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This study investigates the hygrothermal aging effect on the tensile and impact behavior of flax/PLA biocomposites. Specimens underwent up to four weeks of conditioning at 40°C in a climate chamber with water. Analysis covered porosity, moisture diffusibility, and transversal microstructure, enabling assessment of tensile strength, tensile modulus, and impact performance in relation to moisture uptake and fiber orientation. The study of tensile properties revealed that at approximately 12% moisture content, stiffness and yield stress decrease, while strength remains constant. Moisture diffusivity is higher in warp and weft yarn directions than the out‐of‐plane direction. Tensile testing at environmental equilibrium moisture reveals greater stiffness in the weft direction, correlated with lower crimp percentage and yarn angle. The main contribution of the paper is the study of the influence of moisture on the impact behavior, the results show that energy absorption capability of flax/PLA biocomposite increases with moisture content. Highlights: Fully biodegradable composite material by heat‐compression molding subjected to hygrothermal aging conditions for up to four weeks.The moisture diffusivity in both the warp and weft yarn directions registered higher values in comparison to the out‐of‐plane direction.Tensile testing at environmental equilibrium moisture revealed that the stiffness in the weft direction presented higher values.At 12% of moisture uptake, the stiffness and yield stress reached their lowest values, while strength remained constant.However, the low‐velocity impact properties of the composites exhibited improvement with moisture. [ABSTRACT FROM AUTHOR]

In the evolving field of bioproducts, materials that synergize sustainability with functionality are of paramount importance. Mycelium composites, derived from intricate networks of fungal filaments, are gaining traction as innovative bioproducts that offer a compelling blend of eco‐friendliness, renewability, and adaptability. As the quest intensifies for alternatives that can mitigate the environmental toll of conventional products, mycelium‐based solutions are emerging as beacons on the sustainable bioproducts horizon. Their transition from niche innovations to mainstream applications depends on their ability to overcome a series of fabrication challenges. This review paper investigates the critical challenges faced in the fabrication of mycelium composite. It examines rigorously some essential factors leading to fabrication failure, such as contamination, inconsistent growth, insufficient moisture, inappropriate pH, and improper substrate preparation. The review offers a comprehensive analysis of each factor influencing mycelium growth and the resulting composite properties, with an emphasis on preventative and mitigating strategies. Through an in‐depth exploration of case studies detailing unsuccessful mycelium composite fabrication, the significance of understanding these failure factors is emphasized. The paper culminates in a forward‐thinking discourse on potential strategies for refining fabrication processes, and identifies promising research areas poised to enhance both the success rate and overall efficiency of mycelium composite production. [ABSTRACT FROM AUTHOR]

Manufacturing PHBV biocomposites with spent coffee ground (SCG) is an eco‐friendly approach of repurposing waste materials to improve sustainability. Although, as shown previously, pretreatments of SCG can improve its interaction with PHBV to obtain enhanced properties, the chemical or biological treatment could be time‐consuming, costly, and environmentally harmful. Therefore, this study developed a method of manufacturing PHBV/SCG biocomposites via a simple and industrially viable reactive extrusion method requiring no SCG pretreatment. The present work aims at investigating the impact of untreated SCG combined with different processing additives (peroxide, coagent, and chain extender) on the morphological, thermal, mechanical, and water absorption properties of PHBV‐based biocomposites. Overall, the introduction of the untreated SCG (10–30 wt.%, without processing additives) decreased the crystallinity (by 3.8%–6.8%), degradation temperature (Tpeak, by 6.2%–8.2%) and tensile strain (by 33%–43%) of PHBV. SCG addition had no significant effect on PHBV tensile strength or Young's modulus. However, the presence of processing additives decreased the melting temperature (by up to 4.5°C), crystallinity (by up to 8.4%) and Young's modulus (by up to 17%) and increased the degradation temperature (Tpeak, by up to 12.5°C) of the PHBV/SCG biocomposites (10% wt.% SCG). Lastly, SCG addition improved water absorption ability of PHBV by up to 250%, while the addition of peroxide further improved the water absorption ability by approximate 320%. The PHBV/SCG developed in this study have good renewability and biodegradability, improved water absorption property, reduced cost and acceptable mechanical properties. They are promising in applications where biodegradability is favorable and high mechanical performance is not required such as plant pots and containers. [ABSTRACT FROM AUTHOR]

Highlights Starch‐based biocomposites exhibit great potential as an alternative to fossil‐based materials. This work focused on investigating the properties of the starch‐based biocomposite reinforced by cellulose nanofibers derived from sugarcane bagasse (SCB). The sodium hydroxide (NaOH) concentration was varied from 4%, 8%, and 12% wt/vol for the SCB extraction process. The obtained nanofibers, respectively called SCBNF4, SCBNF8, and SCBNF12, were characterized by various techniques prior to being incorporated into modified starch (MS). The effects of the type and amount of SCBNF on the mechanical properties, thermal behavior, optical transparency, and moisture absorption of the biocomposite films were examined. All SCBNF samples had a cellulose type I structure with a diameter on the nanometer scale, regardless of the NaOH concentration. The SCBNF's diameter decreased, whereas the crystallinity index increased with increasing NaOH concentration. When incorporated into MS, the higher SCBNF loading resulted in enhancements of mechanical properties and resistance to moisture absorption with the sacrifice of optical transparency. The biocomposite filled with SCBNF12 exhibited better overall performance at a certain filler loading due to the greater filler‐polymer interaction. The benefits of greater strength, light weight, and eco‐friendliness of the developed biocomposites make them suitable for many applications, including packaging. Diameter and crystallinity index of SCBNF were governed by NaOH concentration. Adding SCBNF to MS greatly improved the biocomposite's mechanical properties. SCBNF12 showed the highest biocomposite's overall performance. The maximum strength was achieved at 1 phr of SCBNFs. The addition of SCBNFs reduced water and moisture absorption. [ABSTRACT FROM AUTHOR]

Polyethylene (PE), a highly prevalent non‐biodegradable polymer in the field of plastics, presents a waste management issue. To alleviate this issue, bio‐based PE (bio‐PE), derived from renewable resources like corn and sugarcane, offers an environmentally friendly alternative. This review discusses various production methods of bio‐PE, including fermentation, gasification, and catalytic conversion of biomass. Interestingly, the bio‐PE production volumes and market are expanding due to the growing environmental concerns and regulatory pressures. Additionally, the production of PE and bio‐PE biocomposites using agricultural waste as filler materials, highlights the growing demand for sustainable alternatives to conventional plastics. According to previous studies, addition of ≈50% defibrillated corn and abaca fibers into bio‐PE matrix and a compatibilizer, results in the highest Young's modulus of 4.61 and 5.81 GPa, respectively. These biocomposites have potential applications in automotive, building construction, and furniture industries. Moreover, the advancement made in abiotic and biotic degradation of PE and PE biocomposites is elucidated to address their environmental impacts. Finally, the paper concludes with insights into the opportunities, challenges, and future perspectives in the sustainable production and utilization of PE and bio‐PE biocomposites. In summary, production of PE and bio‐PE biocomposites can contribute to a cleaner and sustainable future. [ABSTRACT FROM AUTHOR]

Highlights The study presents the ideal distribution of graphene nanoplatelets (GNP) within the thermoplastic starch (TPS) matrix significantly elevated the thermal and electrical conductivities, as well as the electrochemical efficiency of the biocomposites. Additionally, the incorporation of GNP resulted in an increased thermal stability for the TPS, as indicated by the elevated temperatures required for maximum degradation. The biocomposites exhibited a self‐aligned layered structure, creating conductive pathways and enhancing electron conduction. An electrical conductivity increased as the concentration of GNP increased, with the highest conductivity observed on the top and bottom surface with the value of 4.23 × 10−7 S/m and 3.92 × 10−6 S/m when 12 wt% of GNP was added. The presence of hydroxyl groups in TPS facilitated the formation of hydrogen bonds with GNP, preventing GNP from stacking and forming a more uniform conductive network within the film. The addition of 15 wt% GNP also improved the capacitive performance of the TPS matrix, as evidenced by higher current responses and larger quasi‐rectangular areas in the cyclic voltammetry curves compared to neat TPS. The Nyquist plots which are illustrated impedance data showed that the TPS film with 12 wt% GNP exhibits the smallest semicircle, indicating the highest conductivity which is suggested that GNP improves charge transfer compared to pure TPS. Optimal dispersion of GNP enhanced the biocomposite's properties. The electrical conductivity increases with the GNP content until 12 wt%. TPS/GNP self‐aligned layered improved conduction and capacitive behavior. GNP improved thermal stability by restricting polymer chain movement. Electrochemical impedance shows improved properties of TPS/GNP. [ABSTRACT FROM AUTHOR]

This study explores the utilization of Spent Coffee Grounds (SCG), a residual product of the coffee industry, as a microfiller reinforcement in Poly‐3‐hydroxybutyrate‐co‐3‐hydroxyvalerate (PHBV) biopolymer composites at varying concentrations (1%, 3%, 5%, and 7%). Melt compounding via a twin‐screw extruder and subsequent compression molding were employed in the fabrication process. The SCG microfiller, with particle diameters ranging from 1.11 to 1.28 μm, exhibited a significant negative charge (zeta potential: −20 mV). Hydrophobicity increased up to 5% filler concentration, as indicated by higher water contact angles, but diminished at highest concentration likelihood of agglomeration of the spent coffee grounds within the biopolymer matrix. The addition of SCG enhanced overall mechanical properties, particularly at a 5% filler concentration. Field Emission Scanning Electron Microscopy (FE‐SEM) and Atomic Force Microscopy (AFM) confirmed the successful incorporation of SCG microfiller, improving structural characteristics. Schematic drawings illustrated the interphase bonding of microfiller and matrix. However, properties diminished at the highest filler content (7%) due to coffee grounds' agglomeration. Despite this, SCG incorporation enhanced functional properties, making the biopolymer composite a promising material for sustainable packaging and various applications. Highlights: Enhancement of properties of spent coffee grounds in PHBV biocomposites.Characterization of Biocomposites for multifunctional properties.Fracture and 2D analysis of the tensile fractured surface of biocomposites.A promising material for sustainable and biodegradable packaging. [ABSTRACT FROM AUTHOR]

Highlights Development of biocomposites is becoming a necessity due to environmental concerns. Polylactide is a matrix of choice, regarding its bio‐sourced and compostable nature along with its mechanical properties. In this study, poly(L‐lactide)/flax biocomposites were produced using thermoplastic resin transfer molding (TP‐RTM) in one step process from the monomer, affording sustainable and fully compostable composite materials. The polymerization of L‐lactide (L‐LA) monomer was promoted by tin octoate, affording poly(L‐lactide) (PLLA) matrices displaying monomer conversions superior to 96% and mass‐average molar masses above 140,000 g/mol. Flax fibers were used as received without any functionalization which is usually conducted to prevent the hydroxyl groups to conduct side reactions. Mechanical testing revealed bending modulus of 9.3 GPa and bending strength of 177 MPa comparable to existing literature values for PLLA/flax composites produced by other techniques. Digital microscopy analysis provided insights into impregnation quality and void characterization within the composites. In addition, the durability of these biocomposites was also evaluated via accelerated aging tests. PLLA/flax biocomposites were produced by TP‐RTM for the first time. In situ polymerization of the PLLA matrix associated with non‐functionalized flax fabrics was conducted. Bending properties were found in line with those of PLLA/flax composites produced by compression molding. Aging tests under UV at 50°C of PLLA/flax biocomposites were conducted. [ABSTRACT FROM AUTHOR]

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]

Synthetic polymers have made advances in terms of their flexibility and other properties but a major problem still exists when it comes to their poor biodegradability and lack of conservation. To overcome this problem, the biocomposites are widely used for wide range of applications. Crop residues (CRs) from agriculture can be utilized to make items like biodegradable components; however, they are hard to recycle or dispose of. The aim is to use corn cob ash (CCA), which is generated by calcination of corn cob (CC) in a pectin matrix to create a biocomposites. The Fourier transform infrared (FTIR), X‐ray diffraction (XRD), and energy‐dispersive X‐ray analysis (EDX) show the major compounds present in the CCA are silica, potassium, calcium, and many other inorganic compounds. In this research, a solution casting method is used to fabricate pectin/CC biocomposite films. By increasing the content of the CCA, the moisture content will decrease, contact angle and hardness properties are increased. However, increasing CCA content promotes the color change of pectin/CC biocomposite films and water absorption increases. The composite films are analyzed for biodegradation study. The FTIR, morphological, mechanical property, XRD, and thermogravimetric analysis (TGA) studies are used to evaluate the biocomposite films. [ABSTRACT FROM AUTHOR]

To enhance the adhesion at the interface between polylactic acid (PLA) and local luffa fibers (LFs), and improve the properties of these fully biodegradable biocomposites, 10% of maleic anhydride grafted Styrene–ethylene–butylene–styrene (SEBS‐g‐MA) is added to act concomitantly as compatibilizer and toughening agent. PLA/LF and PLA/SEBS‐g‐MA/LF biocomposite materials were manufactured by melt mixing and then characterized by torque assessment, Fourier transform‐infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and Izod impact test. In accordance with SEM observation, FTIR analysis and torque measurements, the interfacial bonding coupling the PLA chains to LF via SEBS backbones resulted from the chemical reactions between the functional groups of the composites components. This contributed in increasing notably the impact resistance and the thermal stability compared with the biocomposites without SEBS‐g‐MA. In addition, the improvement of the impact strength might be induced by the flexible ethylene‐butylene blocks, which act as impact absorbers due to their rubber‐like behavior. [ABSTRACT FROM AUTHOR]

The enhancement of the mechanical and thermal characteristics of 3D printed polylactic acid (PLA) composites reinforced by coir fiber powder (CFP) has been investigated by varying the weight percentage (wt%) of the reinforcement and annealing process. CFP/PLA composite filaments with CFP compositions of 0.1, 0.3, and 0.5 wt% were fabricated. These filaments were used to print CFP/PLA test specimens. The specimens were annealed at 90°C for 120 min in a hot air oven followed by cooling at room temperature. Mechanical, morphological, crystalline, and thermal characterizations were conducted on these specimens. The tensile and flexural strength of neat PLA were observed as 49.7 and 82.4 MPa which decreased by 6.4% and 8.13% respectively for printed composite specimens with 0.5 wt% CFP as reinforcement material. On the other hand, the annealed CFP/PLA composite specimen, with 0.1 wt% CFP as a reinforcement material, demonstrated higher tensile and flexural strength. Specifically, it exhibited a maximum tensile strength of 56.4 MPa and a maximum flexural strength of 92.9 MPa, which are 13.5% and 12.7% higher, respectively, than neat PLA. These strengths are 15.5% and 16.7% higher, respectively, than those of the unannealed CFP/PLA composite specimen with the same wt% of CFP reinforcement. The annealing process increased the crystallinity of composites by enhancing the crystallinity index (63%) and crystalline size (6.7 nm). The high thermal stability of composites (with a glass transition temperature of 256°C) makes them suitable for applications in food and medical packaging. Highlights: Enhancement of thermo‐mechanical characteristics of 3D printed bio‐composites.Annealing process improved mechanical features of 3D printed bio‐composites.Annealed composite with 0.1 wt% as reinforcement demonstrated better properties.SEM and XRD studies confirmed failure mechanisms and crystalline structure.Thermal and mechanical assets favor its utilization in food wrapping applications. [ABSTRACT FROM AUTHOR]

Great environmental and economic benefits can be achieved by utilizing the agricultural residue corn stover (CS) to prepare the biodegradable poly(butylene adipate‐co‐terephthalate) (PBAT) composites. However, CS contains polarized hydroxyl groups from its main component cellulose, thus leading to its poor wetting by hydrophobic PBAT. It is of great significance to promote the compatibility between CS and PBAT for the improvement of interfacial interactions and composite performance, but the compatibilizer modified CS/PBAT biocomposites have been rarely mentioned until now. In this study, polyethylene glycol (PEG), glycidyl methacylate (GMA), and ethylene vinyl alcohol copolymer (EVOH) were chosen to investigate the compatibilizer effect on the morphology, microstructure, thermal properties, mechanical strength, and water absorption capacity of the biodegradable CS/PBAT composites. The results reveal that the incorporated compatibilizers obviously improve the interface adhesion between CS and PBAT by reducing the hydrophilicity of CS surface. The enhanced interfacial bonding interactions effectively promote the crystallinity and mechanical strength of the CS/PBAT composites, but the initial degradation temperature and hydrophilicity of compatibilizers themselves also remarkably influence the composites' thermostability and water absorption. Highlights: The agricultural residue corn stover (CS) was used to reinforce PBAT.Effects of three different compatibilizers on the composites were studied.Compatibilizer improves the interface adhesion between CS and PBAT.Compatibilizer promotes crystallinity and mechanical strength of composites.The stability and hydrophilicity of compatibilizer affect those of composite. [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 recent years, there has been a growing concern to counter environmental pollution, and as a result the development of biodegradable materials in various applications has become a major focus. This study aimed to fabricate a biodegradable composite by utilizing discarded hair keratin from beamhouse processing in leather production along with incorporating graphene oxide (GO) to reduce pollution. The composite was prepared using a simple solution mixing method, where the amino functional group of keratin and the carboxyl group of GO were covalently bonded under a redox system. Various analyses, including UV–visible spectroscopy, Fourier transform infrared spectroscopy, Raman spectroscopy, SEM, biodegradability and oxygen gas transmittance rate, were carried out to evaluate the composite's structure and performance. The results demonstrated that GO was successfully integrated into the keratin matrix, with uniform dispersion of GO observed instead of agglomeration. The composite with the optimum ratio exhibited a 173.98% increase in tensile strength and a 33.52% decrease in elongation as well as improved thermal and biodegradation properties compared to pure keratin. Furthermore, the composite displayed significantly better gas barrier properties (39%) than pure keratin, which can be attributed to the reduction of intermolecular gaps through the composite's strong bonding. Hence, the keratin‐GO composite is a cost‐effective and biodegradable solution to waste materials, with potential use as a packaging material. © 2023 Society of Chemical Industry. [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]

In recent years, the "new car smell" has been linked to materials off‐gassing toxic volatile organic compounds (VOCs) within the chamber of vehicles. Previous studies collected air samples directly from the vehicle chamber and analyzed them using gas chromatography–mass spectrometry (GC–MS). However, there is a lack of data regarding which materials are responsible for each compound and the resulting concentrations. This preliminary research was focused on analysis of VOC emissions emitted from basalt fiber and hemp hurd‐reinforced polypropylene (PP) panels, glass fiber reinforced PP panels, and PP panels intended for interior automotive applications such as dashboards and door panels. The panels were subjected to various temperatures and UV radiation that may be experienced within a vehicle. Results showed increasing concentrations as temperature increased, and a reduction in off‐gassing in the presence of UV radiation. The major compounds detected were acetaldehyde (<41 μg/m3), acetone (<29 μg/m3), and various alkanes (<6786 μg/m3). Overall, the concentrations detected from all panels were below the suggested standards and limitations. [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]

The use of banana pseudo stems is currently acknowledged as a sustainable raw material that piqued researchers' interest because of their high cellulose content, and good to moderate tensile strength. In order to develop various batches of biodegradable composite, peduncle fibers from waste banana peduncles were isolated and then reinforced after mild alkali treatment with biodegradable soy resin, phenol‐formaldehyde (resole), and soy‐resole resins via thermoforming (compressing) method. Peduncle fiber reinforced soy‐resole composite exhibited maximum tensile strength of 43.5 MPa and flexural strength of 36.2 MPa as a result of strong interaction/bonding between functional groups of the two biomaterials used here. All composites were put through a water sorption test, which showed that they are fairly hydrophobic by nature since after 24 h, they absorbed 10.2%–28.2% of water. These composites proved to be both eco‐friendly and biodegradable, since they broke down easily in the soil after 60 days and all of the composites lost about 70% of their original weight. These composites are anticipated to be used as an alternative to environment threatening plastic in indoor furniture, packaging, and computer cabinets. Highlights: Banana peduncle fiber was extracted from waste peduncle and used as reinforcer.The tensile strength of the composite was achieved as 43.5 MPa.The water absorption of composite was found 10.2% only after 24 h.After 60 days under soil burial, composite lost 70.8% of its original weight.Developed composites can be good alternant for non‐biodegradable thermoplastic. [ABSTRACT FROM AUTHOR]

This research was carried out to figure out the effect of chemical treatments of hazelnut shell powders (HSPs) on the elastic properties, ultrasonic wave velocities, and damping properties of bio‐based epoxy resin (BER) biocomposites. Natural hazelnut shells (HSs) were chemically treated using sodium hydroxide (NaOH), and acetic anhydride (AA). Then, HSs that were chemically treated with NaOH and AA, and HSs that were not subjected to chemical treatment were ground to obtain HSPs. The treated HSPs (HSP‐NaOH and HSP‐AA), and untreated HSPs were contributed to the neat BER in varied compositions such as 10–50 wt% to obtain the BER/HSP, BER/HSP‐NaOH, and BER/HSP‐AA biocomposites. The effect of untreated, and treated HSP ratios on the density, ultrasonic wave velocities, Young's modulus, Bulk modulus, Shear modulus, Poisson ratio, microhardness, and damping characteristics (attenuation coefficient, loss tangent and quality factor) of the novel HSP‐based biocomposites, was investigated by the ultrasonic pulse‐echo overlap method (PEOM). A significant increase in the density, ultrasonic wave velocities, and elastic modulus values of the biocomposites was seen compared to the neat BER. Based on the obtained elastic modulus values, the most appropriate combination ratio between the neat BER, and HSP‐NaOH was determined as 50:50. [ABSTRACT FROM AUTHOR]

This research is conducted with the objective of developing a multi‐functional finishing on cotton fabric for improving different properties such as self‐cleaning, antibacterial, ultraviolet blocking, mechanical, and electrical conductivity. To this end, zinc stannate nanophotocatalyst and reduced graphene oxide (RGO) are successfully synthesized and used for multifunctional treatment of cotton fabrics. Self‐cleaning properties under sunlight irradiation and antibacterial activities against two common pathogenic bacteria including Escherichia coli and Staphylococcus aureus are characterized on finished cotton samples. Electrical resistance and color of treated fabrics are also assessed. Electrical conductivity of the RGO‐coated fabrics is improved significantly due to presence of RGO on the surface of cotton fabrics. The treated cotton fabrics with zinc stannate nanocomposite show 61.7% photocatalytic self‐cleaning activity measured by degradation of methylene blue in aqueous solution under sunlight irradiation. Also, the zinc stannate nanocomposite‐coated cotton samples possess excellent antibacterial activity. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers (CNs) are isolated from cotton wool using subcritical water in a semiflow hydrothermal reactor to achieve green hydrolysis. The yield and crystallinity index (CI) of nanocellulose is optimized via varying temperatures and hydrolysis time while maintaining the pressure at 10 MPa. Under the subcritical condition, water dissociates into H3O+ and OH−, allowing protonation of the β‐glycosidic bond to hydrolyze cellulose strands into short chain fibers. Hydrolysis rates enhance with increasing temperatures, further disintegrating cellulose into smaller nanofibrils. At 180 °C, amorphous cellulose dissolution occurs, increasing the crystallinity without disintegrating the crystalline fibrous network. The concentration of H3O+ increases at 230 °C, further hydrolyzes cotton wool into uniform nanofibril cellulose with 14.3 ± 1.2 nm diameter. The tensile strength and elongation at break enhance using cellulose nanofibers obtained at 220 and 230 °C due to the small nanocellulose sizes that allow efficient dispersion in the poly(vinyl alcohol) (PVA) matrix. [ABSTRACT FROM AUTHOR]

Poly(amide‐imide) (PAI), serving as a synthetic polymer, has been widely used in industry for excellent mechanical properties, chemical resistance and high thermal stability. However, lack of suitable cell niche and biological activity limited the further application of PAI in biomedical engineering. Herein, silicon modified L‐phenylalanine derived poly(amide‐imide) (PAIS) was synthesized by introducing silica to L‐phenylalanine derived PAI to improve physicochemical and biological performances. The influence of silicon amount on physicochemical, immune, and angiogenic performances of PAIS were systemically studied. The results show that PAIS exerts excellent hydrophilic, mechanical, biological activity. PAIS shows no effects on the number of macrophages, but can regulate macrophage polarization and angiogenesis in a dose‐dependent manner. This study advanced our understanding of silicon modification in PAI can modulate cell responses via initiating silicon concentration regulation. The acquired knowledge will provide a new strategy to design and optimize biomedical PAI in the future. [ABSTRACT FROM AUTHOR]

Poly(3‐hydroxybutyrate‐co‐3‐hydroxyvalerate) (PHBV), member of the polyhydroxyalkanoate family, was generated from waste vegetable oil in a lab‐scale bioreactor and filled with pistachio shell (S) flour to produce fully agro‐industrial waste derived biodegradable low‐cost composites via melt mixing. To improve the interfacial interaction, maleic anhydride (MA) grafted PHBV (PHBV‐MA) was used as a compatibilizer and pretreatment of S (TS) was realized with silanization+alkalization process. The effects of filler percentage, compatibilizer, and S modification on the mechanical, thermal, morphological, water absorption, and biodegradability properties of the composite were studied. The crystallization percentage and temperature of PHBV were found to be higher in the composites, as compared with neat PHBV, due to nucleation effect of S/TS fillers. The increased tensile strength/modulus were achieved with composites including both PHBV‐MA compatibilizer and TS filler. The PHBV/PHBV‐MA/TS composite reinforced with 40% TS filler increased the tensile strength and modulus of the neat PHBV by 62.1% and 45.3%, respectively. Morphological analysis revealed that samples containing PHBV‐MA, or TS, have better surface wetting and interfacial adhesion than those without. The biodegradation of composites was studied over a 180 days of burial in soil. Biodegradation increased in tandem with the increase of the filler ratio in the PHBV composite from 20% to 40%. Biocomposites with 40% S/TS filler lost more than 90% of their weight, while the neat PHBV lost only 23.5%. Water absorption studies confirmed the biodegradability findings, with TS slightly reducing absorption capacity among the 40% filled samples due to the hydrophobicity effect of the silanization pretreatment. [ABSTRACT FROM AUTHOR]

In this study, we entirely replaced petroleum‐based bisphenol A (BPA) with unmodified kraft softwood lignin in epoxy resin formulation. Epoxidized lignin was prepared by reacting lignin with biobased epichlorohydrin (ECH) made from glycerol, and the formation of epoxide rings was confirmed by measuring the epoxy content of the epoxidized lignin using titration and Fourier‐transform infrared spectroscopy (FTIR). A fully biobased epoxy resin was then prepared by mixing the epoxidized lignin with a biobased curing agent derived from chew nutshell (from Cardolite Co.). Pre‐impregnated composite sheets were fabricated by impregnating unidirectional bamboo fibers with the developed water‐dispersion epoxy resin. The properties of the biobased composite samples were measured using a dynamic mechanical analyzer (DMA), scanning electron microscope (SEM), and a universal testing machine. The flexural strength of the lignin‐based epoxy composite was found to be 36% lower (14 MPa) compared to commercial epoxy (22 MPa). However, when bamboo fibers were added to the lignin‐based biocomposite (containing 25 wt.%), a higher flexural strength (116 MPa) was observed, representing an increase of 11% compared to the biocomposite made with EPON and bamboo fiber (104 MPa). Similarly, the addition of bamboo fibers to the lignin epoxy resulted in an increase in the flexural modulus by 1255% (from 0.42 to 5.69 GPa), while the flexural modulus of commercial epoxy was increased by only 736% (from 0.58 to 4.85 GPa). This was attributed to the higher compatibility of bamboo fiber with lignin, which is known to act as a natural glue in plants. [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]

This study aims to fabricate eco-friendly fiber metal laminates (FMLs) with acceptable flexural and impact properties. For this reason, the jute and basalt fibers are hybridized into the epoxy matrix and then sandwiched between 2024 aluminum layers. After that, various contents of montmorillonite nanoparticles are dispersed in these structures to enhance these mechanical properties. To characterize the effect of hybridizing fibers and incorporating nanoparticles, macrostructural and microstructural investigations are performed. In hybrid structures, the highest flexural and impact properties are achieved, when the basalt layers are placed as exterior layers of the composite core. However, in the FMLs containing nanoclay particles, the FMLs with the 1.5 or 3 wt% nanoclay have an acceptable improvement in the mechanical properties, which relates to the exfoliated or intercalated structure of nanoclay. Creating nanocomposite interlocks on the surface of aluminum layers, enhancing the adhesion bonding at the interface of metal/composite, and improving the adhesion between jute or basalt fibers with the epoxy matrix are the distinct improving mechanisms, which are characterized by macro- and microstructural methods. [ABSTRACT FROM AUTHOR]

The objective of this work was to develop new NR‐based biocomposite containing BioS and/or BL0 particles, which exhibit better tensile response, biocompatibility, and bioactivity for biomedical applications. Morphological, tensile, thermal, and biological tests were performed on the biocomposites to evaluate the influence of BioS and BL0 particles on the properties of the NR matrix. According to TG/DTG tests, the decomposition profiles of the NR/BioS and NR/BL0 biocomposites were similar to those of NR, whose main event could be seen in the 290–450°C temperature range, indicative of NR's structural degradation. Tensile analysis demonstrated that the addition of BioS or BL0 to the NR‐based biocomposite improved the elastic modulus and the tensile strength at break (σat break) in comparison to NR. The σat break value of the NR matrix increased from 0.99 ± 0.06 MPa to 1.84 ± 0.09 and 2.29 ± 0.04 MPa for the NR/BioS and NR/BL0 specimens with 30 wt%. Indirect cytotoxicity testing revealed that NR, NR/BL0, and NR/BioS biocomposite specimens promote the attachment of MSCs cell, that is, greater than 70% viability as defined in ISO 10993‐5:2009. The results indicate that BioS and BL0 particles have improved the tensile response and biological properties of the NR matrix, resulting in a range of potential biomedical applications. [ABSTRACT FROM AUTHOR]

An ever‐increasing rise in demand for sustainable materials has received significant attention in developing biocomposites for structural applications. In this regard, natural fibers replacing synthetic fibers as reinforcement in epoxy composite could be a significant gain toward sustainability, especially in automobile and structural applications. Herein, flax fiber/cellulose paper–reinforced epoxy biocomposite (FREC‐X) was fabricated via a vacuum infusion process. The influence of postcuring conditions (time and temperature) and cellulose paper density on the mechanical properties of FREC‐X was studied. The tensile strength and modulus of FREC‐X increased by 37% and 64%, respectively, upon the integration of paper. Postcuring FREC‐X further augmented the tensile and flexural properties of the composite, which could be attributed to the increase in cross‐linking of the epoxy and yields a strong polymer network. Fractography analysis confirmed that the composites integrated with paper showed fewer defects with improved interfacial adhesion. In addition, the water absorption and thickness swelling results revealed that the presence of cellulose paper marginally increased the water uptake and thickness swelling of FREC‐X. Furthermore, there was no significant change in the tensile and flexural properties of FREC‐X observed even after immersing in water for >200 h. Such properties of FREC‐X seen as a fascinating alternative to synthetic fibers and petroleum‐based epoxy and are promising material for sustainable development. [ABSTRACT FROM AUTHOR]

The present work highlights the preparation of the epoxidized natural rubber conjugated spent coffee biocomposites (ENR‐g‐SC) via one‐pot synthesis to control petroleum oil spills. The structural determination of the spent coffee grafted epoxidized natural rubber (ENR‐g‐SC) was confirmed through FTIR and 1H‐NMR spectroscopic analyses. The thermal performance, tensile tests, and morphological properties of the synthesized (ENR‐g‐SC) biocomposites were performed. The data revealed that ENR‐g‐SC biocomposite with 20 phr of spent coffee (SC) exhibited the highest tensile properties due to maximal chemical linkages of spent coffee and epoxide groups in ENR. The epoxidized natural rubber conjugated spent coffee copolymers were evaluated as oil sorbers for oil absorbency applications in chloroform, toluene, and 10% crude petroleum diluted with toluene. The data revealed that the oil absorbency increased slightly with chloroform or toluene instead of 10% crude oil diluted with toluene. Furthermore, swelling and network parameters including the maximum oil absorbency (Qmax), swelling rate constant (k), polymer‐solvent interaction (χ), effective crosslink density (ύe), equilibrium modulus of elasticity (GT), and average molecular weight between crosslinks (Mc) and theoretical crosslink density (ύt) were determined, and correlated to the efficiency of the synthesized epoxidized natural rubber conjugated spent coffee. [ABSTRACT FROM AUTHOR]

The impact of polymeric materials on the environment is a growing concern and an incentive for their commercial appeal. In composites, the trend is to replace matrices of synthetic polymers (SPs) with biopolymers (BPs) to develop bio‐based composites. The increasing demand for such materials has driven their research and application in many industrial sectors, often accompanied by increasingly restrictive fire safety regulations. With the aim of decreasing the flammability of composites, various approaches have been pursued, in particular the use of flame‐retardant (FR) additives. However, at high FR loads, the mechanical properties can be compromised. This article briefly overviews some aspects of the fire behavior and mechanical properties of BPs and bio‐based composites. Using a chart‐based framework and quadrant‐based quantitative analysis, the fire and mechanical properties of flame‐retarded composite formulations are evaluated simultaneously, aimed at comparing the effects of BPs and SPs in flame‐retarded polymeric composites in relation with other variables. [ABSTRACT FROM AUTHOR]

The present study details the composite fabrication, characterization, and full recyclability of the biobased polymer resins with flax fiber as the reinforcement. Two different biobased resins are selected by varying the resin hardener combination and curing parameters for the comparison. The optimum parameters for the composite preparation are finalized by evaluating the neat resin's mechanical and glass transition temperature (Tg) values. According to the results obtained, a biobased epoxy resin cured by a cleavable hardener displayed the highest Tg (i.e., 93.5°C) upon a two‐step cure cycle, guaranteeing full recyclability. Subsequently, eco‐composite flat panels are manufactured using the selected formulation reinforced with commercial flax‐based fabric. These panel's flexural strength, modulus, and interlaminar shear strength are measured after each curing step. The recyclability yield of the composite is tested, through a specific chemical process, demonstrating the possibility of separating and recovering both the constituent fibers and resin from the composite panels. [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]

Biocomposites have attracted researchers recently due to their biodegradability and environment‐friendly nature. The application of new fibers is increasing to reduce the fiber cost, and easy processing, and to meet the application‐specific properties in composite manufacturing. Banana is one of the most investigated plants for extracting fibers. Literature showed that the banana fibers were extracted from various parts of the plant. However, the potential of banana bracts is not discovered yet for composite manufacturing. In this work, the Robusta (AAA) variety banana bracts fibers (BBF) were prepared and used to make BBF reinforced polylactic acid (PLA) matrix biocomposites. Virgin PLA and BBF/PLA composites were prepared by two roll mills followed by compression molding. The characterization was carried out through X‐ray diffraction (XRD), Fourier transform infrared (FTIR), thermogravimetric analysis (TGA), and scanning electron microscopy (SEM), and the tensile, flexural, and impact properties were evaluated for Virgin PLA, BBF, and BBF/PLA composites. The FTIR results supported the incorporation of banana bracts in the composites by increasing the cellulosic and noncellulosic components. The SEM images supported the bonding of BBF in the PLA matrix. The BBF/PLA composite possessed the tensile strength of 40.15 ± 4.32 MPa, flexural strength (FS) of 87.13 ± 5.60 MPa, impact strength of 7.41 ± 0.56 kJ/m2, and a crystallinity index of 48.22%, which were significantly better than the virgin PLA. It was concluded that the BBF can be effectively used for making biocomposite with good mechanical strength. [ABSTRACT FROM AUTHOR]

The objective of the present study is to develop an environment friendly alternative material based on available and local bio‐source from the wastes of Algerian date palm trees, date palm twigs fiber (DPF) was selected as an effective reinforcing material for high density polyethylene (HDPE) biocomposite. Two types of treatments have been used including sodium hydroxide (NaOH) treatment to obtain DPF1 followed by potassium permanganate (KMnO4) treatment to obtain DPF2 for aim to improve fiber‐matrix compatibility, HDPE biocomposite reinforced with different ratios of DPF1 and DPF2 varying from 10 to 30 wt% were elaborated, characterized, and compared to select the preferred treatment and percent of DPF which can be used with high properties. The results obtained indicates that the incorporating of 30 wt% of DPF2 in HDPE biocomposite led to an improve in the mechanical and morphological properties. In fact, the improvement in interfacial properties improve ultimate biocomposite performance, and thus qualified its use in different industrial application. The maleic anhydride grafted high‐density polyethylene (HDPE‐g‐MA) was incorporated as a coupling agent to the reinforced biocomposite of 30 wt% DPF2/HDPE with two different loading (7 and 10 wt%), Also, the treatments were seen to enhance the tensile strength and elastic modulus. Additionally, the biocomposites observation by scanning electron microscopy (SEM) and atomic force microscopy (AFM) revealed more intimate contact between the fibers and HDEP matrix after surface modification. The results suggested that the successful sample with best characteristics which can be advised is 30 wt% DPF2/HDPE/10 wt% HDPE‐g‐MA, that offer their use in many applications particularly in the automotive industry. [ABSTRACT FROM AUTHOR]

In the present work, for the first time plasticized poly(vinyl alcohol) (PVA)/nanofibrillated cellulose (NFC) based biocomposite was crosslinked by citric acid (CA) using subcritical water/CO2 process. Presence of sufficient number of ‐OH groups in the backbone of plasticized PVA (p‐PVA) helps to form H bonding with SC‐NFC, which significantly improves the mechanical property of the biocomposite. Further, crosslinking of the same biocomposite helps to achieve hydrogel with superior modulus than that of PVA hydrogel alone. In subcritical medium, plasticized poly(vinyl alcohol)/nanofibrillated cellulose based biocomposite powder gets melted, fused and cross‐linked in a single step process to develop such hydrogel. Crosslinked plasticized poly(vinyl alcohol)/nanofibrillated cellulose based biocomposites were fully characterized in terms of gel content, thermal and chemical properties, morphology, swelling behavior and rheology. Excellent water swollen property, cellular structure and high storage modulus establish the potential of prepared biocomposite based hydrogels for several biomedical applications. [ABSTRACT FROM AUTHOR]

Temperature is a basic physical quantity that is essential to life and productivity. However, continuously and efficiently monitoring a full range of temperatures remains a serious challenge. Herein, a full‐range (−20 to 100 °C) flexible temperature sensor is designed using Ti3C2Tx MXene as an active conductive skeleton and sodium alginate hydrogel as a heat‐sensitive coating layer. The sensor exhibits accurate and stable temperature response across the entire range, with a sensitivity of up to 3244% °C−1. Moreover, it not only dynamically detects liquid nitrogen, but also effectively senses gradually approaching objects within a certain range. Lastly, a temperature monitoring system based on the sensor realizes the perfect monitoring of a cold‐storage model. This work will inject new vitality into the development of temperature sensors. [ABSTRACT FROM AUTHOR]

This work is aimed to develop, by means of conventional extrusion technologies for polymer processing, novel poly(lactide)/microcrystalline cellulose (PLA/MCC) filaments for 3D printing. The biocomposite filaments, produced at four different MCC loadings (6, 9, 12, and 18 wt%) by melt blending in extruder, are characterized in terms of rheological, thermal, and mechanical response. The analyses demonstrate that the MCC addition up to 12 wt% does not significantly modify the viscoelastic flow behavior of the matrix, and does not change its phase transition temperatures, but increases the storage modulus at 35°C by over 45%. [ABSTRACT FROM AUTHOR]

Summary: Ternary blend of gum acacia/pectin/pullulan (GPPL) polysaccharide composite film was prepared using solution casting technique with the addition of different ratios of glycerol and sorbitol to increase plasticiser—polysaccharide interactions. The results showed that the film thickness, water contact angle, moisture content, solubility, tensile strength, elongation and anti‐microbial properties were in good agreement with already reported films in the literature. Composite film solution was used as a coating solution to improve the shelf‐life of ivy gourd (Coccinia indica). Weight loss, titrable acidity (TA), total soluble solids (TSS), anti‐oxidant, total phenolic content (TPC) and storage time were measured to check the efficiency of the coating solution. The obtained data shows a 35% increase in the shelf‐life of the ivy gourd during the storage period of 23 days. The anti‐microbial test showed that the prepared film/coating is more resistant against Pseudomonas aeruginosa due to the presence of pullulan. Therefore, our coating shows a significant increase in shelf‐life of ivy gourd up to 23 days of storage time. Thus, the prepared polysaccharide composite films in this study may be suitable for food packaging applications whereas the composite film solution can be used to improve the shelf‐life of various food products in the food industry. [ABSTRACT FROM AUTHOR]

Ultra‐high molecular weight polyethylene (UHMWPE) is utilized in hip joints because of its high impact strength, outstanding fracture resistance, near‐zero moisture absorption, superior chemical inertness, and lower coefficient of friction than other polymers. However, because of the high melt viscosity of UHMWPE, the melt state approach gives unsatisfactory mechanical strength results. In this research, composite materials are fabricated by heat‐assisted compression molding having graphene nanoplatelets (GNPs) used as a filler material in a composition of (UHMWPE + 5 wt% hydroxyapatite nanoparticles) at three different wt% ages (i.e., 0, 1, 2, and 3 wt%). Here mechanical characteristics such as flexural, compression, and impact strength measurements according to ISO standards and SEM analysis are used to determine the aggregation of n‐HAp and GNP in UHMWPE. According to the authors' experimental results, biocomposite (with UHMWPE + 5 wt n‐HAp + 1 wt% GNP) has the lowest surface roughness value and excellent mechanical characterization compared to other compositions for hip joint. Flexural and compression strength improve by 25% and 40%, respectively, compared to pure UHMWPE. The multi‐objective optimization based on GRA‐AHP gives a better result at 5 wt% of hydroxyapatite nanoparticles and 1 wt% graphene nanoparticle reinforced in UHMWPE compared to other alternative materials. [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]

For climate and sustainability reasons, there is an interest and incentive to produce plastic and rubber products with increased content of a bio‐based component, preferably existing as an industrial by‐product, for example, wood powder/sawdust. There are many studies on the making of wood‐plastic composites, but hitherto very few consider vacuum forming as a processing technique, especially considering a biofiller. Here, the properties of a vacuum formed composite with thermally modified wood powder (with reduced water uptake) and a very ductile polyolefin, was reported. Surprisingly, even at a 15 wt% filler content, the composite remained ductile (extensibility of ca. 30%). The water uptake increased with increasing content of wood powder, but was never more than 5%. The water sorption kinetics indicated that the wood powder did not form a percolated continuous path through the material for easy access to the water, which led to a low water diffusivity (ca. 2 × 10−10 cm2 s−1). The calorimetric data showed that the biofiller, overall, did not affect the melting and crystallization behavior of the polymer matrix, nor the observed glass transition temperature. To conclude, vacuum forming was shown to be a viable technique for composites with a very ductile/elastic matrix and stiff fillers. [ABSTRACT FROM AUTHOR]

The objective of this study is to investigate the mechanical properties and visco‐elastic coefficients of the biocomposite material 15 mass% HA/PLA. The biocomposite material is manufactured using known technology: extrusion‐composition followed by injection molding. The general mechanical properties are evaluated experimentally using standard tensile and bending tests using five specimens made according to ASTM standards. The vasco‐elastic behavior is investigated using the DMA AR‐G2 Rheometer. The paper also investigates the microstructure of the mechanically stressed specimen breaking surface. Following the experimental research, a database is obtained in numerical form, diagrams, and fractographic images. The paper presents conclusions regarding the mechanical and dynamic behavior of the biocomposite material 15 mass% HA/PLA. The general results of the study provide practical guidance on the usefulness of biocomposite material 15 mass% HA/PLA for orthopedic biomedical applications. [ABSTRACT FROM AUTHOR]

Biocomposite materials are increasingly used in industrial transport structures (aerospace and automotive). They offer the ability to design complex parts, lightweight shapes that respond to high mechanical performance. Flax fibers are the most widely used because of their availability and mechanical properties, competitive to the properties of glass fibers. The detection of damage in these structures is essential to anticipate perilous consequences. Impacts induced damage is the most critical. The health control of a structure requires information about the severity and location of a damage through nondestructive methods. The aim of this study is to investigate vibratory behavior due to the impact on a biocomposite structure (flax/epoxy) to detect and evaluate the damage induced in noncontact method. [ABSTRACT FROM AUTHOR]

We report the production of pullulan (Pul)/chitosan (Chi)/graphene oxide (GO) composite films (CF‐Pul/Chi + GO). We observed that the addition of GO increases the film's roughness while keeping good GO dispersion. Both the strong interactions between Pul and Chi and the formation of hydrogen bonds between Chi and GO seem to be responsible for the formation of the composite film. The dielectric constant, Young's modulus and the tensile strength of the CF‐Pul/Chi + GO films exhibit maximum values at 1 μg mL−1 GO concentration. At GO concentrations higher than 1 μg mL−1, the interfacial layers between the polymer matrix and GO overlap, affecting the value of the dielectric constant and the mechanical properties of the films. Moreover, the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay carried out on LL47 fibroblast cells reveals that the CF‐Pul/Chi + 1 μg mL−1 GO films are not cytotoxic. In this regard, CF‐Pul/Chi 50/50 + 1 μg mL−1 GO has remarkable properties to be considered for a safe film with potential uses in the food, cosmetic and pharmaceutical industries. © 2022 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]

Bone is a hierarchical material that has inspired the design of biopolymer‐derived biocomposites for tissue engineering purposes. The present study sought to synthesize and perform the physicochemical characterization and biocompatibility of a collagen‐silica‐based biocomposite for potential application in bone tissue engineering. Ultrastructure, biodegradability, swelling behavior, and biocompatibility properties were analyzed to gain insight into the advantages and limitations to the use of this biomaterial as a bone substitute. Scanning electron microscopy analysis showed a packed‐collagen fibril matrix and silica particles in the biocomposite three‐dimensional structure. As shown by analysis of in vitro swelling behavior and biodegradability, it would seem that the material swelled soon after implantation and then suffered degradation. Biocompatibility properties were analyzed in vivo 14‐days postimplantation using an experimental model in Wistar rats. The biocomposite was placed inside the hematopoietic bone marrow compartment of both tibiae (n = 16). Newly formed woven bone was observed in response to both materials. Unlike the pure‐collagen‐tissue interface, extensive areas of osseointegration were observed at the biocomposite‐tissue interface, which would indicate that silica particles stimulated new bone formation. Agglomerates of finely particulate material with no inflammatory infiltrate or multinucleated giant cells were observed in the bone marrow implanted with the biocomposite. The biocomposite showed good biocompatibility properties. Further studies are necessary to evaluate their biological behavior over time. [ABSTRACT FROM AUTHOR]

Thermoplastic starch (TPS)/soy pulp (soy waste) composites (TSS) with varying compositions are successfully prepared in an internal mixer followed by compression molding. The mechanical, water absorption, and biodegradable properties of the developed composites are studied and compared with virgin TPS and cellulose reinforced TPS composites (TSC). Optimum tensile and flexural strength is observed for TSS and TSC composites with 10 wt.% soy waste and cellulose. Fourier Transform Infrared Spectroscopy (FT‐IR) and Scanning Electron Microscope (SEM) analyses indicated the interaction occurred between soy pulp/cellulose and TPS. Water absorptivity is found to increase from 6.2% to as high as 42.3% with the addition of 0 to 25 wt.% cellulose filler to the TPS matrix. Moreover, the soil burial degradation study shows higher degradability of the composites with a higher amount of soy pulp/cellulose. The developed composites show moderate mechanical properties with a hydrophobic and biodegradable nature. Therefore, there is a great possibility for these biocomposites to be utilized in applications such as disposable items, packaging materials, office cuboids, and transport sectors. [ABSTRACT FROM AUTHOR]

Every year, agrifood activities generate a large amount of plant byproducts, which have a low economical value. However, the valorization of these byproducts can contribute to increasing the intake of dietary fibers and reducing the environmental pollution. This review presents an overview of a wide variety of agricultural wastes applied in the formulation of different food products and sustainable packaging. In general, the incorporation of fibers into bakery, meat, and dairy products was successful, especially at a level of 10% or less. Fibers from a variety of crops improved the consistency, texture, and stability of sauce formulations without affecting sensory quality. In addition, fiber fortification (0.01–6.4%) presented considerable advantages in terms of rheology, texture, melting behavior, and fat replacement of ice cream, but in some cases had a negative impact on color and mouthfeel. In the case of beverages, promising effects on texture, viscosity, stability, and appetite control were obtained by the addition of soluble dietary fibers from grains and fruits with small particle size. Biocomposites used in packaging benefited from reinforcing effects of various plant fiber sources, but the extent of modification depended on the matrix type, fiber pretreatment, and concentration. The information synthesized in this contribution can be used as a tool to screen and select the most promising fiber source, fiber concentration, and pretreatment for specific food applications and sustainable packaging. [ABSTRACT FROM AUTHOR]