Search

The emerging concepts of sustainable textiles and controlled production strategy demands ideally zero emissions of contaminants into the aquatic environment. However, the currently in-practiced conventional processes in textiles dispose of a number of contaminants especially super toxic synthetic dyes as effluents. In recent years, nanomaterials have become attractive choice for eco-friendly removal of organic dyestuff. Accordingly, this article reports synthesis and characterization of biocomposite wherein copolymer of polyaniline (PANI) and Polypyrrole (PPY) was grafted onto hydroxyethyl cellulose (HEC). Further, adsorption properties of as-prepared composite were evaluated using textile dyes Rhodamine B (RhB) and methyl Orange (MO)- as model adsorbate. The characterization of novel biocomposite (HEC/PANI-PPy) was carried out using Fourier Transform Infrared (FT-IR), Brunauer-Emmett-Teller analyzer (BET), Scanning Electron Microscope (SEM), and powder X-ray diffraction (XRD). The operational parameters such as dye initial concentration, adsorbent amount, pH and contact time were also studied to evaluate the efficiency level of the prepared biocomposite. Interestingly, the composite-mediated adsorption of RhB and MO followed pseudo-second order and the Langmuir isotherm. It is found that the adsorption capacity HEC/PANI-PPy is 30.06 and 29.3 for RhB and MO respectively. Thus, HEC/PANI-PPy is an inexpensive and highly efficient adsorbent that could be employed for could be employed for the separation and removal of toxic organic dyes from polluted textile effluents. [ABSTRACT FROM AUTHOR]

In situ facile synthesis and the characterization of nanohydroxyapatite/chitosan (nHAP/CS) biocomposites were investigated for examining their potential applications in orthopedic implant technology. Firstly, the bare nHAP, europium-doped hydroxyapatite (Eu-nHAP), yttrium-doped hydroxyapatite (Y-nHAP), and Eu- and Y-codoped hydroxyapatite (Eu,Y-nHAP) nanoparticles were synthesized by the wet precipitation technique using biowaste-eggshell-derived calcium oxide powders. Then, through ultrasonication using the nanohydroxyapatite/chitosan mixtures (molar ratio = 1:2), the nHAP/CS, Eu-nHAP/CS, Y-nHAP/CS, and Eu,Y-nHAP/CS biocomposites were fabricated. Among them, Eu,Y-nHAP/CS showed higher cell viability (94.9%), higher solubility (pH = 7.6 after 21 days), and greater antibacterial activity than those of the other composites. In addition, Eu,Y-nHAP/CS exhibited improved mechanical properties compared with the other composites. For example, the nanoindentation test displayed the Eu,Y-nHAP/CS-coated 316L stainless steel implant to possess a higher Young's modulus value (9.24 GPa) and greater hardness value (300.71 MPa) than those of the others. The results indicate that the biomass-eggshell-derived Eu,Y-doped nHAP is of good use for orthopedic implant applications. [ABSTRACT FROM AUTHOR]

Water supply to millions of people worldwide is of alarmingly poor quality. Supply sources are depleting, whereas demand is increasing. Health problems associated with water consumption exceeding 1.5 mg/L of fluoride are a severe concern for the World Health Organization (WHO). Therefore, it is urgent to research and develop new technologies and innovative materials to achieve partial fluoride reduction in water intended for human consumption. The new alternative technologies must be environmentally friendly and be able to remove fluoride at the lowest possible costs. So, the use of waste from lignocellulosic biomasses provides a promising alternative to commercially inorganic-based adsorbents—published studies present bioadsorbent materials competing with conventional inorganic-based adsorbents satisfactorily. However, it is still necessary to improve the modification methods to enhance the adsorption capacity and selectivity, as well as the reuse cycles of these bioadsorbents. [ABSTRACT FROM AUTHOR]

The development of new materials is currently focused on replacing fossil-based plastics with sustainable materials. Obtaining new bioplastics that are biodegradable and of the greenest possible origin could be a great alternative for the future. However, there are some limitations—such as price, physical properties, and mechanical properties—of these bioplastics. In this sense, the present work aims to explore the potential of lignin present in black liquor from paper pulp production as the main component of a new plastic matrix. For this purpose, we have studied the simple recovery of this lignin using acid precipitation, its thermoplastification with glycerin as a plasticizing agent, the production of blends with poly(caprolactone) (PCL), and finally the development of biocomposite materials reinforcing the blend of thermoplastic lignin and PCL with stone groundwood fibers (SGW). The results obtained show that thermoplastic lignin alone cannot be used as a bioplastic. However, its combination with PCL provided a tensile strength of, e.g., 5.24 MPa in the case of a 50 wt.% blend. In addition, when studying the properties of the composite materials, it was found that the tensile strength of a blend with 20 wt.% PCL increased from 1.7 to 11.2 MPa with 40 wt.% SGW. Finally, it was proven that through these biocomposites it is possible to obtain a correct fiber–blend interface. [ABSTRACT FROM AUTHOR]

This study investigated the effects of poly(butylene-succinate) (PBS) and cassava pulp (CP) at two particle sizes (250 and 400 µm) on the properties of PBS/CP biocomposites. The PBS/CP biocomposites with different ratios (PBS100/CP0, PBS90/CP10, PBS80/CP20, PBS70/CP30, and PBS60/CP40) were prepared using a twin-screw extruder and formed using a ram extruder. The physical, mechanical, and biodegradable properties of these biocomposites were studied. The results showed that the melt flow index of biocomposites significantly decreased with an increase in the CP content as observed in both CP particle sizes. It was also observed that using 400 µm CP in PBS80/CP20 led to a higher melt flow index as compared to using 250 µm CP. The PBS/CP biocomposites were shown to improve Young's modulus and hardness. Nevertheless, tensile strength, elongation at break, and impact strength of the PBS/CP biocomposites decreased with an increase in the amount of CP (in both particle sizes). The addition of 250 µm CP provided good particle dispersion and compatibility in the biocomposite matrix. An increase in the CP content of up to 40% showed that the biocomposites had more brittle fracture although they were also the best biodegradable as indicated by natural soil burial test for 42 days. A biocomposite from PBS/CP could be useful in commodity packaging, outdoor plant pots, and injection molding as eco-friendly, strong and biodegradable materials. [ABSTRACT FROM AUTHOR]

Biomass is a material that can be potentially used as a natural fiber resource. Rice husk (RH) and sugarcane bagasse (SB), respectively containing 36.6% and 60% cellulose, are fibers that have the potential for biocomposite formation. In this study, an amine magnetic biocomposite (B-MNH2) was prepared by a one-step solvothermal reaction. Delignified RH and SB fibers at a ratio of 1:1 were added to a mixture of ethylene glycol, iron chloride, and 1,6-hexanediamine, and kept in a stainless steel autoclave reactor at 200 °C for 6 h. The obtained B-MNH2 contained 64.5% of Fe and 2.63 mmol/g of amine. Its surface area increased significantly from 9.11 m2/g to 25.81 m2/g after amine functionalization, and its optimum adsorption for Pb(II) ions was achieved within 360 min at 596.82 mg/g and pH 5. Moreover, the pseudo-first-order mechanism fitted well to the adsorption model. Other parameters, such as chemical oxygen demand (COD), total suspended solid (TSS), and dye during adsorption were also reduced by about 67.7%, 95.6%, and 89%, respectively. B-MNH2 showed a slight decrease in performance by only 8% after the fourth repeated use. The amine magnetic biocomposite led to the development of a potential adsorbent due to the high surface area, stable material, and easy separation, and was capable of absorbing contaminants from an aqueous solution. [ABSTRACT FROM AUTHOR]

In order to evaluate the influence of a different assembly of biocomposites of polyvinyl alcohol (PVOH), whey protein isolates (WPI), and nano‐silica (NS), a bilayer film treated with corona discharge was produced through a two‐step lamination. The first layer of PVOH/NS, treated with up to 90 s of discharge, and the second layer of WPI/NS, the bilayer films had their morphology, tensile strength, and water barrier investigated and compared to a single layer PVOH/WPI/NS film. Corona discharge increased the wettability of the first layer, improving the ability to interact with the second layer, thus increasing the adherence between these layers. Films treated with higher times of discharge showed a homogeneous transition between phases, suggesting compatibility, and adherence between layers. At 90 s of corona discharge treatment, bilayer films showed a tensile strength 72% higher than the bilayer film not treated and also 23% more resistant and 7.4 times more ductile than the single‐layer film. The lamination process and corona treatment increase the affinity of water with film constituents, thus leading to a higher permeability. The use of corona discharge associated with the lamination of PVOH/WPI/NS biocomposites provides a bilayer film and produces a more resistant, flexible, and ductile biocomposite film for packaging. [ABSTRACT FROM AUTHOR]

The aim of the present research was the development of a management method for wood-processing waste that was obtained during the production of parquet flooring. Currently mostly useless, such waste mainly ends up in landfills. The oak waste flour was used as a reinforcement material for epoxy biocomposites based on the polyaddition product of epoxidized soybean oil and bisphenol-A (ESBO_BPA). The biofiller was subjected to mercerization, acetylation, and diisocyanate modification to increase the typically poor compatibility between the highly hydrophilic wood fibers and the hydrophobic polymer matrix. Among the analyzed epoxy biocomposites, which contained about 60% raw materials of natural origin, it was found that the best mechanical properties were recorded for cured samples of the ESBO_BPA composition filled with 5 wt % of oak flour mercerized using a 5% solution of NaOH. It was also proven that a higher concentration of alkali deteriorated the mechanical-strengthening properties of the wood filler. The acetylation of the biofiller independently in the best elimination of hydroxyl groups from its structure also removed irregular strips and smoothed its surface. This resulted in a poorer wettability of the oak flour surface by the polymer and consequently an easier pullout of the filler from the polymer matrix and worse mechanical properties of the wood/epoxy composite. To the best of the authors' knowledge, the present research was the first to examine the possibility of the application of parquet flooring post-production wood flour in biomaterials based on a polyaddition product of epoxidized soybean oil and bisphenol-A. [ABSTRACT FROM AUTHOR]

This study aimed to develop injectable chitosan oligosaccharide (COS) and bovine hydroxyapatite (BHA) hybrid biocomposites, and characterise their physiochemical properties for use as a dental pulp-capping material. The COS powder was prepared from chitosan through hydrolytic reactions and then dissolved in 0.2% acetic acid to create a solution. BHA was obtained from waste bovine bone and milled to form a powder. The BHA powder was incorporated with the COS solution at different proportions to create the COS–BHA hybrid biocomposite. Zirconium oxide (ZrO2) powder was included in the blend as a radiopacifier. The composite was characterised to evaluate its physiochemical properties, radiopacity, setting time, solubility, and pH. Fourier-transform infrared spectroscopic analysis of the COS–BHA biocomposite shows the characteristic peaks of COS and hydroxyapatite. Compositional analysis via ICP-MS and SEM-EDX shows the predominant elements present to be the constituents of COS, BHA, and ZrO2. The hybrid biocomposite demonstrated an average setting time of 1 h and 10 min and a pH value of 10. The biocomposite demonstrated solubility when placed in a physiological solution. Radiographically, the set hybrid biocomposite appears to be more radiopaque than the commercial mineral trioxide aggregate (MTA). The developed COS-BHA hybrid biocomposite demonstrated good potential as a pulp-capping agent exhibiting high pH, with a greater radiopacity and reduced setting time compared to MTA. Solubility of the biocomposite may be addressed in future studies with the incorporation of a cross-linking agent. However, further in vitro and in vivo studies are necessary to evaluate its clinical feasibility. [ABSTRACT FROM AUTHOR]

This work investigates the rheological behavior and characteristics of solutions and convened biopolymer films from Chitosan (Chi) modified by kombucha-derived bacterial cellulose (KBC). The Arrhenius equation and the Ostwald de Waele model (power-law) revealed that the Chi/KBC solutions exhibited non-Newtonian behavior. Both temperature and KBC concentration strongly affected their solution viscosity. With the selection of a proper solvent for chitosan solubilization, it may be possible to improve the performances of chitosan films for specific applications. The elasticity of the prepared films containing KBC 10% w/w was preferable when compared to the controls. FTIR analysis has confirmed the presence of bacterial cellulose, chitosan acetate, and chitosan lactate as the corresponding components in the produced biopolymer films. The thermal behaviors of the Chi (lactic acid)/KBC samples showed slightly higher stability than Chi (acetic acid)/KBC. Generally, these results will be helpful in the preparation processes of the solutions and biopolymer films of Chi dissolved in acetic or lactic acid modified by KBC powder to fabricate food packaging, scaffolds, and bioprinting inks, or products related to injection or direct extrusion through a needle. [ABSTRACT FROM AUTHOR]

Bone defects have prompted the development of biomaterial-based bone substitutes for restoring the affected tissue completely. Although many biomaterials have been designed and evaluated, the combination of properties required in a biomaterial for bone tissue engineering still poses a challenge. In this study, a chitosan–silica-based biocomposite was synthetized, and its physicochemical characteristics and biocompatibility were characterized, with the aim of exploring the advantages and drawbacks of its use in bone tissue engineering. Dynamic light scattering measurements showed that the mean hydrodynamic size of solid silica particles (Sol-Si) was 482 ± 3 nm. Scanning electron microscopy of the biocomposite showed that Sol-Si were homogenously distributed within the chitosan (CS) matrix. The biocomposite swelled rapidly and was observed to have no cytotoxic effect on the [3T3] cell line within 24 h. Biocompatibility was also analyzed in vivo 14 days post-implant using a murine experimental model (Wistar rats). The biocomposite was implanted in the medullary compartment of both tibiae (n = 12). Histologically, no acute inflammatory infiltrate or multinucleated giant cells associated to the biocomposite were observed, indicating good biocompatibility. At the tissue–biocomposite interface, there was new formation of woven bone tissue in close contact with the biocomposite surface (osseointegration). The new bone formation may be attributed to the action of silica. Free silica particles originating from the biocomposite were observed at the tissue–biocomposite interface. According to our results, the biocomposite may act as a template for cellular interactions and extracellular matrix formation, providing a structural support for new bone tissue formation. The CS/Sol-Si biocomposite may act as a Si reservoir, promoting new bone formation. A scaffold with these properties is essential for cell differentiation and filling a bone defect. [ABSTRACT FROM AUTHOR]

The conventional disposal of green straws through burning can be eliminated in a biorefinery that converts them into a range of sustainable commercial products. However, this leads to the generation of green straw biorefinery effluent (GSBE). Green straw biorefineries discharge wastewater into the ecosystem that contains high concentrations of COD and NH4+−N. It is one of the most notable sources of visual pollution and disruption of aquatic life as well as public health that requires treatment prior to discharge. To improve the GSBE quality for environmental sustainability, the attainment of sustainable development goals 6, 9, and 14, "clean water and sanitation", "inorganic and organic waste utilization for added values from material", and "life below water" is very important. Therefore, the effectiveness of the continuous mode activated sludge (CMAS) system and the biocomposite-based–continuous mode activated sludge (SB-CMAS) system in the treatment of GSBE was investigated in this study. Response surface methodology (RSM) was used to optimize the process variables. At their optimized conditions, the performances of CMAS and SB-CMAS were analyzed in terms of COD and NH4+−N. Findings showed 81.21% and 95.50% COD and 78.31% and 87.34% NH4+−N reduction in concentration for CMAS and SB-CMAS, respectively. The high COD and NH4+−N removal efficiencies indicate the better performance of CMAS and SB-CMAS. The first- and second-order models and the modified Stover–Kincannon biokinetic models were utilized to analyze substrate removal rates. It was discovered that the modified Stover models were ideal for the measured data with R2 values 0.99646 and 0.91236 attained for COD and NH4+−N, respectively, in CMAS. The SB-CMAS had 0.99932 and 0.99533 for COD and NH4+−N, respectively. Maximum contaminant elimination was attained at 60% GSBE and 2-day HRT. Thus, to achieve the UN SDGs for 2030, findings from this study have the potential to answer goals 6, 9, and 14. [ABSTRACT FROM AUTHOR]

Thermomechanical pulp (TMP) fibres can serve as renewable, cost-efficient and lightweight reinforcement for thermoplastic polymers such as poly(lactic acid) (PLA). The reinforcing ability of TMP fibres can be reduced due to various factors, e.g., insufficient dispersion of the fibres in the matrix material, fibre shortening under processing and poor surface interaction between fibres and matrix. A two-level factorial design was created and PLA together with TMP fibres and an industrial and recyclable side stream were processed in a twin-screw microcompounder accordingly. From the obtained biocomposites, dogbone specimens were injection-moulded. These specimens were tensile tested, and the compounding parameters statistically evaluated. Additionally, the analysis included the melt flow index (MFI), a dynamic mechanical analysis (DMA), scanning electron microscopy (SEM) and three-dimensional X-ray micro tomography (X- μ CT). The assessment provided insight into the microstructure that could affect the mechanical performance of the biocomposites. The temperature turned out to be the major influence factor on tensile strength and elongation, while no significant difference was quantified for the tensile modulus. A temperature of 180 °C, screw speed of 50 rpm and compounding time of 1 min turned out to be the optimal settings. [ABSTRACT FROM AUTHOR]

A series of eco-friendly biocomposites with improved mechanical properties and interfacial interaction were prepared by melt-mixing natural fibers using a cellulose acetate derivative as a polymer matrix and used to evaluate their mechanical, thermal, and morphological properties. The natural fiber used as a biofiller was pre-surface-treated by a refining process using alkali and natural enzymes to improve compatibility and increase interfacial bonding with biopolymer substrate. To increase the processability of the cellulose material, the raw material was plasticized and the composition prepared in the form of pellets in a twin-screw extruder by mixing with an additive before being molded through an injection process. For each composition, the interfacial bonding force between different materials was confirmed through morphology analysis and evaluation of mechanical and thermal properties. When biofillers and a viscosity modifier were used at the same time, the fabricated biocomposites had controllable crystallinity, stiffness, and elasticity and showed improved mechanical strength, such as tensile strength and flexural strength. These results indicated that interfacial properties could be increased through interfacial interactions between two different components due to appropriate surface treatment. In addition, it was confirmed that a composition having interfacial interaction, not a simple mixture, could be prepared by lowering both glass transition and melting temperature. The lowering of glass transition temperature increased the elasticity of the biocomposites, which have the potential advantage of easier melt processing when applied to various injection parts. [ABSTRACT FROM AUTHOR]

In engineering applications, natural fiber composites must comply with fire requirements including the use of flame retardant. Furthermore, biocomposites are known to be water sensitive. Whether flame retardants affect the water sensitivity and whether water absorption affects the fire behavior and the mechanical performance of biocomposites are the two main topics addressed in this work. In this study, a flax fiber/epoxy composite flame retardant with 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) or aluminum diethyl phosphinate (AlPi) was aged in humid atmosphere or by immersion in water. Water absorption kinetics revealed that DOPO induces an increase in equilibrium water content by approximately a factor of 2 due to its intrinsic hygroscopicity and/or its plasticizing effect on the epoxy matrix. In contrast, AlPi does not significantly change the water sensitivity of the biocomposite. Mechanical testing highlighted that, whatever the FR, the evolution of mechanical properties with ageing is governed by the moisture content. The drop of elastic modulus was attributed to a decrease in fiber rigidity due to plasticization, while the increase in tensile strength was assigned to an increase in fiber/matrix friction due to fiber swelling. As regards flame retardancy, only the highest water contents modified the fire behavior. For the AlPi containing biocomposite, the water release resulted in an increase by 50% of the time to ignition, while for the DOPO flame retardant biocomposite the water release was mainly postponed after ignition. [ABSTRACT FROM AUTHOR]

All-cellulose composites (ACCs) are manufactured using only cellulose as a raw material. Biobased materials are more sustainable alternatives to the petroleum-based composites that are used in many technical and life-science applications. In this study, an aquatic NaOH-urea solvent system was used to produce sustainable ACCs from wood-based woven textiles with and without the addition of TEMPO-oxidized nanocellulose (at 1 wt.-%). This study investigated the effects of dissolution time, temperature during hot press, and the addition of TEMPO-oxidized nanocellulose on the mechanical and thermal properties of the composites. The results showed a significant change in the tensile properties of the layered textile composite at dissolution times of 30 s and 1 min, while ACC elongation was the highest after 2 and 5 min. Changes in hot press temperature from 70 °C to 150 °C had a significant effect: with an increase in hot press temperature, the tensile strength increased and the elongation at break decreased. Incorporating TEMPO-oxidized nanocellulose into the interface of textile layers before partial dissolution improved tensile strength and, even more markedly, the elongation at break. According to thermal analyses, textile-based ACCs have a higher storage modulus (0.6 GPa) and thermal stabilization than ACCs with nanocellulose additives. This study highlights the important roles of process conditions and raw material characteristics on the structure and properties of ACCs. [ABSTRACT FROM AUTHOR]

Natural fibre biopolymer composites with both fibres and matrix being derived from biomaterials are increasingly used in demanding applications, such as sensing, packaging, building, and transport, and require good electrical, thermal, and flame retardant properties. Herein, an investigation of the effectiveness of functionalising nonwoven cotton/poly(lactic acid) (PLA) fibre mats with graphene oxide nanosheets has been reported by using a facile dip-coating method followed by thermal reduction for enhancing the electric, thermal, and abrasion-resistance properties. The manufacturing processes for preparing biocomposites and introducing functionality are readily scalable. Experimental results reveal that with the addition of less than 0.5 wt% graphene nanoplatelets, the biocomposites showed significant improvements in abrasion resistance, electrical conductivity, thermal conductivity, and diffusivity. Furthermore, the composite shows excellent piezo-resistivity to act as strain sensors with a gauge factor of 2.59 at strains up to 1%. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) has been used in packaging applications due to its biocompatibility and biodegradability. However, this non-toxic synthetic material belonging to a highly hydrophilic polymer has poor resistance to wet environments, no antibacterial activity, and low tensile and thermal properties. This study aims to prepare and characterize a PVA-based biocomposite film mixed with antimicrobial white ginger nanocellulose (GCNF) and zinc oxide (ZnO) nanoparticles. The film was processed using GCNF (0.1 g) or/and ZnO nanoparticles (0.5 g). The results confirm that the GCNF/ZnO/PVA-based film presents the strongest antimicrobial activity and the highest thermal resistance. This film also had the best value in tensile strength (19.7 MPa) and modulus (253.1 MPa); 63.9% and 117.9%, respectively higher than purce PVA. Its elongation at break was 56.6%, not statistically significantly different from the pure PVA film. Thus, this PVA-based hybrid biocomposite film reinforced by GCNF and ZnO has excellent potential for fresh food packaging in industrial applications. [ABSTRACT FROM AUTHOR]

In this study, biologically degummed okra bast and corn husk fibers were subjected to alkalization processes. Alkalization treatments resulted in decrease of linear density of the biologically degummed fibers. Increment in alkali concentration resulted in an initial increase then a successive decrease in all tensile indicators: initial modulus, breaking tenacity and breaking elongation. 3 g/L NaOH-treated fibers showed the best tensile characteristics for both okra bast and corn husk fibers. The IR spectra analysis suggested elimination of extracellulosic materials upon alkaline treatment. The ranges for properties of the produced okra bast and corn husk fibers can be summarized in consecutive order as linear density of 9.7–12.3 and 20.0–24.3 tex; initial modulus between 1257-1897 and 156.4–354.6 cN/tex; breaking tenacity range in 28.0–46.8 and 6.37–15.2 cN/tex; and elongation in the range 2.0–2.5% and 8.7–19.9%. The properties of obtained okra bast fibers are found to be superior to corn husk fibers and comparable to that of conventional bast fibers.

Surface modification of a jute fibrous reinforcement is preferred to improve its compatibility with thermosetting resin for the development of biocomposite. A plain weave jute fabric was chemically modified with different concentrations of sodium hydroxide (NaOH) i.e. 1 to 6% (weight/volume). The chemically modified jute fabrics were assessed for their physical, mechanical, and morphological properties. The modified jute reinforcements were used for the preparation of biocomposite by hand laying method cum compression molding method, and the respective biocomposites were evaluated for their physical and mechanical properties. Results inferred that NaOH modified the fine structure and morphological properties of treatment on jute reinforcement and the reinforcing ability of the modified jute fabric is increased with increasing in the concentration of NaOH up to 5% (w/v) and then stabilized. It is concluded that the suitable concentration for improved reinforcement is found at 5% (w/v) at 30°C for 60 min in 1:15 material-to-liquor ratio.

The current study is aimed to develop a green packaging material out of betel nut fiber waste that holds up to the values of commercial food packaging. Biocomposites of betel nut fiber were prepared with varying fiber concentrations of 9, 10 and 12% and subjected to utility-based mechanical, physical, morphological and storability tests using chilies for storage. The composite with 10% fiber content exhibited superior strength features with tensile strength, compressive strength, elastic modulus, nanohardness and minimum creep rate values of 1.59 MPa, 426.23 MPa, 2.032 GPa, 99.729 MPa and 37.02, respectively. It possessed a characteristic elasto-plastic and stress-strain behavior, favorable for storage and transportation. Along with the superior mechanical properties, the selected composite manifested a lower water vapor permeability of 4.635 × 10−9 g/msPa and a minimal sorption capacity of 51.01% in comparison with cardboard sheets (currently used packaging material for chilies). Chilies stored in developed betel nut fiber composite exhibited a significantly higher value of firmness and reduced value of degradation factors as compared to that in cardboard boxes. Hence, it can be concluded that bearing all the superior properties, the developed composite is more functional than the cardboard cartons for storage and transportation.

[Display omitted] • Nanostructured Boost: Nano strontium hydroxyapatite (nSrHA) enhances biocomposite strength and stability. • Osteogenic phytochemical-enriched biocomposites show promise for bone regeneration. • Cytocompatibility, controlled release of BM, improved degradation, and increased mechanical strength due to nSrHA incorporation. • Biocomposites significantly boost rADMSC proliferation and viability. • Safe, effective scaffolds ideal for non-load-bearing/maxillofacial reconstructive surgeries. Biocomposite materials, composed of biodegradable polymers and supplements, are promising for bone regenerative matrices due to their mechanical strength and excellent osteoconductivity. This study focuses on fabricating electrospun composite scaffolds using the bark extract of Butea monosperma (BM), nano strontium hydroxyapatite (nSrHA), and polycaprolactone (PCL). Four types of scaffolds were prepared: PCL (control), BM-PCL, nSrHA-PCL, and BM-nSrHA-PCL. The scaffolds were evaluated through various techniques: bright field microscopy for standardization, SEM for structural evaluation, and SEM-EDX for elemental analysis. Additionally, mechanical strength, release study, degradation, and protein adsorption were assessed. Furthermore, cytotoxicity, proliferation, and cytocompatibility of the scaffolds were evaluated using rat adipose-derived mesenchymal stem cells (rADMSCs) through SEM, MTT assay, LDH assay, DAPI staining, and Direct contact assay. SEM analysis confirmed that all four fabricated scaffolds were nano-fibrous in nature. The incorporation of phytochemicals and nSrHA was confirmed via SEM-EDX. Mechanical testing revealed that the BM-nSrHA-PCL scaffolds had superior mechanical properties compared to the control PCL scaffolds. Protein adsorption studies indicated enhanced protein binding in BM-nSrHA-PCL scaffolds. Degradation studies showed that BM-nSrHA-PCL scaffolds had a controlled degradation rate suitable for tissue engineering applications. Cytotoxicity tests confirmed that all scaffolds were noncytotoxic. Proliferation and cytocompatibility assays demonstrated that BM-nSrHA-PCL scaffolds significantly promoted cell proliferation compared to other scaffold types. These results suggest that the BM-nSrHA-PCL scaffolds exhibit improved mechanical properties, protein adsorption, controlled degradation, and enhanced cell proliferation, making them promising candidates for bone tissue engineering applications. [ABSTRACT FROM AUTHOR]

Fiber-reinforced green composites made from natural plant fibers are an increasingly popular sustainable alternative to conventional high-performance composite materials. Given the variety of natural fibers themselves, and the even larger variety of possible composites with specific fiber dosage, fiber orientation distribution, fiber length distribution, and fiber–matrix bond characteristics, micromechanics-based modeling is essential for characterizing the macroscopic response of these composites. Herein, an analytical multiscale micromechanics model for elastic homogenization is developed, capable of capturing the variety. The model features (i) a nanoscopic representation of the natural fibers to predict the fiber stiffness from the universal stiffness of the fiber constituents, mainly cellulose, (ii) a spring-interface model to quantify the compliance of the fiber–matrix bond, and (iii) the ability to model any (and any combination of) orientation distribution and aspect ratio distribution. Validation is performed by comparing the predicted stiffness to experimental results for as many as 73 composites available in the literature. Extensive sensitivity analyses quantify the composite stiffening upon increasing fiber volume fraction, fiber alignment, fiber length, and fiber–matrix interface stiffness, respectively. [ABSTRACT FROM AUTHOR]

Pesticides can have harmful impacts on the environment and living organisms. Thus, removing them from polluted water is crucial. In this study, a bionanocomposite of carboxymethyl tragacanth- grafted -poly(3-aminophenol)/zinc oxide@iron oxide (CMT- g -P3AP/ZnO@Fe 3 O 4) synthesized by in situ copolymerization as an efficient adsorbent to eliminate the acetamiprid pesticide from polluted water. The CMT- g -P3AP/ZnO@Fe 3 O 4 magnetic nanocomposite was analyzed utilizing various techniques including FTIR, EDX, FESEM, XRD, BET, CHNSO, and TGA. The results displayed that the resulting nanocomposite with maximum adsorption capacity (Q max) successfully removed the acetamiprid pesticide from polluted water under optimal conditions such as pH of 7.00, 5.00 mg of adsorbent, 20.0 min duration, and 400 mg/L acetamiprid concentration. According to the linear Langmuir isotherm, the Q max of the biosorbent was 833 mg/g. The experimental adsorption data fitted well with Temkin's nonlinear isotherm model. The adsorption kinetic data were closely related to the Weber-Morris intraparticle diffusion nonlinear model. After three repetitive cycles, CMT- g -P3AP/ZnO@Fe 3 O 4 can be outstandingly renewed and recycled without significant reduction in its adsorption efficacy, as evidenced by the adsorption-desorption experiments. In addition, the CMT-g-P3AP/ZnO@Fe 3 O 4 displayed the good antibacterial activity against E. coli and S. aureus. [Display omitted] • Antibacterial magnetic bionanocomposite based on carboxymethyl tragacanth synthesized. • Antibacterial magnetic bionanocomposite used as a sorbent for acetamiprid removal. • Maximum adsorption capacity of the bionanocomposite for acetamiprid was 833 mg/g. • Bionanocomposite showed good antibacterial activity against E. coli and S. aureus. [ABSTRACT FROM AUTHOR]

This work reports on the development of collagen films with graphene oxide nanoparticles (GO NPs), aiming toward the development of a new generation of functional sustainable sensors. For this purpose, different GO NP contents up to 3 wt % were incorporated into a collagen matrix, and morphological, thermal, mechanical and electrical properties were evaluated. Independently of the GO NP content, all films display an increase in thermal stability as a result of the increase in the structural order of collagen, as revealed by XRD analysis. Further, the inclusion of GO NPs into collagen promotes an increase in the intensity of oxygen characteristic absorption bands in FTIR spectra, due to the abundant oxygen-containing functional groups, which lead to an increase in the hydrophilic character of the surface. GO NPs also influence the mechanical properties of the composites, increasing the tensile strength from 33.2 ± 2.4 MPa (collagen) to 44.1 ± 1.0 MPa (collagen with 3 wt % GO NPs). Finally, the electrical conductivity also increases slightly with GO NP content, allowing the development of resistive bending sensors.

The degradability of the biocomposite produced from a binary mixture of thermoplastic banana starch (TPS) and polycaprolactone (PCL) reinforced with fique fibers (Fs) was evaluated in three different environments (soil, compost, water). An experimental design with two factors (soil and compost) and three levels (5, 10, and 20 cm) was used, with additional tests for a third aqueous environment (water from the lake of the Universidad del Valle) at a depth of 20 cm. The biocomposite was prepared from the implementation of a twin-screw extrusion process of the binary mixture TPS/PCL and fique fibers (54, 36, and 10% composition, respectively), followed by hot compression molding, and after that, generating ASTM D638 type V specimens using a stainless-steel die. The specimens were dried and buried according to the experimental design, for a total experimental time of 90 days, and removing samples every 30 days. After 90 days, all samples showed signs of degradation, where the best results were obtained in the compost at a depth of 20 cm (34 ± 4% mass loss and a decrease in tensile strength of 77.3%, which indicates that the material lost mechanical properties). TPS was the fastest disappearing component and promoted the degradation of the composite material as it disappeared. Finally, the aqueous media presented the lowest degradation results, losing only 20% of its initial mass after 90 days of the experiment, being the least effective environment in which the biocomposite can end up.

Wood flour–poly(butylene succinate)–poly(lactic acid) biocomposite samples were prepared by fused-deposition-molding 3D-printing technology, and modifications with glycerol and a silane coupling agent (KH550) were carried out. The samples were then hydrothermally aged. Modification with glycerol and KH550 enhanced the hydrophilicity of the samples and increased their tensile strength. Hydrothermal aging clearly whitened the surfaces of all the samples and made them more hydrophobic. Meanwhile, their tensile properties and thermal stability became poor; a higher hydrothermal aging temperature affected the mechanical properties more negatively. The modified samples turned out to be more resistant to the hydrothermal aging, and modification with KH550 could improve the anti-hydrothermal aging properties of the samples better than that with glycerol, where the tensile properties and the cross-sectional morphologies of the fractured specimens were concerned. Generally, the effects of hydrothermal aging temperature on the physico-mechanical properties of the printed specimens were greater than those by hydrothermal aging time.

Wood–plastic composites (WPCs) represent composite materials that employ shredded wood combined with a thermoplastic substance, such as polylactic acid (PLA), to establish structural cohesion within the product profile. This amalgamation of materials results in a robust structure designed to fulfill specialized roles under the influence of pressure and temperature. Given the nature of the constituent materials, the resultant product can be classified as a biocomposite. The creation of such biocomposites entails a rigorous process necessitating the fine-tuning of specific parameters and suitable technologies. The foundational materials employed in this process must be both natural and biodegradable. However, it is noteworthy that natural components like fibers exhibit anisotropic behavior, wherein their mechanical attributes are contingent on the direction of the applied force. Consequently, predicting their performance during biocomposite production proves challenging. The principal objective of this study was to conduct a comparative analysis of wood-based composites incorporating PLA thermoplastic binding agents. The intention was to discern variations in density profiles arising from distinct measurement methodologies. Two measurement methods were used for the measurement: X-ray and spectrum desaturation. Additionally, the study sought to investigate the impact of introducing PLA additives at 25% and 50% concentrations on the fabrication of WPC from wood chips. The properties of these composites were assessed by considering the inherent traits of the composite materials.

The development of the paper industry has led to the discharge of a large amount of papermaking waste liquid containing lignosulfonate. These lignin black liquids cause a lot of pollution in nature, which runs counter to the current environmental protection strategy under the global goal. Through the development and use of lignosulfonate in papermaking waste liquid to increase the utilization of harmful substances in waste liquid, we aim to promote waste liquid treatment and reduce environmental pollution. This paper proposes a new strategy to synthesize novel glue-free biocomposites with high-performance interfacial compatibility from papermaking by-product sodium lignosulfonate/chitosan (L/C) and waste bamboo. This L/C bamboo biocomposite material has good mechanical properties and durability, low formaldehyde emissions, a high recovery rate, meets the requirements of wood-based panels, and reduces environmental pollution. This method is low in cost, has the potential for large-scale production, and can effectively reduce the environmental pollution of the paper industry, promoting the recycling of biomass and helping the future manufacture of glue-free panels, which can be widely used in the preparation of bookcase, furniture, floor and so on.

The dynamic development of the food industry and the growing interest of consumers in innovative solutions that increase the comfort and quality of life push the industry towards seeking pioneering solutions in the field of food packaging. Intelligent and active packaging, which affects the quality and durability of food products and allows one to determine their freshness, is still a modern concept. The aim of our study was to obtain two types of films based on chitosan and starch with micellar nanostructures containing extracts from turmeric rhizomes and hibiscus flowers. The presence of spherical nanostructures was confirmed using a scanning electron microscope. The structural and optical properties of the obtained composites were characterised by Fourier-transform infrared (FTIR), UltraViolet-Visible (UV-VIS), and photoluminescence (PL) spectroscopy. Scanning electron microscopy (SEM) analysis confirmed the presence of spherical micellar structures with a size of about 800 nm in the obtained biocomposites. The presence of nano-/microstructures containing extracts affected the mechanical properties of the composites: it weakened the strength of the films and improved their elongation at break (EAB). Films with nano-/microparticles were characterised by a higher water content compared to the control sample and lower solubility, and they showed stronger hydrophilic properties. Preliminary storage tests showed that the obtained biocomposites are sensitive to changes occurring during the storage of products such as cheese or fish. In addition, it was found that the film with the addition of turmeric extract inhibited the growth of microorganisms during storage. The results suggest that the obtained bionanocomposites can be used as active and/or intelligent materials.

The present investigation seeks to assess the impact of fillers on the mechanical characteristics of entirely biodegradable composites, introducing an advanced solution to fulfil long-term durability demands within point-of-purchase (POP) industries. The inclusion of calcium carbonate (CaCO3) fillers on the various properties of the flax fibre-reinforced composites, after accelerated irradiation in an ultraviolet (UV) radiation exposure has been investigated in the present study. Different types of flax fibre-reinforced poly lactic acid (PLA) biocomposites (with and without filler) were fabricated. The mechanical (tensile and flexural), and physical properties of the specimens were assessed after 500 h of exposure to accelerated UV irradiation of 0.48 W/m2 at 50 °C and were compared with those of the unexposed specimens. The results indicate that the presence of the inorganic filler significantly improved the performance of the biocomposites compared to the unfilled biocomposites after UV exposure. After adding 20% of fillers, the tensile strength was increased by 2% after UV degradation, whereas the biocomposite without filler lost 18% of its strength after UV exposure. This can be attributed to the change in the photo-degradation of the PLA due to the presence of the CaCO3 filler, which acts as a safeguard against UV light penetration by creating a protective barrier. The scanning electron microscopy (SEM) images of the degraded specimen surface show substantial difference in the surface topography of the composites with and without fillers.

This research work investigates the effects of the concentration and treatment of chopped false banana (Ensete ventricosum) fibres on the mechanical properties of a polypropylene matrix. The chopped false banana fibres (FBFs) were modified using Aloe Vera gel following treatment with 5% NaOH for 12 h at room temperature, with 1% acetic acid used to neutralise the remaining NaOH. FBF-reinforced polypropylene composite plates were then manufactured with 10, 20, 30, and 40 wt.% of chopped FBF. The mechanical properties were investigated using the compressive, impact, and three-point bending tests. Regarding the mechanical properties of the FBF-reinforced polypropylene composites, it was found that they have a maximum average compressive strength of 17.2 MPa. A maximum bending strength of 12.109 MPa was found for the Aloe Vera gel-treated composite with 30 wt.% of FBF. The maximum average compressive strength for this composite was 17.19 MPa. A maximum bending strength of 9.97 MPa for untreated composites was recorded for the composite with 10 wt.% of FBF. Finally, Aloe Vera-treated FBF-reinforced composites have better mechanical properties than untreated ones. The mechanical properties of Aloe Vera-treated FBF-reinforced polypropylene composites, as determined via impact, compressive and flexural tests, were superior for composites with 30 wt.% of FBF.

This paper deals with the study of the degradation of polylactic acid (PLA) material structures and biocomposite systems with a PLA matrix containing ground natural particulate waste fillers, buckwheat husks and egg shells. Waste fillers were used without difficult cleaning operations to describe the effect of the raw waste material on PLA. Biocomposites with raw waste materials are increasingly coming to the forefront in car interiors and packaging products. The prepared material systems were exposed to controlled climatic ageing simulating long-term solar radiation and cyclic outdoor conditions. The degradation of the biocomposite systems was evaluated via thermal (differential scanning calorimetry) and mechanical properties (tensile and flexural tests, Charpy impact toughness). In addition to evaluating the degradation of the material structures using standardized tests, the influence and effect of controlled climatic ageing was visually assessed using SEM images (electron microscopy) of the surfaces and fracture surfaces of the test specimens.

In this research, some physical and chemical properties of the biocomposite obtained from synthesized epoxy modified palm oil (MPO) and epoxy resin have been characterized. The experimental study plan is made according to Response Surface Methodology (RSM) and biocomposites with different MPO rates are obtained. The chemical bond structure of MPO and epoxy biocomposite has been evaluated with Fourier Transform Infrared Spektrofotometre (FTIR). The experimental, and RSM model results obtained, the density of the biocomposite rise as the MPO rate increases. It is determined that the Shore D hardness of the biocomposite is inversely proportional to the MPO rate by mass. The thermal conductivity coefficient and thermal stability also rise with the rate of MPO (wt.%) in the biocomposite. In the thermal degradation experiments of the obtained biocomposite, it is observed that the thermal stability of the composite goes up as the MPO rate rises. Activation energies are calculated using the Flynn Wall Ozawa, Kissinger, and Coats Redfern models. The activation energies calculated for the 9th, 2nd, and 13th experiments according to the Flynn Wall Ozawa method are approximately 139.65, 143.56, and 145.28 kJ/mol, respectively. The function with the highest R2 value has been determined according to the Coats Redfern method, and the deviation in Flynn Wall Ozawa and Kissinger model results was below 7%.

Pineapple leaves fibre (PALF) is one of the natural fibre that hashigh potential to substitute non-renewable synthetic fibre in thermoplastic products.The PALF were alkali treated withdifferent concentrationsof NaOH. Untreated and alkali treated PALF were characterizedusing Thermal Gravimetric Analysis (TGA)and Scanning Electron Microscopy (SEM)to determine the thermal stability and surface morphology of the fibres respectively. Biocomposites were prepared by reinforced alkali treated and untreated PALF withpolypropylene (PP) matrix. Tensile properties and water absorption analysis of PALF/PP biocomposites were studied.Biocomposite with 8 wt.% of alkali treated PALFexpress excellentthermal stability, with maximum degradation temperature at 270 °Cwhich is a 7.17% improvement compared to untreated PALF. This biocomposite alsohad increasedtensile strength(116 MPa)with 43%improvement compared to untreated PALF/PP(66 MPa)biocompositeand had lower water absorption at 6% compared to untreated biocomposite which at21%. Hence, alkali treated PALF is able to improve the characteristic of PALF and increase the compatibility between fibreand polymerby reducing hemicellulose and lignin components.

Abstract Background While mycelium is considered a promising alternative for fossil-based resins in lignocellulosic materials, the mechanical properties of mycelium composite materials remain suboptimal, among other reasons due to the weak internal bonds between the hyphae and the natural fibres. A solution could be provided by the hybridisation of mycelium materials with organic additives. More specifically, bacterial cellulose seems to be a promising additive that could result in reinforcing mycelium composites; however, this strategy is underreported in scientific literature. Results In this study, we set out to investigate the mechanical properties of mycelium composites, produced with the white-rot fungus Trametes versicolor, and supplemented with bacterial cellulose as an organic additive. A methodological framework is developed for the facile production of bacterial cellulose and subsequent fabrication of mycelium composite particle boards based on a hybrid substrate consisting of bacterial cellulose and hemp in combination with a heat-pressing approach. We found that, upon adding bacterial cellulose, the internal bond of the composite particle boards significantly improved. Conclusions The addition of bacterial cellulose to mycelium composite materials not only results in a strengthening of internal bonding of mycelium material, but also renders tuneable mechanical properties to the material. As such, this study contributes to the ongoing development of fully biological hybrid materials with performant mechanical characteristics.

Bone fracture caused by various incident causes medical problems. Then bone restoration is required. Bone grafts can be used to solve this problem. One of the materials that can be used to produce bone graft is PMMA. PMMA requires to be combined with other materials to extend the solidification time. The material that can be used for bone graft material is sago starch. The main ingredient composition of Biocomposite [sago/PMMA] consists of sago: PMMA = 1 : 1 (w/w). The composition of the addition of MMA is 10% (v/w) of PMMA, this is to extend the curing time. Thus the material can be through from the chamber extruder to the nozzle. This research aims to obtain combinations of 3D Printer FDM Customized machine parameters for minimizing of error dimension. The 3D Printer machine uses pneumatic system to push the material from the container to the chamber and used screw extruder to push the material out through the nozzle. The experimental design method used a 2k fractional factorial design, with 3 parameters, 2 levels and 3 responses. The experimental results obtained that the layer height parameter has a significant influence on the x-dimensional error. The optimization results obtained a combination of parameters to get the smallest error dimensions, the print speed is 25 mm/s, the layer height is 2.93 mm and the fill density is 20%. The results of optimization obtained that the x-dimensional error is 0.016, the y-dimensional error is 0.069 and the z-dimensional error is 0.4539.

Aiming to adds value to agricultural products and develop environmental-friendly and cost-effective materials, the present work investigates the influence of babassu mesocarp (BM) flour extractives and the addition of maleic anhydride-modified polyethylene (MAPE), as a coupling agent, on the properties of additivated polyhydroxybutyrate (PHBad)/BM biocomposites. The extractives were partially and completely removed from BM flour by detergent and soxhlet extraction, respectively, before biocomposites melt processing. The thermal, mechanical, structural, morphological, and flow properties of biocomposites with extracted BM flours were determined and compared to the properties of biocomposite with BM flour in natura. In addition, the influences of MAPE incorporation in the properties of each biocomposite were also studied, in order to understand their role in biocomposite compatibilization. The particle treatments resulted in biocomposites with lower tensile strength than biocomposites with BM in natura. Despite the low compatibility of MAPE with PHB, the addition of MAPE increased the tensile strength of the respective PHB biocomposite, reaching values of tensile strength similar or slightly higher than the PHBad-MAPE matrix. Therefore, MAPE acted as an effective additive for BM flour, probably, due to reactive processing with the starch polar surface groups. Since BM was abundantly and cheaply available, its use with PHB and MAPE resulted in biodegradable material with similar mechanical properties of neat PHB and concomitant reduction in cost.

As increasing environmental awareness drives the development of biocomposites, the reality is that these material are still far behind in terms of application. While modifications on biocomposites do improve its properties, they are often conducted individually per study and not altogether, which may limit its potential. To expand the marketability of biocomposites, this research covers the hybridization of natural and synthetic fibre, reinforcement of Sodium Hydroxide (NaOH) treated kenaf fibre, reinforcement of organomodified nanoclay, and the use of modified epoxy in the production of the biocomposite. The dispersion of nanoclay in modified epoxy was conducted via sonication while the selected composite fabrication method is hand lay-up. In the flexural test, treated kenaf composites increase by 52% in flexural strength and 46% in flexural modulus, while treated nanocomposites improve by 83% in impact absorbed energy. The rough surface of treated kenaf and fractured composite surface can be seen using a Field Emission Scanning Electron Microscope (FESEM), indicating high interfacial adhesion in treated kenaf composites. Spectroscopy investigation utilising Fourier Transform Infrared (FTIR) revealed that hemicellulose is easier to be removed with alkalization compared to lignin. X-Ray Diffraction Analysis (XRD) displays higher crystallinity in nanocomposites due to nanoclay.

In this study, pH-sensitive gelatin hydrogels reinforced with cellulose nanocrystals (CNCs) from rice husk were fabricated by introducing gamma irradiation to induce green cross-linking method hydrogels. The properties of the hydrogels were studied at varied CNCs and pH. The hydrogels were characterized by fourier-transform infrared (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), rheology, swelling studies, scanning electron microscopy (SEM), drug loading and release analysis, as well as cytotoxicity tests. The addition of CNC improved both the thermal and dynamic mechanical properties of the hydrogels. The hydrogels were sensitive to changes in pH, and the highest swelling degree was observed at pH 3. The optimum swelling performance was obtained with gelatin/4CNC hydrogels. SEM images revealed that incorporation of CNC content up to 4% improved the porosity of the hydrogels. The drug release analysis using riboflavin as a drug model showed that gelatin/4CNC hydrogels released more than 70% of riboflavin in 12 h. In addition, hydrogels showed non-cytotoxic properties, suggesting their potential application in drug delivery systems.

Waste coffee grounds, a biomaterial with high carbon content, have been suggested as a non-toxic organic flame retardant due to their high char forming and radical scavenging properties. Herein, investigations are conducted on the effects of waste coffee grounds, especially their concentration and particle size, on the mechanical properties, flame retardancy, toxic gas production of epoxy composites. Results reveal that reducing average size of the waste coffee grounds from 46 µm to 16 µm, using freeze-milling or filtering, can reduce peak heat release rate and total heat release of their epoxy composites by 52.0% and 33.7% respectively, exceeding the effectiveness of other bio-based flame retardants such as chitosan, lignin and seashell. More importantly, the fine coffee grounds can achieve the same performance as aluminium trihydrates, the most widely used non-bio flame retardant. Furthermore, the burning rates and emissions of toxic gas have also been greatly reduced, almost entirely suppressing the highly toxic NO2 gas. The findings provide new insights into the effect of particle size of waste coffee grounds on both the mechanical properties and flame retardancy performnance of epoxy composites.

The conversion of the fish and shrimp wastes to produce value-added products brings economic benefits and reduces the risk of environmental pollution. This study presents a facile method for preparing nano-hydroxyapatite/chitosan biocomposites (nHCB) for wastewater treatment and bacterial immobilization. It is a novelty that hydroxyapatite nanoparticles (nHA) and chitosan (CTS) were recovered from fishbone and shrimp shell sources. The prepared nHCBs showed a high porosity, and nHA particles were well distributed in the CTS matrix. Due to these unique properties as an adsorbent for removing dyes and Cu(II) ions from wastewater, nHCBs exhibited rapid adsorption, high capacity, and easy separation for cyclic use. The maximum sorption capacity were 44.05 mg/g (methylene orange), 84.89 mg/g (methylene blue), and 236.97 mg/g (Cu(II) ions). The findings suggest a great potential fabrication of low-cost bio-composites and their application for wastewater treatment.

This study presents rice husk silica-reinforced elastomer composites fabricated by wet compounding, exhibiting 10% higher dynamic friction coefficients than the reference composites made by conventional dry compounding. Depending on the fabrication method, the filler micro-dispersion was characterized to correlate the measured friction coefficients with the viscoelastic properties with respect to sliding velocity and substrate lubrication. The effect of viscoelastic properties of the elastomer composites on the adhesion and hysteresis friction coefficients was investigated based on the elastomer friction theory. It was found that the constructed friction master curves showed a reasonable correlation with the theory. This study demonstrates that the rice husk silica can be used as a reinforcing filler for sustainable tires. More importantly, the well-dispersed filler microstructures can ensure the higher friction coefficients of the elastomer composites on rough surfaces, improving the tire performances (e.g., wet traction, cornering, and acceleration) of the ever-growing electric vehicles and future mobility.

Distillers’ dried grains with soluble (DDGS), a by-product of the corn ethanol industry, has been shown to be useful as a filler in biocomposites. Work was done comparing the impacts of heat treatment (torrefaction, at 300°C) of DDGS and inclusion of compatibilizer on properties of a DDGS-filled biocomposite. The untreated or heat-treated DDGS (30 wt.%) was blended with poly (butylene succinate co butylene adipate) (PBSA) (70 wt.%), or PBSA offset with 3 wt.% maleic anhydride-grafted PBSA. As a result of the inclusion of DDGS, tensile and flexural modulus increased by 68% and 72%, respectively. The torrefaction heat treatment was shown to degrade the hemicellulosic content of the DDGS, which restored thermal stability lost with the addition of untreated DDGS. The improved compatibility with the addition of MA-g-PBSA resulted in improvement in heat deflection temperature , as well as tensile strength and flexural strengths, in both untreated and heat-treated samples. Notably, tensile and flexural strengths were further enhanced in the case of the untreated DDGS. Overall, this study shows how filler treatment combined with compatibilization in PBSA biocomposites impact material performance and their variability in specific properties when it comes to application options.

Owing to its low cost and sustainable nature, lignocellulosic biomass has been utilized for reinforcing polymers, but it is crucial to understand the impact of high-ash concentrations in biomass on composite strength and processing. Biomass is not only desirable for biofuel production but could also have a strong market, if high-ash biomass is acceptable, for biocomposites. In this work, natural fibers (switchgrass and corn stover) were used to reinforce polylactic acid (PLA) to produce biocomposites. Natural fibers were pretreated to obtain fibers that contain different percentages of ash. The mechanical properties (such as Young's modulus, tensile strength, failure strain, storage modulus) of corn stover/PLA composites remained largely unaffected by the ash concentration of the biomass fibers, despite the large range of ash contents (2.2–11.9 wt%). However, the tensile strengths of switchgrass/PLA composites were slightly negatively affected by the ash concentration of the switchgrass fibers (0.7–2.1 wt%). Both the switchgrass/PLA and the corn stover/PLA composites exhibited a high-enough tensile strength (49–57 MPa) and suitable complex viscosity (2.0−7.0 kPa·s at the frequency of 3.2 rad/s). They are expected to be 3D-printable through an extrusion-based additive manufacturing process.

The use of biopolymers for tissue engineering has recently gained attention due to the need for safer and highly compatible materials. Starch is one of the most used biopolymers for membrane preparation. However, incorporating other polymers into starch membranes introduces improvements, such as better thermal and mechanical resistance and increased water affinity, as we reported in our previous work. There are few reports in the literature on the biocompatibility of starch/chicken gelatin composites. We assessed the in vivo biocompatibility of the five composites (T1–T5) cassava starch/gelatin membranes with subdermal implantations in biomodels at 30, 60, and 90 days. The FT-IR spectroscopy analysis demonstrated the main functional groups for starch and chicken gelatin. At the same time, the thermal study exhibited an increase in thermal resistance for T3 and T4, with a remaining mass (~15 wt.%) at 800 °C. The microstructure analysis for the T2–T4 demonstrated evident roughness changes with porosity presence due to starch and gelatin mixture. The decrease in the starch content in the composites also decreased the gelatinization heats for T3 and T4 (195.67, 196.40 J/g, respectively). Finally, the implantation results demonstrated that the formulations exhibited differences in the degradation and resorption capacities according to the starch content, which is easily degraded by amylases. However, the histological results showed that the samples demonstrated almost complete reabsorption without a severe immune response, indicating a high in vivo biocompatibility. These results show that the cassava starch/chicken gelatin composites are promising membrane materials for tissue engineering applications. [ABSTRACT FROM AUTHOR]

Paunch is a fibrous solid residue consisting of partially digested feed from the stomachs of processed cattle. It is the largest untapped solid waste stream from animals at meat processing plants, and potentially a valuable source of fibres for the production of sustainable and potentially higher-value natural biocomposite materials. Paunch was obtained from the waste effluent of a red meat processing plant, and the fibre characteristics of the as-obtained material were studied and benchmarked against wood flour and ground buffel grass, with a view to evaluating the potential of paunch as a fibre for polymer composites. The ground paunch possessed a rough fibrous surface and fibre-like characteristics that were comparable to both wood flour and ground buffel grass, demonstrating their potential for use in composites. Without any pre-treatment or compatibilisation, composites of a representative biopolymer, poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and ground paunch were successfully produced for the first time via extrusion, with up to 50 wt% paunch content. Mechanical property analysis showed that, at 30 wt% content, PHBV/ground paunch composites yielded mechanical properties that were comparable to those of composites with ground buffel grass. [ABSTRACT FROM AUTHOR]

Cellulose fibers isolated from oil palm empty fruit bunches (OPEFB) have been studied as a potential reinforcement for polyvinyl alcohol (PVA) biocomposite. Analysis of variance (ANOVA) showed that all three parameters—hydrolysis temperature, time and acid concentration, as well as their interactions—significantly affected the yield of cellulose. Moving Least Squares (MLS) and Multivariable Power Least Squares (MPLS) models demonstrated good fitness. The model also proved that acid concentration was the dominant parameter, supported by the Fourier transform infrared spectroscopy (FTIR) analysis. Hydrolysis using 54% acid at 35 °C and 15 min achieved the highest cellulose yield of 80.72%. Cellulose-reinforced PVA biocomposite films demonstrated better mechanical strength, elongation at break, moisture barrier properties, thermal stability and poorer light transmission rate compared to neat PVA due to the high aspect ratio, crystallinity and good compatibility of cellulose fibers. These findings suggested the potential of cellulose fibers-reinforced PVA biocomposite film as water-soluble detergent capsules. [ABSTRACT FROM AUTHOR]

The goal of this study was to fabricate bioactive cell‐laden biocomposites supplemented with bone‐derived decellularized extracellular matrix (dECM) with calcium phosphate ceramic, and to assess the effect of the biocomponents on the osteogenic and odontogenic differentiation of human dental pulp stem cells (hDPSCs). By evaluating the rheological properties and selecting printing parameters, mechanically stable cell‐laden 3D biocomposites with high initial cell‐viability (>90%) and reasonable printability (≈0.9) were manufactured. The cytotoxicity of the biocomposites was evaluated via MTT assay and nuclei/F‐actin fluorescent analyses, while the osteo/odontogenic differentiation of the hDPSCs was assessed using histological and immunofluorescent analyses and various gene expressions. Alkaline phosphate activity and alizarin red staining results indicate that the dECM‐based biocomposites exhibit significantly higher osteogenic activities, including calcification, compared to the collagen‐based biocomposites. Furthermore, immunofluorescence images and gene expressions demonstrated upregulation of dentin matrix acidic phosphoprotein‐1 and dentin sialophosphoprotein in the dECM‐based biocomposites, indicating acceleration of the odontogenic differentiation of hDPSCs in the printed biocomposites. The hDPSC‐laden biocomposite was implanted into the subcutaneous region of mice, and the biocomposite afforded clear induction of osteo/odontogenic ectopic hard tissue formation 8 weeks post‐transplantation. From these results, we suggest that the hDPSC‐laden biocomposite is a promising biomaterial for dental tissue engineering. [ABSTRACT FROM AUTHOR]

Biocomposite boards (BcBs) composed of hemp shives and corn starch are known as thermal insulating or structural building materials. Therefore, they must be stable during exploitation. However, BcBs are exposed to microorganisms present in the environment, and it is of great interest to investigate the biodegradation behaviour of these materials. This work identified microorganisms growing on BcBs that contain either Flovan CGN or expandable graphite as flame retardants and selected fungi such as Rhizopus oryzae and Aspergillus fumigatus to test the way they affect the materials of interest. For this purpose, the enzymatic activity of cellulases and amylases produced by these organisms were determined. In addition, the apparent density as well as compressive strength of the affected boards were evaluated. The results showed that apparent density and compressive strength deteriorated in BcB composition with the Flovan CGN flame retardant. At the same time, the level of deterioration was lower when the expandable graphite was used, suggesting that it also acts as an antimicrobial agent. A scanning electronic microscopy analysis was employed to monitor the growth of microorganisms in the BcBs. Such analysis demonstrated that, regardless of BcB composition, fungi easily penetrate into the middle layers of the material. [ABSTRACT FROM AUTHOR]