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Screw pine root fibers are engineering fibers that have yet to be explored in terms of its chemistry with bio‐resin in biodegradable composites to replace nonbiodegradable thermoplastics used in packaging, automobiles, furniture, and industrial sectors. Screw pine root fibers are reinforced with soy, poly(vinyl alcohol), and soy‐poly(vinyl alcohol) resin systems in this work to create a variety of composites. Composites demonstrated highest amount of tensile strength at around 39.7 MPa, 37.6 MPa of flexural property, along with an impact strength around 12.4 kJ/m2. The thermal solidity of the optimized material was determined to be 235°C. After 24 hours of immersion, the composite had the lowest water absorption of 18.4%. All composites were shown to be biodegradable, losing about 54.2%–72.9% of their original mass after 60 days in soil burial. Unique characteristics such as the use of low‐cost agricultural materials, water‐based resin, stable composite, and properties such as moderately strong, safe disposal after service periods make these manufactured composites market feasible as consumer‐friendly/ecofriendly green products. Highlights: Screw pine root fibers were extracted from waste roots and used as reinforcement.The tensile strength of the composite was achieved as 39.7 MPa.The water absorption of hybrid composite was found 30.8% after 24 h.After 60 days under soil burial, composite lost 67.5% of its original weightDeveloped composites can be good alternant for nondegradable thermoplastic. [ABSTRACT FROM AUTHOR]

Jarosite, an industrial waste, has the potential to be used as an alternative filler in biocomposites used as packaging material and can replace nondegradable thermoplastic. Such a novel approach of waste management strategy has not been studied till date. In this research work, different weight percentages of jarosite were mixed with poly(vinyl alcohol) (PVA) to fabricate polymer composites with better physico‐chemical, thermal, tensile, and biodegradation properties. The data indicate that a low concentration of jarosite (3 wt.%) improved the tensile strength by 198.7% and the composite showed higher thermal stability by 6.3% than that of the neat PVA. X‐ray diffractogram and transmission electron microscopic analysis revealed a strong interaction between PVA and jarosite. Interestingly, the addition of jarosite reduced the water absorption capacity and thickness swelling of the PVA composite by 58% and 54.7%, respectively. Jarosite‐incorporated composites showed lesser degradation potential (64%) than the control composites (84%) after 60 days under soil burial conditions, indicating that PVA‐jarosite composites have a higher shelf‐life, which is needed for packaging materials. These composites can also be good alternant for thermoplastic used in preparation of cuboid, sealing, and decorative materials. Also, this would be a novel sustainable approach for managing/reducing jarosite waste. Highlights: Jarosite was reinforced with PVA to fabricate biocomposites.The maximum tensile strength of the composite was achieved as 45.4 MPa.The thermal stability of mechanically optimized composite is found at 320°C.After 60 days under soil burial, the composite lost 64.8% of its original weight.Developed composites can be good alternant for nondegradable thermoplastic. [ABSTRACT FROM AUTHOR]

A novel, promising biocomposite was synthesized through the free radical polymerization method using methyl methacrylate (MMA), acrylic acid (AA), and hydroxyapatite derived from oyster shells (Os‐HA). Fourier transform infrared spectroscopy (FTIR) peaks indicate the conjugation of Os‐HA in the biocomposite. From the TGA analysis, it was observed that a weight loss of nearly 2% is achieved at 210°C, up to 15% at 210 to 420°C, and up to 95% at 420 to 580°C. The SEM image shows the uniform dispersion of the Os‐HA particles and strong interaction with the copolymer matrix. The broad spectrum at 2θ = 14.6° in XRD analysis indicates the amorphous nature of poly(MMA‐co‐AA)/Os‐HA. The higher inhibition zone of the biocomposite is observed at 125 μL against E. coli bacteria. The maximum water absorption is observed at 15 wt% of Os‐HA. The young's modulus gradually increases, while the impact strength decreases up to 20 wt% of Os‐HA. The artificial neural network (ANN) model has been used to assess the optimum values of impact strength, tensile strength, and Young's modulus of the biocomposite material. The correlation factor (R = 0.998) of the ANN model data indicates greater accuracy of the experimental result. [ABSTRACT FROM AUTHOR]

In order to solve the problems of dust, low mixing efficiency, and poor quality stability in dry mixing and continuous mixing, this study combined the flocculation extrusion technology with continuous mixing technology of carbon black/additives/natural rubber composites. The flocculation of latex was achieved by carbon black itself and the shearing of the twin screw. The continuous mixing was carried out in a double‐rotor continuous mixer, which was composed of functional elements such as the exhaust section and extrusion section. The results showed that the technology promoted the formation of the filler‐rubber network, the sensitivity of viscosity to temperature was weakened, and the rubber was closer to a Newtonian fluid, with less extrusion swell phenomenon and no obvious spiral distortion. Compared with the dry mixing, the tensile strength, rebound rate, and abrasion resistance of the rubber composites prepared by this technology were increased by 11%, 31%, and 9%, respectively, providing theoretical and technical guidance for the green production and continuous production of high‐performance natural rubber composites. Highlights: The process is achieved by a twin‐screw extruder and a twin‐rotor continuous mixer.The process promotes the formation of the filler‐rubber network.The sensitivity of viscosity to temperature is weakened, with no spiral distortion.The tensile strength, rebound rate, and abrasion resistance are increased by 11%, 31%, and 9%. [ABSTRACT FROM AUTHOR]

Natural fibers are one of the most attractive materials in biocomposites due to their potential for sustainability. This study aims to prepare sustainable composite materials using fibers from Sansevieria trifasciata (snake plant) and to investigate their mechanical, morphological, and water absorption properties. The composite was prepared with epoxy resin through a manual hand lay‐up process, maintaining standard parameters with changeable reinforcement (10%, 20%, and 30%). The mechanical properties (tensile, impact, and flexural strength), Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), and water absorbency of the composites were evaluated. The result showed that the tensile strength, flexural strength, and impact resistance of the composites are 6.99 MPa, 10.77 MPa, and 14 J, respectively, for 30% fiber components, which are significantly higher than other composite materials. The SEM analysis showed a strong interfacial bond between the snake plant fiber and the epoxy resin. The FTIR analysis revealed a reduction in hemicellulose and lignin and an improvement in the interfacial adhesion between snake plant fiber and epoxy resin. The composites also demonstrated time‐dependent increases in water absorption, with the sample containing 30% fiber components showing the best absorbency performance at 0.88%. Highlights: A study is being conducted on the effective and sustainable use of biowaste.The composite materials loaded with 30% fibers had significantly high tensile strength, flexural strength, and impact resistance.The SEM analysis of snake plant fiber‐reinforced polymer composite showed a strong interfacial bond between fiber and epoxy resin.The FTIR analysis of the composite revealed the reduction of hemicellulose and lignin.The use of non‐renewable materials is reduced, and eco‐friendliness is promoted. [ABSTRACT FROM AUTHOR]

Purpose: Biodegradable interference screws (IFS) can be manufactured from different biomaterials. Magnesium was previously shown to possess osteoinductive properties, making it a promising material to promote graft-bone healing in anterior cruciate ligament reconstruction (ACLR). The purpose of this study was to compare IFS made from magnesium to a contemporary biocomposite IFS. Methods: In a porcine model of ACL reconstruction, deep porcine flexor tendons were trimmed to a diameter of 8 mm, sutured in Krackow technique, and fixed with either 8 × 30 mm biocomposite IFS (Bc-IFS) or 8 × 30 mm magnesium IFS (Mg-IFS) in an 8 mm diameter bone tunnel in porcine tibiae. Cyclic loading for 1000 cycles from 0 to 250 N was applied, followed by load to failure testing. Elongation, load to failure and stiffness of the tested constructs was determined. Results: After 1000 cycles at 250 N, elongation was 4.8 mm ± 1.5 in the Bc-IFS group, and 4.9 mm ± 1.5 in the Mg-IFS group. Load to failure was 649.5 N ± 174.3 in the Bc-IFS group, and 683.8 N ± 116.5 in the Mg-IFS group. Stiffness was 125.3 N/mm ± 21.9 in the Bc-IFS group, and 122.5 N/mm ± 20.3 in the Mg-IFS group. No significant differences regarding elongation, load to failure and stiffness between Bc-IFS and Mg-IFS were observed. Conclusion: Magnesium IFS show comparable biomechanical primary stability in comparison to biocomposite IFS and may therefore be an alternative to contemporary biodegradable IFS. [ABSTRACT FROM AUTHOR]

Spearing mantis shrimps are aggressive crustaceans using specialized appendages with sharp spikes to capture fishes with fast movement. Each spike is a biological tool that has to combine high toughness, as required by the initial impact with the victim, with high stiffness and strength, to ensure sufficient penetration while avoid breaking.We performed a multimodal analysis to uncover the design strategies of this harpoon based on chitin. We found that the spike is a slightly hooked hollow beam with the outer surface decorated by serrations and grooves to enhance cutting and interlocking. The cuticle of the spike resembles a multilayer composite: An outer heavily mineralized, stiff, and hard region (with average indentation modulus and hardness of 68 and 3 GPa), providing high resistance to contact stresses, is combined with a less mineralized region, which occupies a large fraction of the cuticle (up to 50%) and features parallel fibers oriented longitudinally, enhancing stiffness and strength. A central finding of our work is the presence of a tiny interphase (less than 10 μm in width) based on helical fibers and showing a spatial modulation in mechanical properties, which has the critical task to integrate the stiff but brittle outer layer with the more compliant highly anisotropic parallel-fiber region.We highlighted the remarkable ability of this helicoidal region to stop nanoindentation-induced cracks.Using three-dimensional multimaterial printing to prototype spike-inspired composites, we showed how the observed construction principles can not only hamper damage propagation between highly dissimilar layers (resulting in composites with the helical interphase absorbing 50% more energy than without it) but can also enhance resistance to puncture (25% [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 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]

The sustainable development of engineering biocomposites has been limited due to a lack of bio‐based monomers combining favorable processing with high performance. Here, the authors report a novel and fully bio‐based transparent wood biocomposite based on green synthesis of a new limonene acrylate monomer from renewable resources. The monomer is impregnated and readily polymerized in a delignified, succinylated wood substrate to form optically transparent biocomposites. The chemical structure of the limonene acrylate enables diffusion into the cell wall, and the polymer phase is both refractive index‐matched and covalently linked to the wood substrate. This results in nanostructured biocomposites combining an excellent optical transmittance of 90% at 1.2 mm thickness and a remarkably low haze of 30%, with a high mechanical performance (strength 174 MPa, Young's modulus 17 GPa). Bio‐based transparent wood holds great potential towards the development of sustainable wood nanotechnologies for structural applications, where transparency and mechanical performance are combined. [ABSTRACT FROM AUTHOR]

The study presents the results of the study on porous composite biomaterials obtained using lyophilization method based on polymer solutions: chitosan solution, sodium alginate solution, or polylactide solution, and ZnO-doped bioglass from CaO-SiO2-P2O5 system. The properties of zinc ions were used, which have bactericidal, immune-stimulating, and tissue-regenerating functions in the organism. The effects of the polymer type, granulation, and bioglass amount, as well as the amount of solvent on composite microstructure, were studied. SEM- EDS technique was used to visualize and describe the surface results occurring after incubation of composite in the Simulated Body Fluid ( SBF). The selected method of preparation, used substrates, and the process conditions resulted in porous composites of the open, connected pore structure. It was proved that composite microstructure may be controlled by the appropriately selected amount of bioglass in relation to the polymer and its appropriate grain sizes. The morphology of the obtained composites is also affected by the amount of the solvent in lyophilizated dispersions. It was proved that bioactivity in composite material is induced by bioglass because after SBF incubation the surface layer is enriched with Ca and P, what may lead to a gradual formation of apatite layer. The obtained results enabled selection of the composites for further in vitro studies concerning cytotoxicity and antibacterial activity. [ABSTRACT FROM AUTHOR]

Bioceramics have been extensively used for various medical applications including hip and knee prostheses, tissue engineering scaffolds, and dental implants. Bioceramics, particularly bioglass, are desired because of their bioactivity but are often limited by their inherent brittleness. To compensate, composites have been formed to obtain unique properties where both bioactivity and mechanical integrity can be achieved. Mullite-reinforced titania-bioglass (TiO2- BG) composites were therefore deposited using plasma spraying technique. The microstructure of the coating materials were analyzed for their morphology and microstructure using scanning electron microscopy/energy dispersive spectrometry. Mechanical properties of the coatings were tested using three-point bend test, indentation test, and pin-on-disk wear test to determine their fracture strength, fracture toughness, and wear resistance, respectively. The addition of mullite fibers improved the fracture strength and wear resistance of TiO2- BG composites while having minimal effect on fracture toughness. After the addition of mullite, failure mode was bimodal, failing intergranularly and by fiber pull-out. Although mullite fibers have not been particularly used for medical applications, fiber reinforcement has shown efficacy in mechanically reinforcing composites of various medical applications. [ABSTRACT FROM AUTHOR]