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In recent scenario, biocomposites are considered counterpart to synthetic fiber reinforced polymer composites due to their comparable specific mechanical characteristics, sustainability, low energy consumption during manufacturing, low cost and biodegradable nature. In this investigation, the influence of fiber loading and sodium hydroxide (NaOH) treatment on thermo-mechanical, morphological and water absorption properties of Areca Catechu tree peduncle fibers (ACTPFs) reinforced in Unsaturated Polyester Resin (UPR) matrix biocomposite has been explored. The biocomposites with 40 wt.% of ACTPF exhibited maximum mechanical characteristics with tensile, flexural, hardness and impact properties of 63 MPa, 56 MPa, 68 HRRW and 5.33 J/cm2 respectively. Also, the NaOH treatment of ACTPF reinforcement improved the tensile, flexural, hardness and impact properties of biocomposite specimens by 3.9%, 4%, 4.12% and 4.4% respectively. The scanning electron microscopic (SEM) images, X-ray diffraction (XRD) spectrum and Fourier Transform Infrared (FTIR) spectrum of the biocomposites were witnessed to ensure its suitability in industrial applications. The acceptable hydrophilic nature, less density and thermal stability up to 237 °C of biocomposite specimens achieved through NaOH-treated ACTPF reinforcements suit well for interiors of automobile and aerospace sectors. [ABSTRACT FROM AUTHOR]

Bone cement based on magnesium phosphate has extremely favorable properties for its application as a bioactive bone substitute. However, further improvement is still expected due to difficult injectability and high brittleness. This paper reported the preparation of novel biocomposite cement, classified as dual-setting, obtained through ceramic hydration reaction and polymer cross-linking. Cement was composed of magnesium potassium phosphate and sodium alginate cross-linked with calcium carbonate and gluconolactone. The properties of the obtained composite material and the influence of sodium alginate modification on cement reaction were investigated. Our results indicated that proposed cements have several advantages compared to ceramic cement, like shortened curing time, diverse microstructure, increased wettability and biodegradability and improved paste cohesion and injectability. The magnesium phosphate cement with 1.50% sodium alginate obtained using a powder-to-liquid ratio of 2.5 g/mL and cross-linking ratio 90/120 of GDL/CC showed the most favorable properties, with no adverse effect on mechanical strength and osteoblasts cytocompatibility. Overall, our research suggested that this novel cement might have promising medical application prospects, especially in minimally invasive procedures. [ABSTRACT FROM AUTHOR]

Efforts are ongoing to utilise agricultural waste to achieve a full resource use approach. Bambara groundnut is an important crop widely grown in the sub-Saharan Africa with potential future importance because of its resilience to thrive under heightened weather uncertainty and widespread droughts that have challenged food security. After harvesting, the edible nuts are separated from the shells which are discarded as waste. Therefore, this research is aimed at characterising the chemical composition and the structural properties of Bambara groundnut shells (BGS) in view of their potential application as a biomass for different bio-products. The chemical composition of BGS was found to be 42.4% cellulose, 27.8% hemicellulose, 13% lignin and 16.8% extractives. Proximate analysis showed a high amount of volatile matter (69.1%) and low moisture (4.4%). XRD analysis confirmed crystallinity of cellulose I polymer and FTIR analysis observed functional groups of lignocellulosic compounds. Thermal stability, maximum degradation temperature and activation energy were found to be 178.5 °C, 305.7 °C and 49.4 kJ/mol, respectively. Compared to other nutshells, BGS were found to have a relatively high amount of cellulose and crystallinity that may result in biocomposites with improved mechanical properties. [ABSTRACT FROM AUTHOR]

Our study presents an innovative material for application in the construction of biocomposites produced from agro-industrial by-products, constituted by the matrix of 70% raw rice bran, reinforced with 15% of rice husk fibers of different particle sizes (> 1 mm, > 500 µm, > 250 µm and < 250 µm) and 15% glycerol as a plasticizer. The materials were manually mixed and then molded by thermal compression in a hydraulic press with heating using a tray format. The molded parts were submitted to tests of biodegradability, contact angle, water absorption and impact resistance. The obtained results showed the influence of the incorporation of the rice husk fibers in the improvement of the evaluated properties when compared to the biocomposite produced only with rice bran. The different particle sizes of the rice husk fibers used in this study presented minor influence on the evaluated properties. Nevertheless, it should be noted that biocomposites with grain sizes > 250 µm and < 500 µm showed significant improvements, such as greater impact performance, higher initial contact angle and minor mass losses in composting experiments. [ABSTRACT FROM AUTHOR]

Various treatments, such as alkaline and silane treatments, are commonly applied to natural fillers before production to enhance their quality, thermal stability, and water absorption capacity and improve the fiber–matrix interface properties. However, these processes are not environmentally friendly and may escalate the production cost of composites due to the need for additional processing steps in mass production. This study delves into the impact of untreated walnut shell (WS) filler material, employed in varying ratios (ranging from 10 to 40%) as a filler, on the mechanical, thermal, morphological, and physical properties of environmentally friendly polylactic acid (PLA) matrix composites. The experimental results highlight a significant decrease in tensile modulus by 28%, tensile strength ranging from 32 to 65%, a decrease in flexural modulus by 22%, and flexural strength ranging from 24 to 58% with varying WS filler ratios. Time-dependent water absorption and increased density were observed. FT-IR analysis indicates structural similarities, while DSC results show minimal effects on glass transition temperature and crystallinity. TGA results reveal reduced thermal stability with increasing WS content. SEM microstructure imaging demonstrates homogeneous WS particle distribution, but higher WS content leads to increased brittleness and diminished resistance properties. In conclusion, this study underscores the importance of balancing sustainability through WS filler ratios while preserving mechanical performance. [ABSTRACT FROM AUTHOR]

Agricultural activities contribute to numerous waste problems and have emerged as a significant environmental concern. Nondegradable plastic residues decompose, releasing microplastics and affecting ecosystems and the environment. Consequently, biodegradable bio-composite films consisting of polylactic acid (PLA), natural rubber (NR), and rice straw (RS) have been developed with the aim of using them in agricultural applications. In this study, the PLA/NR blend, at a fixed ratio of 60/40 wt%, was filled with 3 and 5 wt% RS powder and extruded through a slit die into films. The biodegradability of all films was examined after being buried for 90 days in soil with a moisture content of 30% by weight. The neat PLA film showed the lowest weight loss percentage, 3.33%, suggesting a comparatively slower degradation rate in comparison to the PLA/NR(60:40) blend and all bio-composite films. The presence of 40 wt% NR in the film helped accelerate the biodegradation process during soil burial. The film produced from PLA/NR 60:40 wt% matrix filled with RS at 5 wt% led to rapid degradation, leading to a weight loss of 8.30%. From SEM micrographs, the morphology of all polymers after burial in soil showed fractures, the formation of pores, and obvious surface indications of fungi growing. The content of carbon decreased after soil burial, while oxygen content increased, and nitrogen was detected. The XRD analysis revealed low crystallinity in the neat PLA, consistent with the DSC analysis. The addition of NR and RS to the composites led to an increase in the crystallinity of PLA phase. All investigated materials exhibited an increase in crystallinity after being buried in soil. This research demonstrates that bio-composite films manufactured from the PLA/NR(60:40) blend filled with RS degrade more easily than unmodified PLA film. [ABSTRACT FROM AUTHOR]

Cellulose nanofiber–blended polylactic acid composites were prepared to enhance biodegradable polymers, which are expected to be a viable solution to the recent plastic waste crisis. The cellulose nanofibers were prepared by extracting cellulose fibers from bamboo using high-temperature and high-pressure steam and then disintegrating the fibers to the nanoscale. The optimum conditions for the processing pressure of the high-temperature and high-pressure steam treatments and the extraction process grinding time were investigated. Furthermore, the mixing ratio of cellulose nanofibers and polylactic acid for the fabrication of the composites was examined. The results show that the best condition was a 1:1 (50 wt% CNF) blend of cellulose nanofibers made with 15 atm of steam pressure for 5 min of steaming time followed by 10 s of milling time to make composites with polylactic acid that had 2.35 times the strength (77.5 MPa/g/cm3) of polylactic acid alone (33.3 MPa/g/cm3). This indicates that cellulose nanofibers produced from bamboo using high-temperature and high-pressure steam treatments can be used as reinforcing materials for low-strength biodegradable polymers. [ABSTRACT FROM AUTHOR]

The purpose of this study is to extract cellulose from corn silk (CS) fiber and use it as a reinforcing filler in unsaturated polyester resin (UPR) matrix. In this study, the cellulose is characterized using a Fourier Transform Infrared Spectrometer (FTIR), and the resulting UPR/cellulose biocomposite's mechanical properties (such as flexural and impact testing) are assessed. Scanning electron microscopy (SEM) provided strong support for mechanical rather than a chemical bond between fiber and UPR. Additionally, the sodium hydroxide treated CS in UPR biocomposite and comparing it with neat UPR. The agricultural byproduct rich in cellulose corn silk is a natural polymer known for its structural strength and UPR has garnered attention as a biopolymer with notable flexibility, making it an appealing choice for plastic product manufacturing. However, the drawback of UPR lies in its inherent deficiency in both stiffness and strength. According to the FTIR data, extracted cellulose (CS) had fewer ketone (C = O) and hydroxyl (-OH) groups than virgin cellulose. It was shown that throughout the extraction process, hemicellulose and lignin were more eliminated, producing a more pure form of cellulose. When filled in UPR, cellulose and treated CS both caused the impact strength of UPR biocomposites to drop. For both treated CS and cellulose, it was shown that the flexural modulus and flexural strength increased as the filler amount increased to a definite percentage (12%) after which it decreased. The result revealed the tensile strength and tensile modulus achieved by 0% of fiber with 48 N/mm2 and 51 N/mm2 and highest at 12% of fiber with 54.3 N/mm2 and 68.8 N/mm2 for CS + UPR. And 53.4 N/mm2 and 69.6 N/mm2 for cellulose + UPR composite,, respectively. In comparison, the flexural characteristics of UPR/cellulose were marginally inferior to those of UPR/treated CS. However, the impact resistance showed a significant improvement, particularly with a cellulose loading of 12%. Hence, cellulose presents a greater potential for composite manufacturing due to its ability to maintain the ductile properties of UPR compared to treated CS. Moreover, processed CS and cellulose both can be used as reinforcing agents in polymers to increase their strength and stiffness. [ABSTRACT FROM AUTHOR]

Bio-based composites with passive control layers were investigated by means of a comprehensive set of experiments. The structure, composed of an exterior layer of PLA/Flax and an inserted rubber layer, were manufactured using 3D printing technology. Tensile tests on PLA/Flax and rubber specimens revealed that it exhibited higher stiffness, whereas rubber demonstrated superior elongation. Additionally, three-point bending tests were conducted on 3D-printed composites with varying viscoelastic layer thicknesses (VL) to assess their bending performance. However, the composite with a single 1-mm thick viscoelastic layer (V1t1) showed optimal deflection and stiffness compared to counterparts with different viscoelastic layers. Furthermore, resonance vibration experiments were performed to investigate dynamic parameters such as frequencies and modal loss factors. Based on the experiments, it was determined that V1t1 was the composite that offered the optimal compromise between mechanical and vibration behavior due to its excellent damping characteristics. [ABSTRACT FROM AUTHOR]

The aim of the present study is to use beech wood flour (WF) and expanded ethylene vinyl acetate (EVA) copolymer industrial waste to develop a sustainable composite and its production method for further engineering use. Polyamide (PA) powder waste obtained after multiple selective laser sintering (SLS) thermal cycles was used to increase the strength and adhesion between the waste composite components. The morphological, mechanical, and thermal properties of the EVA/WF composites were characterised along with their interfacial wetting and water absorption properties. Optical and electron microscopy investigations revealed that the composites prepared have homogeneous dispersion and good interfacial adhesion between EVA and wood. The addition of SLS waste PA powder increases the strength and stiffness of the composite developed. The composite with 40 wt% WF exhibited the best water absorption, mechanical properties, and processability among the various compositions. The sustainable composite proposed can replace commercially available materials, which helps to save resources and reduce waste. [ABSTRACT FROM AUTHOR]

Releasing of large volumes of leather scraps wastes from different leather, footwear, and leather goods industries has become a major environmental pollution concern now a days in developing countries. Natural nanofibers are widely used as prospective reinforcement materials in formulation of different biocomposites materials. Herein, a new nanocomposite material has been synthesized and characterized using leather scraps wastes and Slender amaranth based nano-cellulose with latex in a clean environment perspective. Nano-cellulose was extracted from Slender amaranth vegetable wastes as natural fiber for green composites preparation. The extracted nanofibers, leather waste composite, and the resulting nanocomposite material have been characterized using X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and Field emission scanning electron microscopy (FESEM). Different physio-mechanical characteristics of nanocomposite were evaluated which showed its potential applications as shoe upper components. The results revealed that addition of nano-cellulose significantly improved the physical properties of new composite sheet. SEM images revealed the surface morphology of nanocomposite which was observed to be predominantly homogenous with uniform distribution of particles. This novel nanocomposite exhibits different potential properties and TGA data showed higher thermal stability of this material in comparison to those obtained with control method. It can find application as a green reinforcement material in the preparation of different leather goods with improved mechanical properties and thermal stability. These significant findings highlight the preparation of a valuable biocomposite material from leather solid wastes which is cost effective and sustainable for leather industries as well as it emphasizes an effective approach to reduce environmental pollution. [ABSTRACT FROM AUTHOR]

Natural chitin/CaCO3 (ChCC) complex derived from crab shell was modified and used to fabricate an organic/inorganic complex filler to enhance the optical and mechanical properties of polylactic acid (PLA) biocomposite. Crab shell was treated with NaOH to remove proteins and pulverized to produce ChCC microparticles having flake-like shape. The presence of CaCO3 in ChCC enhanced the hydrophobicity of the microparticles after treatment with fatty acids. The ChCC-filled PLA composite films prepared via melt extrusion displayed good optical properties without harsh discoloration (ΔE of 0.9%). In contrast, the film filled only with chitin showed high ΔE of 15% at same filler content, which is not commonly observed in biopolymer-filled biocomposites. Also, the ChCC-filled film exhibited higher mechanical properties, with an 8% increase in tensile strength compared to PLA, while the chitin-filled film showed a decreased tensile strength of 6% than PLA, which was attributed to the improved compatibility between the hydrophobic ChCC and the PLA matrix. The inexpensive preparation of ChCC and its application as a biocomposite filler is an attractive use of crab shell waste. [ABSTRACT FROM AUTHOR]

Sustainable poly(lactic acid) (PLA)/propylparaben (PPB) composite based films were fabricated via solution casting approach. The assessment of PLA/PPB composite films in terms of active food packaging characteristics like thermal, mechanical, UV–Vis, oxygen barrier, anti-bacterial as well as anti-oxidant effect is carried out. The PLA/PPB-5 composite film resulted in three-fold (23%) increase of elongation-at-break while maintaining a tensile strength (42 MPa) in comparison with PLA film. Consequently, the PLA/PPB-5 composite film displayed a 70% UV–B blockage and reduced the oxygen transmission rate by 52% as compared to PLA film. Further, the PLA/PPB-5 composite film exhibited significant improvement (52%) in the radical scavenging activity which can be really helpful to keep the food products fresh for longer periods. The PLA/PPB filler showed good antibacterial activity against food-borne bacteria [Staphylococcus aureus and Escherichia coli]. The fabricated PLA/PPB composite films have shown desirable active food packaging characteristics and therefore may be suitable for food packaging applications. [ABSTRACT FROM AUTHOR]

The canola oil industry generates significant waste as canola meal (CM) which has limited scope and applications. This study demonstrates the possibility of valorization of CM as a sustainable natural filler in a biodegradable polymer composite of Poly(lactic acid) (PLA). Generally, interfacial bonding between natural fibers and the polymer matrix in the composite is weak and non-uniform. One possible solution is to derivatize natural fibre to introduce interfacial bond strength and compatibility with the PLA polymer matrix. Here, CM was succinylated in a reactive extrusion process using succinic anhydride at 30 wt% to get 14% derivatization with 0.02 g of -COOH density per g of CM. The CM or succinylated CM at 5 and 15 wt% was co-extruded with amorphous PLA to get composite fibers. CM-PLA and succinylated CM-PLA biocomposites were foamed using a mild and green microcellular foaming process, with CO2 as an impregnating agent without any addition of organic solvents. The properties of the foams were analyzed using differential scanning calorimetry (DSC), Dynamic mechanical thermal analysis (DMTA), shrinkage, and imaging. The addition of CM or succinylated CM as a natural filler did not significantly change the glass transition temperature, melting point, percent crystallization, stiffness, and thermal stability of PLA foams. This suggests succinylation (modification) of CM is not a mandatory step for improving interphase compatibility with the amorphous PLA. The new PLA-CM foams can be a good alternative in the packaging industry replacing the existing petroleum-based polymer foams. Highlights: Valorization of CM as a sustainable natural filler in PLA biocomposite foams Modification of CM is not mandatory for interphase compatibility with the PLA PLA-CM foams have similar appearance and properties to control PLA foams New PLA-CM foams can be a good alternative in the packaging industry [ABSTRACT FROM AUTHOR]

In this study, a biogenic magnetic nanocomposite, HAP@DEX@MNP, using hydroxyapatite from eggshell waste and dextran was developed to efficiently remove 2,4-D from aqueous solutions. The magnetic nano biocomposite underwent rigorous characterization using a comprehensive suite of analytical techniques, including FTIR, XRD, FESEM, EDX, TEM, and VSM. FTIR analysis was used to validate the existence of pivotal functional groups, such as phosphate, carbonyl, hydroxyl, and iron oxide. XRD analysis verified both the crystalline nature of hydroxyapatite and the successful integration of dextran and hematite within the composite structure. FESEM and EDX examinations provided valuable insights into the surface morphology and elemental composition. TEM observations elucidated the existence of nano-sized particles underscoring the unique structural characteristics of the nanocomposite. Batch adsorption experiments were conducted under optimized conditions, highlighting the critical role of pH 2 for efficient 2,4-D removal. The mechanisms driving the binding of 2,4-D to HAP@DEX@MNP were found to encompass diverse interactions, encompassing electrostatic forces, hydrogen bonding, π-π interactions, and van der Waals forces. Adsorption isotherm studies revealed both monolayer and multilayer adsorption, with the Langmuir and Freundlich models fitting well, indicating a maximal adsorption capacity of 217.39 µg/g at 25 °C. Kinetic investigations supported the pseudo-second-order model for efficient adsorption dynamics, and thermodynamic analysis emphasized the versatility of HAP@DEX@MNP across different temperatures. Importantly, the study highlighted the remarkable regenerative capacity of the nanocomposite using a 0.1 M NaOH solution, positioning it as an environmentally friendly option for water treatment. In conclusion, HAP@DEX@MNP holds significant potential for diverse applications in addressing global water treatment and environmental challenges. [ABSTRACT FROM AUTHOR]

This study describes a novel spray-on mulch material as an alternative to currently used weed control methods. The mulch material is based on renewable raw materials, mainly rapeseed oil, starch and sodium alginate. Laboratory tests were conducted to obtain a mulch material with the best possible properties. Formulations with different ingredients were prepared and tested for their material properties. The formulations were investigated for potential shrinkage tendency and heat resistance as well as water resistance. Further tests such as resistance to mould infestation and aerobic degradability according to DIN EN ISO 17556 were carried out with the formulation that performed best in the previous tests. Mould resistance was enhanced by adding sodium benzoate. In the laboratory experiment, the CO2 decomposition rate was about 30% after seven weeks. With the favouritised variant, which was found step by step through the experiments, an outdoor field test was carried out to investigate the durability under natural conditions over the vegetation period. In the field, the mulch material maintained its function for six months. In the greenhouse, the effect of the mulch material on weeds was studied. It was found that the mulch material showed a high efficiency in controlling above-ground biomass of Elymus repens, Amaranthus retroflexus, and Setaria viridis. In addition, the biomass of the roots of Amaranthus retroflexus and Elymus repens was reduced. Further studies are on the way to elucidate field suitability and the weed suppressive effect under different environmental conditions. [ABSTRACT FROM AUTHOR]

Bio-based materials are becoming increasingly important as demand for conventional wood-based products raises environmental issues, potentially leading to deforestation. As a result, environmentally acceptable, cost-effective, and easily available alternative natural biomass materials for these intended utilizes are highly required. In this work, a waste wheat straw cellulose polymer matrix composite reinforced with sisal fiber through physical and chemical treatment methods for fiberboard application was synthesized and characterized. The composite materials were developed using the polymer solution casting method. Waste wheat straw composites with 0, 5, 10, 15, 20, 25, and 30 wt% of sisal fiber with respect to the matrix were prepared. Qualitative and quantitative approaches, as well as exploratory and experimental research methods, were employed. Fourier transform infrared (FTIR) spectroscopy was used to investigate the functional group of wheat straw cellulose, while scanning electron microscopy (SEM) was used to examine the sisal fiber morphology. Flexural strength was tested by using a universal testing machine, and impact strengths were measured by a V-notch Charpy tester based on medium-density fiberboard (MDF) and low-density fiberboard (LDF) as control samples. The water absorption of the samples was also studied. The work complied with ANSI A208.2–2002's general test standards for general usage. The results showed that the maximum flexural strength attained at 20 wt% of reinforcement was (56.83 MPa) and the impact strength at 20 wt% sisal fiber was (30.33 J), while the MDF and LDF control samples' flexural strengths were 35.5 MPa and 41.5 MPa, respectively, and the impact strengths were (20.16 J and 25 J), respectively. The lowest water absorption value was achieved at 5 wt% of sisal fiber, and the value was (2.09%). However, water absorption of (74.04%) for MDF and (106.98%) for LDF was measured. Thus, it was discovered that using waste biomass such as wheat straw instead of raw wood may provide a composite material with superior flexural strength, impact strength, and reduced water absorption for fiberboard applications. [ABSTRACT FROM AUTHOR]

The escalating significance of 3D printing in various industries is underscored by its ability to rapidly and cost-effectively produce distinctive parts. Among the 3D printing methods, fused filament fabrication (FFF) has emerged as a highly productive and cost-effective approach. While extensive efforts have been made to enhance the qualities of FFF products, challenges persist in material availability and quality compared to traditional methods. This study provides a meticulous overview of the FFF process, delving into various 3D printing processes, polymers, and polymer composites. Despite documented efforts to augment mechanical, thermal, and electrical properties, material constraints remain a focal point. Our analysis extends to various PLA/biocomposites, shedding light on achieved improvements and potential applications. Looking forward, the future trend in FFF technology suggests a paradigm shift towards enhanced material diversity and performance. Anticipated applications span beyond traditional use cases, encompassing sustainable manufacturing, medical devices, and eco-friendly construction materials. This comprehensive review not only consolidates the current state of FFF and PLA-biocomposites but also anticipates future trends and potential applications. This research enhances the current knowledge of additive manufacturing and sets a standard for assessing developments in FFF technology by comparing them to previous works. [ABSTRACT FROM AUTHOR]

The solid waste generated by the disposal of plastic materials has become one of society's major problems in recent years. In this sense, several researchers have sought alternatives to minimize environmental pollution. A promising option would be using natural materials, biopolymers, or a mixture of these, also known as composites. In this study, composite films were prepared based on babassu mesocarp (BM) and palygorskite clay mineral (Pal), using the casting technique, as well as the plasticizers sodium alginate (SA) and glycerol (Gl). The films obtained were called BM/SA/Gl/Pal, and for comparison were, prepared films containing BM and BM/SA/Gl. The films presented uniform color, smooth and shiny surfaces, and no fissures. FTIR analysis indicated possible interactions between clay and matrix. The SEM analysis showed that the BM film presented more significant surface irregularity. In contrast, the BM/SA/Gl/Pal film gave a more regular topography and excellent thermal stability. Finally, the BM/SA/Gl/Pal film showed more promising results when compared to the others and is considered an attractive material for use in biodegradable packaging. [ABSTRACT FROM AUTHOR]

Pandanus amaryllifolius fibre (PAF) is an agricultural waste plant derived from the natural cellulosic source of fibre that can be used in various bio-material applications. In the present study, a novel biodegradable thermoplastic cassava starch/beeswax blends reinforced with Pandanus amaryllifolius fibre (TCPS/BW/PAF) bio-composites were successfully developed at varied Pandanus amaryllifolius fibre concentrations of 0, 10, 20, 30, 40, 50 and 60 wt% while beeswax loading was remained constant at 2.5 wt% concentration using hot moulding compression method. A comprehensive characterisation of TCPS/BW/PAF bio-composites was examined in terms of their physical, mechanical, thermal and biodegradation properties. The addition of Pandanus amaryllifolius fibre has significantly improved tensile strength and tensile modulus at maximum value obtained 10.9 and 606.5 MPa, respectively as well as flexural strength and flexural modulus of bio-composite at maximum value obtained 21.37 and 523.76 MPa, respectively until 50 wt% Pandanus amaryllifolius fibre loading. Surface morphology of the fractured tensile samples PAF10 to PAF50 shows compacted structure and fibre breakage, indicating effective stress transfer from starch matrix to PAF during tensile force application. Furthermore, the addition of Pandanus amaryllifolius fibre improved thermal stability from TG, DTG and DSC results; improved crystallinity from XRD analysis; reduced water and moisture affinity from physical properties testing, and lowered the biodegradation rate. Overall, this study shows the potential of TCPS/BW/PAF bio-composites in biopolymer application and bio-packaging industries. [ABSTRACT FROM AUTHOR]

To incorporate sustainability in polymer composites, industries prefer natural fibers as reinforcement material owing to its specific mechanical properties. This study investigates the characterization of sodium hydroxide–treated Agave Tequilana Fibers (ATFs) reinforced in unsaturated polyester resin (UPR) matrix composite with nanosized Silicon Carbide (SiC) particles as filler material. The composite specimens were manufactured by compression moulding technique. The alkali-treated ATF (AATF) reinforced composite (AATFC) specimens with 40 wt.% of AATF were impregnated with different wt.% SiC nanoparticles as 1 wt.%, 2 wt.% and 3 wt.%. The effect of wt.% of SiC nanoparticles on mechanical, wear and moisture absorption characteristics of AATFC specimens were described. It was found that AATFC specimens with 2 wt.% SiC nanoparticles exhibit maximum hardness value of 87 HRRW, tensile strength of 51.61 MPa, flexural strength of 61.73 MPa, and impact strength of 8.17 J/cm2. Similarly, the same composite specimen incurred a minimum wear weight loss of 0.013 g and moisture absorption characteristics with increase in weight of 0.016 g in normal water, 0.017 g in sea water, and 0.011 g in NaOH solution. On the other hand, agglomeration of SiC nanoparticles and its heterogeneous distribution in AATFC with 3 wt.% SiC nanoparticles resulted in declined properties. Also, the fractographic images of tensile failure cross-section of AATFC specimens help to estimate the interaction between UPR, AATF and SiC in the composites. The observed results favour the use of AATFC specimen in light weight structural applications. [ABSTRACT FROM AUTHOR]

Currently, there is a notable attraction within the industry towards biocomposites, driven by the increasing fascination with natural fiber-reinforced composites (NFRCs). These NFRCs offer remarkable benefits, including cost-effectiveness, biodegradability, eco-friendliness, and favorable mechanical properties. As a result, the manufacturing processes of natural fiber reinforced polymer (NFRP) composites have garnered attention from both industrial professionals and scientists. The emergence of these eco-friendly materials in the automotive and aerospace industries has sparked interest in understanding their production techniques. However, the machining processes of NFRP composites pose significant challenges due to the complex structure of natural fibers, necessitating thorough studies to address these issues effectively. This research paper presents a comprehensive investigation on surface roughness during the milling process of Alfa/epoxy biocomposites. A set of 100 experimental trials was conducted to test the surface roughness, and analysis of variance (ANOVA) was used to assess the impact of cutting parameters and chemical treatment on surface quality. To develop a predictive model for surface roughness, a hybrid approach called ANN-GA (artificial neural networks-genetic algorithms) is proposed in this research. This approach combines ANN and GA to determine an optimal neural network architecture. The performance of the ANN-GA model is compared to the Levenberg–Marquardt backpropagation (LM) algorithm. ANOVA results show that the feed per revolution have a significant influence on surface roughness, followed by the chemical treatment of fibers, while machining direction has a smaller effect. The ANN-GA model demonstrates good accuracy in surface roughness prediction compared to the LM algorithm. [ABSTRACT FROM AUTHOR]

Concerns about renewable energy and the environment are driving the development of high-performance manufactured products made from natural resources around the world. Natural fiber composites play an essential role in the advancement of high-performance engineering materials due to their ease of use, recyclability, and environmental friendliness. The noxious plant Lantana camara poses a serious threat to grazing cattle, biodiversity, land productivity, and, as a result, overall ecology. One of the potential strategies for limiting its invasion in agricultural and forest regions is by utilizing the L. camara stems as a source of lignocellulosic fiber in bio-composites. The main objective of this review article is to give a thorough overview of L. camara fibers and composites. Chemical modifications, manufacturing methods, the fabrication of the reinforced matrices, and also the mechanical, chemical, and morphological features of L. camara fiber-reinforced composites are reviewed comprehensively. Ultimately, this article identifies, examines, and fills gaps in past research and also offers useful information for future research in other streams that use L. camara fiber as reinforcement. [ABSTRACT FROM AUTHOR]

The study aimed to synthesis biocomposite material that was more bioactive and could be employed as a graft during bone formation. Cordierite was fabricated via sintering a mixture of 51.4% silicon oxide, 34.8% aluminum oxide, and 13.8% magnesium oxide at 1400 °C. The produced substance was identified using X-ray Diffraction (XRD), the patterns showed that just indialite was identified as a single phase. To formulate sample with supreme biological behavior, cordierite was added to hydroxyapatite in 30 wt% and then sintered at 1100 °C. Following, XRD reveals the emergence of the Mg-whitlockite phase. Scanning Electron Microscope (SEM) had been employed to investigate their morphology and the effect of treatment temperatures. Fourier-transform infrared spectroscopy (FTIR) employed to assess if there is chemical reaction between cordierite and hydroxyapatite was tack placed. Prepared ceramic powder used as reinforcing phase with 30, 40 and 50 wt% in PCL matrix to formulate biocomposite system. All samples were inspected via SEM to determine their microstructure. FTIR showed there is no chemical reaction occurred between PCL and ceramic powder and it was just a physical blending. Energy Dispersive X-ray (EDX) showed that Z40 exhibits the better composition, as compared with other samples, in terms of Ca/P ratio. Z40 hybrid composite promotes the better results in terms of microstructure and chemical composition. Also, employed better in vitro behavior represented by degradation rate that equal to 39.86%. The produced grafts shaped the maxillary sinus better, support displaced sinus mucosa, and fill the voids between the sinus floor bone wall. [ABSTRACT FROM AUTHOR]

Bio-based adsorbents for removing pollutants were prepared using composite sponges with porosities greater than 80%. Herein, we report for the first time the preparation of macroporous sponges via freeze-drying of a chitosan solution and water hyacinth fiber (WHF). Genipin, a chemical crosslinker, was utilized in the process. The results showed that genipin increased the resistance to compression of the sponges while also improving their water and thermal stability. The composite sponges effectively removed C.I. reactive orange 16 (RO16) from water, with adsorption capacities ranging from 37.86 to 95.77 mg/g at pH 7. After 24 h, nearly complete dye removal was achieved with an initial dye concentration of 20 mg/L and an adsorbent dose of 2.5 g/L. The adsorption isotherm followed the Freundlich model, and the adsorption kinetics followed the pseudo-second-order model. The WHF/chitosan sponge could be reused for up to four cycles. These findings demonstrate the potential of the prepared sponges as bio-based adsorbents for the treatment of dye-contaminated wastewater. [ABSTRACT FROM AUTHOR]

The application of continuous natural fibers as reinforcement in composite thin-walled structures offers a feasible approach to achieve light weight and high strength while remaining environmentally friendly. In addition, additive manufacturing technology provides a favorable process foundation for its realization. In this study, the printability and energy absorption properties of 3D printed continuous fiber reinforced thin-walled structures with different configurations were investigated. The results suggested that a low printing speed and a proper layer thickness would mitigate the printing defects within the structures. The printing geometry accuracy of the structures could be further improved by rounding the sharp corners with appropriate radii. This study successfully fabricated structures with various configurations characterized by high geometric accuracy through printing parameters optimization and path smoothing. Moreover, the compressive property and energy absorption characteristics of the structures under quasi-static axial compression were evaluated and compared. It was found that all studied thin-walled structures exhibited progressive folding deformation patterns during compression. In particular, energy absorption process was achieved through the combined damage modes of plastic deformation, fiber pullout and delamination. Furthermore, the comparison results showed that the hexagonal structure exhibited the best energy absorption performance. The study revealed the structure-mechanical property relationship of 3D printed continuous fiber reinforced composite thin-walled structures through the analysis of multiscale failure characteristics and load response, which is valuable for broadening their applications. [ABSTRACT FROM AUTHOR]

The coupling of silver (Ag) and iron oxide (Fe3O4) NPs and their interaction when incorporated in collagen (C)-based nanobiocomposite (NBC) have not been documented. The present investigation reports a simple and novel method for the development of magnetized antibacterial collagen-based NBC from biowaste that contains Ag–Fe3O4 NPs incorporated into the collagen matrix, which acts as reinforcement and also provides enhanced antibacterial effects for biomedical applications. Synthesized AgNPs were ascertained by UV–vis spectra. Characterization of Ag–Fe3O4 NPs was carried out using SEM, TEM, zeta potential, XRD, PSA, DSC, TGA, VSM and FTIR techniques. The particle size was found to be in the range 25–120 nm and the conjugated NPs showed less aggregation, as observed by SEM and TEM techniques. VSM results indicated the presence of magnetic property in Ag–Fe3O4 NPs, and thus, it can be isolated from medium and hence can be effectively used as a strategy for water purification. The results indicated enhanced antibacterial efficacy for C–Ag–Fe3O4 NBC where the Ag–Fe3O4 NPs inhibited the growth of E. coli (21.6 ± 1.3 mm) better than gram-positive species, S. aureus, which showed 18.7 ± 1.4 mm inhibition zone. Furthermore, C–Ag–Fe3O4 NBC showed enhanced thermal stability and tensile strength of 3.31 ± 0.43 MPa. The novelty of this study is that the fabricated magnetized antibacterial NBCs offer a quick, easy and clean way to recycle CCLW by producing eco-friendly materials. In addition, in vitro tests show that they are biocompatible and appropriate for tissue-engineered applications. The study demonstrates C–Ag–Fe3O4 NBC developed from biological waste with sustained efforts suitable for biological and biomedical applications. Fabrication of C-Ag-Fe3O4 NBC from biowaste for biomedical application [ABSTRACT FROM AUTHOR]

This study involved fabricating thermoplastic wheat starch–sugarcane bagasse biocomposites through melt mixing method. The effect of sugarcane bagasse concentration at 3 levels of 0 wt.%, 7.5 wt.% and 15 wt.% of wheat starch and sorbitol:glycerol weight ratio at 4 levels of 0:4, 1:4, 2:4 and 4:4 on their physicomechanical properties was evaluated. The results indicated that increasing both of the weight ratio of sorbitol to glycerol and the concentration of bagasse generally led to a significant increase in tensile strength and modulus, but a decrease in elongation at break and equilibrium moisture content. The biocomposite containing the weight ratio of sorbitol:glycerol of 0:4 and bagasse concentration of zero, had the lowest tensile strength (0.22 MPa) and tensile modulus (0.23 MPa), and the highest elongation at break (103.1%) and equilibrium moisture content (30.6%) and conversely The biocomposite containing the weight ratio of sorbitol:glycerol of 4:4 and bagasse concentration of 15, had the highest tensile strength (5.3 MPa) and tensile modulus (371.5 MPa), and the lowest elongation at break (1.5%) and equilibrium moisture content (20.6%). Moisture absorption was also studied using the Peleg model, which showed that samples with lower weight ratios of sorbitol to glycerol and lower bagasse concentrations had higher initial moisture absorption rates and greater moisture absorption capacity. The investigation of thermal behavior of the biocomposites by TGA analysis showed improved thermal stability of the biocomposites by increasing both of the sorbitol:glycerol weight ratio and the bagasse concentration. Finally, the FTIR spectrum revealed an increase in hydrogen and polar bonds in the biocomposites compared to pure starch. [ABSTRACT FROM AUTHOR]

Resistance of bacteria to antibiotics is a serious human concern since it affects medical treatments performance against bacterial infections. Within the scope of new robust antibiotics development, we propose a heterocyclic–clay composite material. It consists of the association of 5-(2 pyridyl)-1-3-4-oxadiazoles-2-thione with pre-treated montmorillonite (MMT). Different pre-treatments were considered including acidification (H+-MMT) and intercalation with polar polymers facilitating the antibacterial composite material synthesis. The different composite materials that vary in terms of oxadiazole concentration were characterized in terms of structure (molecular, crystalline) using FTIR and XRD, and antibacterial properties. The obtained results showed successful intercalation of polar polymeric materials within acidified montmorillonite clay. The final composite material showed very promising antibacterial properties with reference to two well established antibiotics i.e., Penicillin and Spiramycine. The highest performance was observed for the composite containing polyvinyl alcohol intercalating the acidified montmorillonite with 50 wt % of 1,3,4-oxadiazole compound. [ABSTRACT FROM AUTHOR]

This paper investigates the effects of adding montmorillonite and eggshell particles on the mechanical, morphological and water absorption properties of bamboo fiber reinforced composites for filler contents ranging from 1wt% to 3wt%. The results show an improvement in the water absorption, the thickness swelling and the mechanical properties of composites with a maximum filler content of 3wt%. Herein, the water absorption was reduced by 37.8 ± 0.29% and 25.7 ± 0.28% the montmorillonite and eggshell powder filled composites, respectively. The thickness swelling was similarly decreased by 36.9 ± 1.3% and 27.8 ± 0.23%, respectively. Under ambient relative humidity, the tensile and bending strengths and modulus of 3wt% montmorillonite and eggshell particle filled composites were found to drastically increase. However, they were slightly enhanced under wet conditions. The swelling, porosity as well as the dispersion quality of particles were analyzed and seemed to reduce the mechanical properties. [ABSTRACT FROM AUTHOR]

The purpose of the study is to synthesize a new biocomposite material by using the monomers acrylonitrile (AN) and acrylic acid (AA) with reinforcement of fish bone powder (FBP) and prediction of its mechanical properties by using an artificial neural network (ANN) model. The Fourier transform infrared (FTIR) analysis indicates the denaturation of collagen and the presence of amide I, II, carbonate, and phosphate groups. The variation of particle size and structure has been studied by scanning electron microscopy (SEM). The X-ray fluorescence (XRF) indicates the chemical composition of raw FBP and calcinated FBP. The thermo gravimetric analysis (TGA) shows the amount of weight loss of various samples at different temperatures. X-ray diffraction (XRD) indicates the homogeneous dispersion of FBP into the surface of the Poly (AN-co-AA) matrix and the crystallinity decreases due to the addition of FBP. The tensile strength of the biocomposite varies from 52 MPa to 66.5 MPa, impact strength varies from 3.4 J to 5.6 J, the flexural strength of the biocomposite varies from 44.1 MPa to 30.4 MPa, and hardness increases from 35 to 69 MPa. The synthesised biocomposite shows biodegradability and water absorption capability as compared to the copolymer matrix, which is due to the interaction of fish bone powder with the copolymer matrix. The mechanical properties were measured experimentally and predicted again by using the ANN model. The training and test datasets used in this analysis have a correlation factor of more than 0.9, indicating that the predicted result of mechanical properties is in good agreement with the experimental result. [ABSTRACT FROM AUTHOR]

The aim of this work was to enhance the performance of a wood pulp/polylactic acid (PLA) biocomposite using epoxidized natural rubber (ENR)–grafted-modified microfibrillated cellulose (MFC) as a novel compatibilizer. MFC was modified by two different methods of silanization:one with 3-(trimethoxysilyl) propyl methacrylate and the other with 3-aminopropyltriethoxyl silane. The two types of modified MFC were grafted onto ENR via a solution-casting method. Compared with the uncompatibilized biocomposite, the flexural strength and impact resistance of the biocomposite compatibilized with ENR-amino silanized MFC were increased by 168% and 261%, respectively. SEM images and DMTA analysis confirmed the compatibility among the three phases of pulp, PLA, and ENR. Meanwhile, the use of ENR-methacrylate silanized MFC as a compatibilizer in the biocomposite also demonstrated the improvement of compatibility compared with non-MFC and MFC systems. The durability of the biocomposites was assessed in an accelerated weathering test. The pulp/PLA/ENR-methacrylate silanized MFC showed the lowest degradation rate, due to the methacrylate group of silane acted as a chromophore to mitigate UV absorption. [ABSTRACT FROM AUTHOR]

Alginate–zinc oxide (Alg–ZnO) biocomposite was synthesized and tested as a chromium ions Cr(VI) adsorbent for environmental applications. Alg–ZnO biocomposite was prepared by the interaction between sodium alginate biopolymer and zinc oxide nanoparticles (ZnO–NPs), prepared by modified wet chemical method. The solid adsorption characteristics of the synthesized Alg–ZnO biocomposite were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV–Vis spectroscopy. Adsorption isotherms of chromium ions on the prepared Alg–ZnO biocomposite were investigated with varying the initial concentration of Cr(VI) under different application conditions such as pH, contact time, adsorbent dosage, and temperature. Adsorption of Cr(VI) was investigated by different isotherm models such as Langmuir, Freundlich, Temkin and Dubinin–Radushkevich models. Maximum adsorption capacities (31.09 and 34.63 mg/g) were achieved by ZnO–NPs and Alg–ZnO, respectively at 25 °C. The results of isotherm models indicate the perfect applicability of Langmuir and Dubinin–Radushkevich models, revealing the dominance of monolayer and the physisorption of chromium ions onto the studied adsorbents. [ABSTRACT FROM AUTHOR]

Plastic waste has become a pervasive and global threat to every ecosystem, and the continuous surge in plastic production has triggered the need for sustainable alternatives. This study focuses on harnessing a hundred percent biodegradable composite sheets with a natural crosslinker, which can be used in several end applications like seedling trays, gardening pots, sampling trays, one-time plates, ear and nasal swabs, etc. The proposed composite is manufactured with all-natural ingredients and zero harmful chemicals. The waste Kibisu silk or filature silk fibre (Bombyx mori) is used here as the fibre reinforcement, and wheat gluten (WG) is used as the matrix material. For plasticising and crosslinking the WG, castor oil and fresh lemon extract (Citrus limon) are used. In addition, pellets of sodium hydroxide are also added as a dispersion agent for WG. All the significant constituents used here are industrial waste or abundantly available in nature. The properties obtained from the characterisation processes indicate that natural crosslinker adds better physio-chemical properties in the developed samples. [ABSTRACT FROM AUTHOR]

The development of novel polymeric composites, especially those based on conductive polymers has attracted a considerable attention due to their applications in a wide range of fields. This study focuses on one of these biocomposites based on polyaniline Pani and a biopolymer (microcrystalline cellulose MCC), synthesized by in-situ polymerization of aniline using ammonium persulfate (APS) as oxidant at room temperature. Firstly, different amounts of MCC were dispersed in HCl solution with aniline monomer under stirring. Then a mixture of APS/HCl solution was introduced into the first aniline-MCC-HCl mixture. The obtained materials as well as Pani and MCC were characterized using powder X-ray diffraction (XRD), Argon adsorption–desorption (BET/DFT), thermal analysis, fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Thus, a correlation between interesting structural/textural/morphological data of these materials will be established. The results confirm the formation of Polyaniline-MCC composite under well determined conditions which has a more compact homogeneous morphology and a higher thermal stability than those of Pani and MCC. Furthermore, these materials are used for the catalytic degradation of toxic anionic dye namely Methyl Orange (MO) from aqueous media under UV light irradiation. The optimum values were 0.1 g L− 1 of photocatalyst, 30 ppm of MO solution, and pH solution of 5.6, which allowed reaching 97% within 70 min with high stability after four continuous runs. The photodegradation kinetics of MO onto composite followed the pseudo-first order model. [ABSTRACT FROM AUTHOR]

In this study, a hazelnut shell (HS) filled semi-interpenetrating polymer networks (semi-IPN) biocomposite adsorbent with novel and different compositions was developed that will enable the removal of lead ions, which are commonly found in water, by adsorption reactions. The structural and morphological properties of the produced adsorbents were characterized by FT-IR, XRD, TGA, DSC, BET, FE-SEM, EDX, and zeta potential measurements, and the production mechanism of these adsorbents was discussed. The effects of parameters such as different adsorbent dosages, different heavy metal concentrations, type of adsorbent, contact time, pH, and temperature on the swelling abilities and adsorption properties of adsorbents were investigated in detail. It has been determined that the adsorbent, which exhibits optimum adsorption and swelling properties, is a biocomposite containing 5% by weight HS filler, and it has been observed that it can remove up to 85% of lead ions under different parameters and conditions. In addition, the adsorption behaviors of the produced biocomposites are discussed using isothermal, kinetic, and thermodynamic models. Moreover, studies have been carried out on the reusability of the adsorbent, and it has been observed that the adsorbent produced within the scope of the study is still usable even after four cycles. [ABSTRACT FROM AUTHOR]

The aim of this work was to improve mechanical properties of a biocomposite of polylactic acid (PLA) reinforcing with fibrillated methacrylate-silanized hemp fibre. The effect of hemp fibre on photo-oxidation and hydrolytic degradation of PLA was evaluated through a QUV accelerated weathering test. Incorporation of 20 mass% fibre filler into neat PLA matrix resulted in increased tensile and flexural modulus for 150% and 200%, respectively. The outdoor degradation of neat PLA and PLA biocomposites was simulated in a 30 days of QUV accelerated weathering test in accordance with ISO 11507 method B. Glass transition temperature (Tg) was periodically recorded to measure the rate of degradation. Differential scanning calorimetry (DSC) analysis indicated that the degradation rate of the PLA matrix of the biocomposites tended to decrease proportionally to exposure time. The statistical regression method revealed a linear relationship between ln(Mn) and lnTg (R2 = 0.96). The 20 mass% hemp/PLA biocomposite was mostly destroyed over neat PLA after 30 days. The rate of degradation tended to have a linear proportion with hemp content. The results of FTIR 13C-NMR analysis confirmed that the substantial degradation of hemp/PLA biocomposites was due to the lignin content of the hemp fibre. The sensitivity of the PLA biocomposite to UVB light and moisture absorption accelerated photo-oxidation and hydrolytic degradation to the lowest molecular weight of PLA. [ABSTRACT FROM AUTHOR]

This article speculated the physical, mechanical, tribological, and surface morphology of the coir filler-reinforced polymeric composite. The investigation has been carried out regarding different weight percentages (2.5%, 5%, 7.5%, 10% and 12.5%) of coir filler. Moreover, a novel framework for inferring the optimal reinforcement condition of coir in epoxy resin has also been proposed in the form of Schweizer–Sklar fuzzy TOmada de Decisão Interativa e Multicritério (TODIM) approach. The proposed framework is reliable as it does away with the expert's biased evaluations and gives due consideration to their risk appetite. The optimal reinforcement condition has been deduced with due consideration to tribological, tensile, flexural and fracture properties of the fabricated composites. Through the investigation, it has been observed that the polymeric composite fabricated using 5 wt.% coir filler yields the most favourable results with regard to the considered mechanical and tribological properties. [ABSTRACT FROM AUTHOR]

Foam-formed cellulose biocomposites are a promising technology for developing lightweight and sustainable packaging materials. In this work, we produce and characterize biocomposite foams based on methylcellulose (MC), cellulose fibers (CF), and lignin (LN). The results indicate that adding organosolv lignin to a foam prepared using MC and CF moderately increases Young's modulus, protects the foam from the growth of Escherichia coli bacteria, and improves the hydrophobicity of the foam surface. This article concludes that organosolv lignin enhances many properties of cellulose biocomposite foams that are required in applications such as insulation, packaging, and cushioning. The optimization of the foam composition offers research directions toward the upscaling of the material solution to the industrial scale. [ABSTRACT FROM AUTHOR]

Optimization of the print setting is important to achieve the desired product characteristics, which, in turn, reduce the effort of the manufacturer and the cost of production. Natural fiber reinforced PETG composites can be a potential 3D printing raw material for additive manufacturing of medical products like scaffolds, implants, prostheses, and orthoses. But the process parameters of this unique composite material need to be optimized for the fabrication of complex structures. Here, PETG-silk fibroin (PETG-SF) composites were printed by optimizing the process parameters based on single and multi-objective optimization techniques for responses such as minimum porosity, maximum dimensional accuracy, and maximum yield load. For accurate measurement of porosity and dimensional accuracy, micro-CT analysis was employed. Single objective optimization results indicate layer height and printing temperature as the highest contributing factor for maximum dimensional accuracy, maximum yield load, and for minimum porosity. Multi objective optimization result shows high temperature, low layer height, and low speed are the best settings for minimum porosity, maximum yield load, and maximum dimensional accuracy. Finally, the optimized parameters were used to print an organic shaped object to validate the results for the production of patient specific anatomically conformed prosthesis and implants. Altogether, our results show that the process parameters have a significant influence on the 3D printing of natural fiber reinforced composites and a complex structure can be effectively fabricated with the optimized parameter settings. [ABSTRACT FROM AUTHOR]

The mechanical properties of natural fibers, as used to produce sustainable biocomposites, vary significantly—both among different plant species and also within a single species. All plants, however, share a common microstructural fingerprint. They are built up by only a handful of constituents, most importantly cellulose. Through continuum micromechanics multiscale modeling, the mechanical behavior of cellulose nanofibrils is herein upscaled to the technical fiber level, considering 26 different commonly used plants. Model-predicted stiffness and elastic limit bounds, respectively, frame published experimental ones. This validates the model and corroborates that plant-specific physicochemical properties, such as microfibril angle and cellulose content, govern the mechanical fiber performance. [ABSTRACT FROM AUTHOR]

This study explores the possibility of developing a new class of hybrid particulate-filled biocomposites using wood flour and rice husk wastes as environmentally friendly additives to poly(lactic acid) (PLA) as matrix material. Samples were prepared with fillers of different concentrations (0, 2.5, 5, 7.5 and 10 wt %), while the ratio of wood flour and rice husk was fixed at 1:1 in all cases. The preparation of biocomposites was performed through extrusion using a twin-screw extruder. Subsequently, they were formed into specimens by injection molding. Mechanical, thermal, thermomechanical, and morphological properties were examined. The addition of natural waste particles resulted in a remarkable improvement both in tensile and flexural modulus; however at a cost of impact strength and tensile strength. Meanwhile, flexural stress at conventional strain values were barely affected by the presence of wood flour and rice husk. The SEM images confirmed that there is a limited interfacial adhesion between the components, which supports the results obtained during mechanical tests. Both the differential scanning calorimetry (DSC) and the dynamic mechanical analysis indicated that the glass transition temperature of PLA was not affected by the incorporation of filler particles; however, the crystalline structure was gradually altered with increasing filler loading according to the DSC. Additionally, the particles were observed acting as nucleating agents, thereby increasing the overall crystallinity of PLA. [ABSTRACT FROM AUTHOR]

Combating pollution caused by nondegradable thermoplastics is a significant challenge keeping in view of their marginal cost, mechanical strength and ease of use for the production of esthetic products. Only low-cost/waste natural fiber-reinforced composites provide a ray of hope for replacing the aforementioned composites, but these composites have significant limitations, including low mechanical strength and excessive water penetration. Varying the weight percentages of waste vetiver fiber, soy-based composites are fabricated and characterized in this study. The highest tensile and flexural strengths of the vetiver–soy composite are found as 49.78 MPa and 51.4 MPa, respectively. The fabricated composite is moderately hydrophobic in nature, as per the contact angle and water absorption studies. Post-soil burial degradation studies like weight loss, Fourier transform infra-red spectroscopy, and optical micrography revealed that produced composite is totally biodegradable in nature. As a result, vetiver–soy composite will be a viable replacement for plastic and plastic-based items majorly in sectors like auto mobile industry and packaging sector. [ABSTRACT FROM AUTHOR]

Epoxy biocomposites were prepared using acid-, base- and silane-treated novel Caryota urens natural fibres (CUFs). The primary aim of this research is to reveal a better surface treatment method to achieve improved mechanical, thermal and fatigue properties of Caryota fibre epoxy composite system. The composites were prepared using hand layup method and post cured at 120 °C for 48 h. The tensile, flexural and impact results show that the silane surface–treated Caryota urens fibre–reinforced epoxy composite possesses improved mechanical properties than the base- and acid-treated Caryota urens fibres in the epoxy composite. Similarly, the inter-laminar shear strength (ILSS) of silane-treated Caryota urens–reinforced epoxy composite gives the highest value of 28 MPa. The TGA shows a large mass loss for both acid- and base-treated Caryota urens epoxy composites whereas the silane-treated Caryota urens in epoxy composite retains the thermal stability. The fatigue behaviour of silane surface–modified Caryota urens epoxy composite shows the highest fatigue life cycle of 18,315 for 25% of maximum tensile stress. The SEM micrographs show improved adhesion for silane-treated CUF than those treated with acid and base. This Caryota urens fibre–reinforced epoxy composite could be used in automobile body parts, domestic appliances, defence products and lightweight mini-aircrafts. [ABSTRACT FROM AUTHOR]

Solid waste management is one of the major problems in the twenty-first century. Utilizations of the food/Agro waste materials are crucial to reduce the pollution from the environment. The development of sustainable and biodegradable biocomposites from these wastages is gaining much attention in the research fields. This paper deals with the consumption of corncob waste after the use of corn seeds to develop biocomposites. The biocomposites have been fabricated at five different particles size of corncob (425–500 µm, 325–400 µm, 225-300 µm, 125-200 µm and 25–100 µm) with epoxy matrix and characterized their physical, mechanical, thermal and tribology behaviour. The results analysed that the performances of developed biocomposites increased with reducing the particles sizes. CCF-5 bio-fillers recorded 23% higher crystallinity compared to CCF-1 that increased the interfacial interaction of reinforcements and reduced the water uptake capabilities. The mechanical performances of biocomposites like tensile strength (41.47 MPa), flexural strength (48.67 MPa), and hardness (46) have been examined maximum for CCH-4 while, tensile modulus (1.45GPa) and flexural modulus (3.35GPa) are maximum for CCH-5 biocomposites. The wear and friction behaviour of the developed biocomposites have been investigated by varying the applied load (10 N, 15 N, and 20 N) at dry and wet conditions using a pin on the disc wear testing machine. The CCH-4 biocomposites showed lowest volume loss and specific wear rate at every loading condition as well as high thermal stability with 28.168% of residual mass at 800 ºC. The addition of corncob bio-filler resulted in economical and cost-saving materials with improved mechanical properties and wear resistance compared to conventional materials. [ABSTRACT FROM AUTHOR]

Edible films and coatings are edible thin layers used as food coatings or barriers between foods and the environment. Biopolymers including polysaccharides, proteins or their mixture which used to produce edible films, are high potential as carriers of additives such as anti-microbial agents and antioxidants. Generally, the use of edible and biodegradable films has been limited due to their sensitivity to moisture and poor mechanical properties. On the other side, the use of a combination of polymers for film forming considered as an effective method to overcome mentioned limitations, so, the best functional properties of each compound can be used.This paper intended to investigate the ability of the mucilage from chia seeds in combination with gelatin to form a suitable composite film and produce a new type of biodegradable biopolymers used in food packaging. Chitosan nanoparticles used in four different levels (0, 2, 4 and 6%) as antimicrobial agent in the production of the films. Physicochemical and antimicrobial properties of the produced films were evaluated. Results shown that adding chitosan nanoparticles in different percentages caused significant changes in water vapor permeability (0.129- 256), opacity (0.656–6.185), ΔE colorimetric factor (5.570–4.736) and antimicrobial properties against gram-positive microorganisms (S. aureus) (1-21.666 mm) (p < 0.05). Furthermore, the microbial tests indicated a greater inhibitory effect of chitosan nanoparticles against gram-positive bacteria (max for gram positive = 21.666 mm vs. max for gram negative = 12.333 mm). In conclusion, development of the environmental friendly food packaging such as bio-composite or nanobiocomposite ones reduces the negative impacts of packaging on the environment. Although nanocomposites are an improved form of biopolymers, they still have some deficiencies compared to synthetic polymers that limit their use. To overcome these drawbacks, various agricultural and food-based materials should be considered and evaluated for their potential application in the packaging industry. [ABSTRACT FROM AUTHOR]

Wood waste from construction sites represents an environmental and financial burden. Furthermore, there is a need in everyday practice to replace CO2-intensive construction materials and especially Portland cement, with less polluting alternatives such as slag, metakaolin, hydraulic and non-hydraulic lime, or magnesium cement, among many others. In this scenario, an eco-friendly insulator made of recycled wood chips embedded in a lime-metakaolin binder was proposed and assessed for application in the construction industry. The influence of curing regimes on carbonation, microstructure, compressive and flexural strength, density, and thermal conductivity was studied. Specimens were cured in three subsequent environments of variable duration: (i) under a plastic sheet with high moisture content, (ii) exposed to drying in standard lab conditions and, (iii) in a CO2 incubator. Pre-conditioning of the specimens before the CO2 curing, affected the carbonation efficiency and subsequently microstructure and mechanical properties of the biocomposite. Carbonation rate (from different curing regimes) affected mechanical properties also when comparing fully carbonated specimens, leading to different engineering properties of the biocomposite. Density and thermal conductivity were less impacted overall. [ABSTRACT FROM AUTHOR]

Metal oxides with distinct properties can be integrated into a cellulose matrix, providing a promising approach to improve the performance of cellulose materials and expand their applications in photocatalysis. This research focuses on the development of a new biomaterial by incorporating hematite (α-Fe2O3) into the crushed leaves of the palm tree Washingtonia filifera, both in their raw form and as cellulose extracted from the same plant. The incorporation of α-Fe2O3 was carried out hydrothermally. The palm leaves, extracted cellulose and synthesized composites were characterized by thermal analysis (TG) and FT-IR spectroscopy. FT-IR spectra revealed peaks at 524 and 449 cm−1 in the synthesized material, attributed to the vibrational deformation of the Fe–O bond. In contrast to the TG profile of raw palm leaves, the thermogram of the composite showed single-step degradation at 343 °C, indicating chemical modification of the cellulose matrix and successful incorporation of hematite into lignocellulose. The SEM image showed that the grains of α-Fe2O3 are homogeneously incorporated in the matrix. The second part of the study examines hematite (α-Fe2O3) functioning as a sensitizer. It was characterized optically with a gap Eg of 1.94 eV and electrochemically, with a flat band potential of − 0.45 VSCE. The conduction band (− 0.65 VSCE) is more cathodic than the O2/O2•− level. As an application, the prepared materials were effectively tested in the photocatalytic degradation of Rhodamine B (Rh B, 10 ppm). A reduction of 60% was reached under visible irradiation (23 mW cm−2). [ABSTRACT FROM AUTHOR]

Heren, chitosan (CH), algae (AL), and montmorillonite clay K10 (MK10) were used in the hydrothermal synthesis of a new Schiff-base system of glutaraldehyde-crosslinked chitosan-based biocomposite (CH-AL-MK10/GL) for the removal of a model cationic dye [MV (2B)] from aqueous environments. Various analytical methods were employed to evaluate the characteristics of the synthesized biocomposite (e.g., BET surface analysis method, elemental analysis, FTIR, SEM–EDX, XRD, and point of zero charge). The key adsorption parameters (CH-AL-MK10/GL dose, pH, and time) were optimized using the BBD model and the optimum adsorption (%) value of 86.4% was achieved at the following operating conditions: CH-AL-MK10/GL dose: 0.99 g/100 mL, pH: 8.3, time: 418 min and a quadratic model was generated for predicting the dye removal values based on the adsorption conditions. The adsorption equilibrium data revealed great compatibility with the pseudo-second order kinetic model and Langmuir and Freundlich isotherm models, achieving a maximum adsorption capacity of 98.3 mg/g at 25 °C. Hence, the adsorption of MV (2B) by CH-AL-MK10/GL was through chemisorption in an initially monolayered fashion which then proceeds to a multilayered model after the surface layer reaches a saturated state. The results of all the characterization methods as well as the adsorption equilibrium studies were utilized to determine the possible interactions between the CH-AL-MK10/GL surface and MV (2B) dye molecules and the electrostatic forces, hydrogen bonding, Yoshida hydrogen bonding and n- π stacking interactions were concluded to be responsible for the adsorption process. [ABSTRACT FROM AUTHOR]

This study deals with the modification of a predominantly amorphous poly(lactic acid) (PLA) by blending it with a semi-crystalline biopolymer, polyhydroxybutyrate-co-valerate (PHBV), which has a high crystallinity. The blends with different concentrations of PLA and PHBV were compounded with spent coffee grounds (SCGs) and processed by injection moulding. The structural, thermal and mechanical properties of the produced samples were investigated. Particular attention was paid to the effect of the presence of SCG and the concentration of PHBV in the blend on the crystallization kinetics and the heat deflection temperature (HDT). For equimolar blends, only a slight increase in HDT (about 5 °C) was observed, but the addition of PHBV suppressed the cold crystallization of PLA, which otherwise negatively affects the dimensional stability of injection moulded parts. A similar effect, but to a lesser extent, was achieved by adding SCG to the PLA matrix. Thus, it is clear that the material structures of PLA/PHBV blends and composites help to minimize additional shrinkage of the parts and increase their dimensional stability. Due to the co-continuous structure of the symmetric PLA/PHBV blends and the increase in the degree of crystallinity from 36 to 47% by annealing the produced samples, the heat deflection temperature increased from 65 up to 90 °C. [ABSTRACT FROM AUTHOR]