electron microscopy. These properties were linked to the interactions with inflammatory cells in simulated normoglycaemic and hyperglycaemic conditions. It was observed that the swelling behaviour and evaporation prevention at different glucose levels depended more on the engineering of the fibres than on the hydrophilicity and hydrophobicity of their biomaterials. Likewise, the data show that the engineering of the dressings as either non-woven or woven or knitted fibres seems to determine the swelling behaviour and interactions with inflammatory cells more than their polymer composition. Dressings presenting absorbent layers made of synthetic, non-woven fibres supported the adhesion of monocytes macrophages and stimulate the release of factors known to play a role in the chronic inflammation. Non-woven absorbent layers based on carboxymethyl cellulose mainly stimulating the iNOS, an enzyme producing free radicals; in the case of Kerracel this was combined with a swelling of fibres preventing the penetration of cells. Kaltostat, an alginate-based wound dressing, showed the higher level of swelling and supporte the adhesion of inflammatory cells with limited activation. Knitted dressings showed a limited adhesion of inflammatory cells. In conclusion, this work offers insights about the interactions of these wound dressings with inflammatory cells upon exudate changes thus providing further criteria of choice to clinicians.

Therapeutic and Environmental Potential of Mushrooms in Ancient and Modern Contexts: A Review.

Mushrooms are the healthiest, safest, most nutritious foods and are vital to human well-being. In historical contexts, religious teachings influenced the treatment of diseases, with ethnomycological knowledge suggesting that mushrooms held divine clues due to their unique appearances. The use of mushrooms was often linked to the "doctrine of signatures," where their morphological resemblance to human organs, such as the ear, kidney, and lungs, prompted researchers to theorize that products derived from mushrooms might be effective in treating health concerns. A wide variety of edible and wild mushrooms are now recognized for their bioactive compounds, which are valuable in biopharmaceuticals and dietary supplements. The compounds exhibit a range of therapeutic properties, encompassing immune enhancement, antioxidant effects, anti-inflammatory actions, antiviral capabilities, and anti-neoplastic activities. Modern science has corroborated many of these traditional insights, revealing mushrooms as sources of bioactive compounds with therapeutic potential. The intertwined filamentous mycelium of mushrooms is also attracting interest for its biocomposite uses in sustainable and environmentally friendly businesses. Biocomposite materials suitable for construction and building applications can be produced by creating a mycelial matrix or a self-forming adhesive using non-food fungal mycelia flour. This review explores the ethnomycological background, therapeutic potential, and innovative uses of mushroom mycelium in biocomposites, highlighting their role in health, wellness, and sustainable development.

Osteogenic Differentiation of Adipose Tissue-Derived Mesenchymal Stem Cells on Composite Polymeric Scaffolds: A Review.

The mesenchymal stem cells (MSCs) are the fundamental part of bone tissue engineering for the emergence of reconstructive medicine. Bone tissue engineering has recently been considered a promising strategy for treating bone diseases and disorders. The technique needs a scaffold to provide an environment for cell attachment to maintain cell function and a rich source of stem cells combined with appropriate growth factors. MSCs can be isolated from adipose tissue (ASCs), bone marrow (BM-MSCs), or umbilical cord (UC-MSCs). In the present study, the potential of ASCs to stimulate bone formation in composite polymeric scaffolds was discussed and it showed that ASCs have osteogenic ability in vitro. The results also indicated that the ASCs have the potential for rapid growth, easier adipose tissue harvesting with fewer donor site complications and high proliferative capacity. The osteogenic differentiation capacity of ASCs varies due to the culture medium and the addition of factors that can change signaling pathways to increase bone differentiation. Furthermore, gene expression analysis has a significant impact on improving our understanding of the molecular pathways involved in ASCs and, thus, osteogenic differentiation. Adding some drugs, such as dexamethasone, to the biomaterial composite also increases the formation of osteocytes. Combining ASCs with scaffolds synthesized from natural and synthetic polymers seems to be an effective strategy for bone regeneration. Applying exopolysaccharides, such as schizophyllan, chitosan, gelatin, and alginate in composite scaffolds enhances the osteogenesis potential of ASCs in bone tissue regeneration.

Heat distribution analysis of cartridge heater in core and cavity of compression mold for bio-composite roof tile fabrication

Bio-composite roof tiles use polypropylene matrix material and rice straw fiber as reinforcement processed by compression molding to create innovative and sustainable building products. This research aims to analyze heat distribution from the cartridge heater in the mold core during the compression molding process for fabricating bio-composite roof tiles. The research employs Finite Element Analysis (FEA), and laboratory experiments to measure temperature distribution and heating efficiency. The results showed that even heat distribution on the mold core is crucial to ensure optimal final product quality. Manual calculation estimated a heating time of 170.78 seconds to reach the desired temperature. Simulations conducted using Ansys R19.2 software shows that the temperature variation on the surface of the mold core can be minimized with the optimal placement of the heater cartridge. The simulation results obtained a time of 10 seconds to reach a temperature of 200℃ gradually. Laboratory experiments support the simulation results by showing that good heat distribution improves bio-composite tile materials' mechanical strength and homogeneity. This research significantly contributes to the design and optimization of mold cores for bio-composite applications. It offers practical guidance to the industry in improving the efficiency of the production process.

Potential development of thermally stable polycrystalline photovoltaic modules utilizing biocomposite materials

Abstract Solar energy has become a vital source for generating and harvesting electricity. Enhancing the efficiency of solar modules is an essential factor for successful transition to a sustainable and green energy production. Since natural fiber composites (NFCs) possess various outstanding properties, they can be used as an adequate alternative to synthetic fibers and environmentally harmful materials that are used in photovoltaic (PV) applications and module components. Solar modules are believed to undergo a decline in efficiency when exposed to excessive sun radiation, which eventually caused by a gradual escalation in temperature. Therefore, utilizing appropriate NFCs in the rear components and backsheets of solar modules could significantly contribute to the overall efficiency of these modules and enhance their thermal stability.

Effects of Polyvinyl Alcohol – Hydroxyapatite Composite Ceramic on Calvarial Defects with Critical Size in Rat Models

Introduction: Biodegradable composite biomaterials are essential in healthcare, effectively tackling numerous complex challenges. Bone reconstruction is a surgical procedure aimed at remedying segmental bone loss, which is notably complicated and often fails to heal properly. A novel bone graft substitute incorporating polyvinyl alcohol (PVA) and synthetic hydroxyapatite (HA) has been developed and is tested in vivo in calvarial defect models of rat. The present study aimed to evaluate the bone regeneration potential of PVA – HA composite bone graft. Materials and methods: A total of 24 adult male Wistar rats aged 12-15 weeks with an average weight of 150 grams were used in the current study. A 4 mm full-thickness critical-size defect was created on the parietal bone and filled with the pre-sized graft material. Radiography, micro-computed tomography, scanning electron microscopy, histology, and serum biochemical parameters, including alkaline phosphatase and acid phosphatase activity, were utilized to evaluate the healing potential of the graft material. The animals were observed for twelve weeks. An immediate postoperative dorsoventral view of the skull was exposed at day zero and subsequent radiographs were taken periodically at weeks 2, 4, 8, and 12 in a group including 24 animals. Results: Immediate post-operative radiographs revealed the radiolucent nature of the graft material. Throughout the healing process, it was observed that the graft remained in position and was intact. The values of serum biochemical parameters alkaline phosphatase and acid phosphatase activity) were haphazard throughout the observation period. In the 8th week, signs of progressive degradation of the graft material and bone regeneration could be seen, particularly on radiography, micro-CT scanning electron microscopy, and histologic examination. Conclusion: It is concluded that the test graft material successfully accelerated bone regeneration and completely integrated with the host bone at week 12 of the experiment in the rat model.

Natural Fibers from Vietnam Coffee Grounds as a Potential Reinforcement for Biocomposite Materials

Coffee grounds were a common agricultural byproduct available in large quantities in many countries, containing a relatively high cellulose content of approximately 26.6–31.3%. Extracting cellulose fibers from coffee grounds was therefore both economically and environmentally significant. This study aimed to extract cellulose fibers from coffee grounds using a non-toxic and cost-efficient alkaline hydrogen peroxide extraction method. Scanning electron microscopy (SEM) analysis results indicated that, after being dried, the cellulose fibers tended to aggregate into bundles, with no individual fibers observed. The extraction yield was found to be 63.24%. Fourier transform infrared (FTIR) spectroscopy analysis revealed absorption peaks at wavenumbers corresponding to O-H, C-H, and C-O-C group vibrations, characteristic of the chemical structure of cellulose. The crystallinity index determined by X-ray diffraction (XRD) technique of the extracted cellulose fibers was 38.9%, higher than that of the raw coffee grounds. Thermogravimetric analysis (TGA) result indicated that the thermal stability of the obtained cellulose fibers was relatively lower than that of the coffee grounds. The obtained cellulose fibers have potential application as a reinforcing agent for biocomposite materials.

Agro-industrial wastes and their application perspectives in metal decontamination using biocomposites and bacterial biomass: a review.

Contamination of water bodies is a significant global issue that results from the deliberate release of pollutants into the environment, especially from mining and metal processing industries. The main pollutants generated by these industries are metallic wastes, particularly metals, which can cause adverse effects on the environment and human health. Therefore, it is crucial to develop effective and sustainable approaches to prevent their discharge into the environment. Biofiltration is a technique used to remediate contaminated fluids using biological processes. Microorganisms and agro-industrial wastes have been used successfully as biosorbents. Hence, this review emphasizes the innovative use of agro-industrial waste reinforced with microbial biomass as bioadsorbents, highlighting their dual capacity for metal removal through various bioremediation mechanisms. The mechanisms at play in these biocomposite materials, which offer enhanced sustainability, are also analyzed. This study contributes to the advancement of knowledge by suggesting new strategies for integrating reinforced materials in biosorption processes, thus providing a novel perspective on the potential of lignocellulosic-based systems to improve decontamination efforts. On the other hand, it shows some studies where the optimization and scaling-up of biosorption processes are reported. Additionally, the implementation of multisystem approaches, leveraging multiple bioremediation techniques simultaneously, can further enhance the efficiency and sustainability of metal removal in contaminated environments.

Ecologic and economic motives for transforming calcium-based food wastes into sustainable value-added products: a review.

An overview of various industrial and bio-applications of unavoidable bio-waste materials reported in the literature over the last 25years is presented in this review. Calcium-based food wastes or "unavoidable bio-wastes" are hybrid bio-composite materials, consisting of a softer organic matrix surrounding a stiff mineralized ceramic phase. A wide range of different bio-wastes that are already in use or are investigated for multipurpose applications are presented. Bio-wastes hold considerable potential to contribute more widely to the circular management strategy through, for example, being processed to make new consumer products for a variety of applications, which include the use as a filler in polymers, biogenic hydroxyapatite, limestone or lime in construction products, nutritional feed supplements, soil-improving material and fertilizer, or precursor for making catalysts and adsorbents for the remediation of environmental contaminants. This review summarizes the results of various reported approaches with regard to the development of cost-effective value-added products from under-utilized food waste residues such as eggshells, seafood shells, and animal bones via a simple, eco-friendly, and economically viable approach. Therefore, the work is an advancement toward the goal of achieving a sustainable product by ensuring a holistic design approach from bio-wastes to various salable products, where calcium-based food wastes can compete with non-renewable resources.

Synthesis of Rice Husk-Based Biocomposites Coated with Sodium Alginate and Their Use in Congo Red Dye Adsorption

In this study, synthesis of a sodium alginate-coated rice husk-based biocomposite as a substitute adsorbent to lessen the negative impacts of Congo red dye was conducted. A calcium chloride (CaCl2) solution was used in the sonication and encapsulation processes to produce the biocomposite material. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM), and Fourier Transform Infrared (FTIR) Spectroscopy were used to characterize the biocomposite material. Adsorption experiments showed that the optimum pH was 3 and the dye concentration was varied between 10 and 50 ppm and adsorbent mass between 0.05 and 1.5 grams. Adsorption kinetics followed the pseudo-second-order linear model, while the adsorption isotherm model matched the Freundlich model. According to these results, biocomposites of rice husk and sodium alginate has a potential to be an environmental-friendly way to manage the textile waste.

Mechanical and Thermal Properties of Cellulose Nanocrystal/Graphene Nanoplatelet Reinforced Polylactide Acid Biocomposites

In this research, cellulose nanocrystal (CNC) and graphene nanoplatelet (GNP) were introduced as hybrid nanofillers at a total loading level of 5wt.% in poly(lactic) acid (PLA) as matrix material. PLA-CNC/GNP biocomposites were successfully fabricated with the utilisation of compression moulding to study the effect of CNC and GNP on the mechanical and thermal properties of the biocomposites. The produced PLA-CNC/GNP biocomposite materials, including pure PLA for comparison purposes, were characterised by mechanical and thermal properties. Overall, the results of the flexural properties showed that the PLA biocomposite had a formulation of 2.5 wt.% CNC and 2.5 wt.% GNP contributed significantly to the enhancement of flexural strength and the modulus, up to 47% and 76%, respectively. The thermal properties also seem to be optimally improved as the thermal stability of the biocomposite samples was analysed accordingly. Overall, the incorporation of CNC and GNP with 5 wt.% of total hybrid filler loading showed a favourable impact on the mechanical and thermal properties of PLA biocomposite for environmentally friendly automotive components.

Design of composite chitosan/algae/zeolite by freeze- or air-drying: A comparative adsorbent analysis for optimized removal of brilliant green dye.

A bio-composite material was developed that contains chitosan, food-grade algae, and zeolite for the removal of brilliant green (BG) dye. The synthesized bio-composite was dried via two different methods (air-drying; AD, and freeze-drying; FD). The physicochemical characterization of air-dried chitosan-algae-zeolite (Cs-Alg-Zl-AD) and freeze-dried chitosan-algae-zeolite (Cs-Alg-Zl-FD) were investigated by spectroscopy (FTIR, SEM-EDX, and XPS), diffraction (XRD), surface charge via pHpzc, specific surface area (SSA) and elemental analyses. The utilization of Box-Behnken Design (BBD) was intended to optimize the three input variables, which are adsorbent dosage, medium pH, and contact time. The adsorption optimization process yielded optimal conditions, which were verified through a desirability test and implemented in batch-mode equilibrium experiments. The Cs-Alg-Zl-FD has a higher specific surface area (SSA = 3.29 m2/g) compared to Cs-Alg-Zl-AD (SSA = 1.79 m2/g). The Cs-Alg-Zl-FD shows greater adsorptive removal of BG (98.6 %) over Cs-Alg-Zl-AD (88.6 %), in parallel agreement with differences in the SSA. Moreover, the maximum BG dye adsorption capacities of Cs-Alg-Zl-FD (119.5 mg/g) and Cs-Alg-Zl-AD (108 mg/g) at pH = 8.1 and 25 °C. The Freundlich model fits best with Cs-Alg-Zl-AD while Langmuir and Temkin models account for the Cs-Alg-Zl-FD dye adsorption. The Cs-Alg-Zl-FD shows greater dye adsorption over four adsorption cycles, as compared with the Cs-Alg-Zl-AD.