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Polymer technology has rapidly advanced across diverse domains, particularly in biomedical applications. Among various polymers, polyurethane (PU) hold great potential in developing biomaterials such as biomedical scaffold and drug delivery. In this study, we have innovatively engineered eco‐friendly polyurethane using lignin, a sustainable bio‐polyol derived from oil palm empty fruit bunches. To enhance the physicochemical properties of the PU, we have incorporated hydroxyapatite (HA) into the composites. The inclusion of HA has led to notable improvements in crucial properties such as density, porosity, and water absorption, making these composites ideal candidates for tissue regeneration scaffolds. Furthermore, to assess their biomedical applicability in drug delivery and cell scaffolding, we have employed the quercetin drug model. The results revealed a sustained kinetic release behavior within the polyurethane/hydroxyapatite (PU/HA) composites, showcasing their potential for controlled drug delivery applications. Moreover, cytotoxicity assays conducted using neuro‐2a cell models demonstrated the non‐cytotoxic nature of both PU and PU/HA composites. This finding holds significant implications for biomedical applications, indicating that these composites offer biocompatible platforms for tissue engineering and regenerative medicine endeavors. The ability of these composites to support cell viability underscores their potential for a wide range of biomedical applications, including neural tissue engineering and drug delivery systems targeting brain diseases. These findings pave the way for the development of innovative and sustainable biomaterials with diverse biomedical applications. Highlights: An eco‐friendly polyurethane has been engineered by harnessing liginin‐derived oil palm empty fruit bunches.Incorporation of hydroxyapaptite enhance the physical properties of polyurethane.Controlled kinetic drug release is one of polyurethane/hydroxyapatite (PU/HA) composites features.The PU/HA composites has low cytotoxicity against neuro‐2a cells. [ABSTRACT FROM AUTHOR]

An efficient method to accelerate the use of polymer composites is to focus on their development as environmentally friendly materials that can naturally break down without causing any harm to the ecosystem. Hence, the primary aim of this study is to develop a biocomposite material through the fusion of Sesbania rostrata (SRF) bark fibers and the polycaprolactone (PCL) biopolymer. Various percentages (10, 15, 20, and 25 wt.%) of untreated and sodium bicarbonate‐treated SRF were incorporated into polycaprolactone to create the biocomposite samples. The composite panels were made using the compressing molding technique. Several tests were performed on the samples, such as mechanical, thermal, water absorption, wear, and morphological tests. Research has demonstrated that the strength of biocomposites composed of 20% chemically treated SRF and PCL is superior to that of other mixed materials. The thermal properties of the biocomposite remained unchanged when untreated fibers were included, but they improved when treated fibers were included. Higher water absorption properties are attributed to an increased fiber volume fraction in the biocomposites, while chemically treated fibers exhibit a notable improvement in water resistance. The wear test results indicate that the weight loss of the biocomposites is mainly influenced by the contact temperature and adhesion between the SRF surface and the PCL matrix. When examining the fractured biocomposites with a scanning electron microscope (SEM), it becomes evident that the primary reasons for failure are fiber pull‐out, debonding, and agglomeration. Highlights: SR Natural fiber is chemically treated by eco‐friendly sodium bicarbonate.The treated SRF‐reinforced composites had best mechanical property.The treated SRF‐reinforced composites showed less water absorption.The composite mechanical and thermal properties had dropdown at 25 wt.% SRF.The addition of SRF reduced the weight loss of composites on wear test. [ABSTRACT FROM AUTHOR]

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. Highlights: 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]

The effects of random dislocations on the vibrational properties of finite-length RNA and DNA macro-structures have been investigated by means of a harmonic Hamiltonian and the Green's function method. The RNA molecule has been modeled using a half ladder model, and three models (a fishbone model and two different strand models) have been employed to model the structure of DNA. The lengths of the finite and cyclic systems are gradually increased to more accurately approximate the structures of RNA and DNA. Springs whose behaviors are governed by Hooke's constitutive law have been used to represent the bonds between the masses, with the stiffness of the vertical springs randomly changing along the length of each model. This results in a more realistic representation of the inherent randomness of the studied structures. To investigate the effect of random dislocations on the mechanical response of the studied systems, it has been assumed that a random mass-spring ensemble has been knocked out of place by an external force. It has been found that increasing the number of building blocks along the length of the models suppresses the influence of dislocations on the vibration spectra of RNA and DNA. It was also observed that at low frequencies, the influence of dislocations becomes more pronounced. Besides, taking into account the collective mass of the sugar-phosphate backbone results in the appearance of gaps in the vibration spectra. By introducing dislocations into the models, additional dislocation-induced vibrational states appear in the DOS curves. What stands out from the results is that the responses of the studied systems to these changes are strictly nonlinear. The employed methodology can be applied to investigate the mechanical response of damaged RNA and DNA. [ABSTRACT FROM AUTHOR]

As dental pulp contains the stem cells necessary for regeneration, the tooth should hold the intrinsic capacity for self-repair. A triphasic hybrid dental biocomposite (3HB) composed of biocompatible biopolymers to provide strength, antibacterial properties and protein-based cell support could provide a conducive microenvironment for the regeneration of dental structures. 3HB was incorporated into Mineral Trioxide Aggregate (ProRoot MTA) to construct a malleable injectable implant. Human tooth pulp cells (hDPCs) significantly increased proliferation in the presence of 3HB+MTA compared to 3HB or MTA alone. Cell viability decreased with MTA alone but increased with 3HB and 3HB+MTA. 3HB+MTA was implanted into the residual tooth of drilled Wistar rat M2 molars for up to 45 days. Stereological analysis from micro-CT images showed the volume of the tooth remaining. Histologically, regenerative pulpal architecture was seen invading 3HB. A continuous odontoblastic profile lined a deposit of dentin-like material suggesting reparative dentinogenesis. Overall, no infection or encapsulation was seen. Immunohistochemically, odontoblasts were seen along the margins of the wounded tooth undergoing repair. Mesenchymal cells (MSCs) were seen at the base of the drilled tooth and by 21 days had translocated into the implant itself. Cells stimulating remineralization were highly expressed in the tooth undergoing repair. CD146-positive MSCs were seen in the center of the implant, possibly stimulating remineralization. In conclusion, behavior of 3HB+ in vitro and in vivo provided a promising start as 3HB+MTA may serve as a viable regenerative scaffold for pulp regeneration; however, this should be further studied before clinical use can be considered. [ABSTRACT FROM AUTHOR]

This paper investigates the dissolution of two biopolymers, cellulose and silk fibroin, in a mixture of 1-ethyl-3-methylimidazolium acetate (EmimAc) and dimethyl sulphoxide (DMSO). EmimAc is a promising environmentally friendly solvent currently in wide use but can be limited by its high viscosity, which inhibits the speed of dissolution. To mediate this, DMSO has been used as a cosolvent and has been shown to significantly lower the solution viscosity and aid mass transport. Dissolution experiments are carried out separately for both cellulose and silk fibrion with a range of EmimAc:DMSO ratios from 100 wt% EmimAc to 100 wt% DMSO. Interestingly, the optimal EmimAc:DMSO ratio (in terms of dissolution speed) is found to be very different for the two biopolymers. For cellulose, a mixture of 20 wt% EmimAc with 80 wt% DMSO is found to have the fastest dissolution speed, while for silk fibroin, a ratio of 80 wt% EmimAc with 20 wt% DMSO proves the fastest. These dissolution trials are complemented by rheological and nuclear magnetic resonance experiments to provide further insight into the underlying mechanisms. Finally, we produce hybrid biopolymer films from a solution to show how this work provides a foundation for future effective dissolution and the preparation of hybrid biopolymer films and hybrid biocomposites. [ABSTRACT FROM AUTHOR]

This study investigates lignocellulosic biocomposites' physicochemical properties and strength parameters with varying thermoplastic content. Biocomposites were prepared using wood (Pinus sylvestris) or hemp shives (Cannabis sativa L.) combined with 25% and 50% ABS regranulate. The research focused on evaluating the mechanical energy consumption during the compaction of wood-ABS biocomposites with different pine fractions pretreated with hot water extraction (HWE) and analyzing the relationship between strength and thermoplastic content. Results indicate that the composition of the mixture and the size of the hemp shives fraction did not significantly influence energy consumption during densification. Energy values ranged from 1.234 × 10⁻8 J to 8.296 × 10⁻8 J. While the densification of pine after HWE was unsuccessful without ABS, preheating the mixtures with ABS facilitated the production of a uniform composite. The work required for densification ranged from 1.404 × 10⁻5 J to 2.711 × 10⁻5 J for fractions without ABS. For mixtures with ABS, the work required was 1.954 × 10⁻5 J for fraction 0 ÷ 0.4 (f1) and 0.042 × 10⁻5 J for fraction 0.4 ÷ 0.8. [ABSTRACT FROM AUTHOR]

Polylactic acid (PLA) composites reinforced with 10 wt% of flax (FF) or bamboo (BF) fibers were prepared via an internal mixer and/or twin-screw extrusion. Alkali pretreated fibers were soaked in silane to improve adhesion between fibers and matrix. 0.8 wt% of Joncryl™, a grafted copolymer acting as PLA chain extender, was also used alone or in combination with silane treatment of fibers to improve interfacial adhesion. The influence of silane treatment and/or Joncryl on the composite materials on mechanical, thermal and thermomechanical properties of materials processed through injection molding was investigated. Improved adhesion of the fibers to the matrix was shown using a scanning electron microscope. Fourier Transform Infrared Spectroscopy indicated that chemical bonds were formed between the silane coupling agent and fibers. X-ray Photo-electron Spectroscopy confirmed that fibers and silane derivatives were effectively coupled. XPS also highlighted that silane coupling agent reacted in higher amounts on bamboo than flax fibers, probably due to a higher amount of lignin in the case of bamboo fibers. Thermogravimetric analyses indicated that silane-treated flax and bamboo increased the thermal stability of the corresponding composites (PLA-SFF and PLA-SFB) compared to non-treated fiber composites. The incorporation of Joncryl alone entailed a degradation of the thermal stability of the corresponding composites (PLAJ-FF and PLAJ-FB) but enhanced the PLA/fibers interfacial adhesion. The combination of Joncryl and silane treatment resulted in strong improvements of thermal stability and interfacial adhesion for the PLAJ-SFF and PLAJ-SBF composites. Increase in tensile moduli and decrease in tensile strengths with the incorporation of the pristine fibers were noted. For silane-treated fibers, the tensile modulus and the strength of the corresponding composites were improved when adding Joncryl alone or in combination with silane. From also rheological and molar weight measurements, it could be concluded that Joncryl acts both as PLA chain extender and coupling agent. [ABSTRACT FROM AUTHOR]

In this work, short oil palm fibre-reinforced bio-epoxy matrix composites were fabricated using the hand-lay-up technique. The effects of oil palm fibre composites on mechanical, physical, and thermal behaviours were examined. This work aimed to identify the optimal fibre loading that enables the oil palm/bio-epoxy composite to have superior thermal and mechanical properties. Fibre loading varied from 30 to 60 wt%. A maximum Young's modulus of 5.76 GPa was obtained at 60 wt% while a maximum flexural modulus of 5.2 GPa and impact strength of 5.55 kJ/m2 was obtained at 50 wt%. However, tensile and flexural strength were not much improved. Regarding the moisture absorption and thickness swelling, the composites followed a similar order: bio-epoxy matrix < 30 wt% < 40 wt% <50 wt% < 60 wt%. The fickian diffusion model was used to describe the thickness swelling behaviour. The major inference from the thermal characterization was that as the fibre loading was increased, there was a substantial improvement in thermal stability evident from the lower damping factor (0.21 at 60 wt.%), better dimensional stability and higher residue % (22.22% at 50 wt%) at elevated temperatures. Besides, scanning electron microscopy (SEM) was examined for tested samples to understand the fibre-to-matrix bonding phenomenon. Based on these results, the short oil palm fibre composites can be suggested for some potential applications such as automotive components (e.g., door trims, interior panels), aerospace (e.g., tray tables, overhead bins) and construction materials (e.g., cladding, roofing). [ABSTRACT FROM AUTHOR]

The present work aimed to study the printability and tensile behaviors of ramie yarn‐reinforced PLA‐based composites fabricated by an in situ impregnated fused filament fabrication (FFF) process. The dimensional error analysis was conducted to evaluate the printability of biocomposites with different processing variations and continuous ramie yarns. The effect of yarn volume fraction (Yf) caused by processing variations and ramie yarn characteristics on the mechanical properties was also studied. The results showed that the dimensional accuracy of the biocomposites with different ramie yarns could be adjusted by process parameter optimization. On the basis of ensuring printability, the Yf was within the range of 6.80% to 23.32% in the current study. With the increase of Yf, the tensile strength and the tensile modulus of the biocomposites significantly increased. When the Yf was 23.32%, the tensile strength and the tensile modulus increased by 60.78% and 382.35%, respectively, compared to pristine PLA. In addition, an analytical model considering the influences of Yf and microstructural characteristics such as interfacial void content (Vp) on the tensile strength of the 3D printed biocomposites was derived, and the theoretical predictions were in good agreement with experimental measurements. [ABSTRACT FROM AUTHOR]

This study aims to develop a recyclable, economical, and flame-retardant composite material using polypropylene, beech flour, tetrabromobisphenol A bis (TBBPA), and antimony trioxide (ATO). Flame-retardant additives (TBBPA and ATO) were initially added into polypropylene at different rates, and masterbatch (MB) samples were produced by the extrusion method. Subsequently, different percentages of wood flour (10%, 15%, 20%, 25%, and 30%) along with 60% MB were added to the polypropylene to create wood–polymer composites (WPC) using the injection method. The TBBPA, ATO, and wood flour were introduced through side-feeding hoppers during injection to ensure a homogeneous distribution within the WPC. Physical, thermal, and mechanical tests were conducted on the WPC samples. Additionally, TGA, FTIR, and SEM analyses were performed. The results indicated that the optimal ratios for TBBPA and ATO additives were 20% and 10%, respectively. It was observed that increasing the wood flour content in the WPC samples led to enhanced density, water absorption, hardness, impact, and abrasion resistance. Conversely, MFI, bending strength, and tensile strength decreased with higher wood flour content. It was observed that WPC samples exhibited flame resistance up to 725 °C. The produced WPC materials can be used in flooring applications, interior furniture, decorative wall panels, and aesthetic structural elements due to their fire behavior, good mechanical properties, low water-absorption rates, and aesthetic appearance. [ABSTRACT FROM AUTHOR]

Highlights This work investigates the construction of biodegradable packaging film based on polylactic acid (PLA) reinforced with a novel antibacterial hybrid nanofiller to improve barrier and mechanical properties. The study focuses on incorporating silver‐ingrained silica particles (Ag–In–Si) into PLA matrix to prepare the packaging film (Ag–In–SiPLA) that has superior antibacterial, and barrier property with negligible oxygen and water vapour penetration. The Ag was synthesized using natural neem leaf extract as a reducing agent. To ingrain silver over rice husk silica (Si) an in situ technique was adopted. Hence called Ag‐In‐Si bio‐filler. The Ag–In–SiPLA films were fabricated using melt blending and sheet extrusion methods by means of a micro‐compounder. The addition of rice husk silica served the purpose of cost‐effectiveness of the packaging film along with the enhancement of the oxygen and water barrier properties of the films. The optimized sample (PLA loaded with 3% Ag–In–Si), exhibited optimum transparency, moisture resistance, and barrier properties compared with control PLA film. The experiments on Muntingia calabura (Jamaica cherry) preservation have verified the remarkable effectiveness of Ag–In–SiPLA films in preserving their quality for an extended period. These biodegradable packaging films, composed of food‐grade materials and sustainable ingredients, have the potential to provide a compostable and environmentally friendly solution for various packaging applications. This research shed light on the antibacterial Ag–In–SiPLA film as a long‐term, high‐performance fruit packaging solution. Novel antibacterial PLA composite with enhanced barrier and mechanical properties. Silver‐ingrained silica particles improve antibacterial and barrier properties. Green synthesis of silver using neem leaf extract Melt blending and sheet extrusion used to create cost‐effective packaging films. Ag–In–SiPLA films extend Muntingia calabura preservation, proving effective. [ABSTRACT FROM AUTHOR]

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. Highlights: 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]

Background: medical teams continue to face challenges with infections following hip replacement surgery, whether they occur shortly after the procedure or months or years later. Certain medical conditions like diabetes, rheumatoid arthritis, and obesity are risk factors that make patients more susceptible to infections. Traditional intervention methods such as DAIR, one-step, or two-step procedures are being enhanced and refined to ensure quicker and more effective treatment. Some cases present particularly difficult challenges, featuring persistent fistulas and unpredictable responses to treatment. Methods: in our article, we share two unique cases, detailing their histories, progressions, and treatment decisions. We explore the use of antibiotic-impregnated calcium biocomposite as a local adjuvant therapy and the application of negative pressure therapy to expedite healing. The system of NWPT has seen widespread uptake and is now implemented routinely for open wounds, such as open fractures, fasciotomies, ulcers, and infected wounds. Results: our findings demonstrate that surgical debridement and calcium sulfate bead insertion successfully treat bone and joint infections without causing any side effects or complications. As a particularity, in the first case, we encountered the exteriorization of Stimulan pearls after surgery, without other complications related to the biocomposite. Conclusions: we have found that NPWT is a beneficial tool in managing complex wounds in both acute and chronic stages, after the infection is cured, reducing the need for frequent dressing changes, shortening hospital stays, and enhancing patient comfort. [ABSTRACT FROM AUTHOR]

The current research is devoted to the development and characterization of green antimicrobial polymer biocomposites for food packaging applications. The biocomposites were developed by melt compounding on the basis of two different succinate polymer matrices with varying chain stiffness—polybutylene succinate (PBS) or its copolymer with 20 mol.% of polybutylene adipate (PBSA). Fungi chitosan oligosaccharide (C98) and crustacean chitosan (C95) were used as antimicrobial additives. The rheological properties of the developed biocomposites were determined to clear out the most suitable temperature for melt processing. In addition, mechanical, thermal, barrier and antimicrobial properties of the developed biocomposites were determined. The results of the investigation revealed that PBSA composites with 7 wt% and 10 wt% of the C98 additive were more suitable for the development of green packaging films because of their higher ultimate elongation values, better damping properties as well as their superior anti-microbial behavior. However, due to the lower thermal stability of the C98 additive as well as PBSA, the melt processing temperatures of the composites desirably should not exceed 120 °C. Additionally, by considering decreased moisture vapor barrier properties, it is recommended to perform further modifications of the PBSA-C98 composites through an addition of a nanoclay additive due to its excellent barrier properties and thermal stability. [ABSTRACT FROM AUTHOR]

Skin wounds, due to their high vulnerability to infections, represent a significant public health issue. These wounds are not only disabling but also entail costly treatments and slow recovery. Consequently, it is crucial to implement new treatments based on bioactive and natural antimicrobial compounds utilizing fibers, polymers, hydrocolloids, and hydrogels to control potential infections and promote wound healing. This study aimed to develop a biocomposite with antimicrobial activity for the treatment of skin wounds, using sodium alginate, bamboo fiber, and a natural antimicrobial as ingredients. The physico-mechanical properties (Young's modulus, tensile strength, elongation at break, moisture absorption, and water vapor permeability) and antimicrobial activity against Escherichia coli, Staphylococcus aureus, and Staphylococcus hominis were determined. The results demonstrated that the designed biocomposite possesses adequate physico-mechanical properties, such as flexibility, strength, and water absorption capacity, in addition to exhibiting antibacterial activity, making it suitable to be used as a dressing in wound treatment. [ABSTRACT FROM AUTHOR]

This study deals with the preparation of a novel biomaterial by incorporating the hematite α-Fe2O3 onto crushed leaves of the Washingtonia filifera palm tree in their raw state and in extracted cellulose from the same plant. The incorporation of α-Fe2O3 was accomplished by hydrothermal route at 200 °C. The palm leaves, extracted cellulose, and synthesized products were characterized by thermal analysis (TG) and FT-IR spectroscopy. The latter revealed peaks at 524 and 449 cm−1 for the synthesized material, attributed to vibrational deformation of the inorganic Fe-O bond. In contrast to the TG profile of raw palm leaves, the thermogram of the composite degrades in a single step at 343 °C. This one-step decomposition clearly indicates the chemical modification of our cellulose matrix and confirms the successful incorporation of the hematite α-Fe2O3 into the lignocellulose. The second part is devoted to α-Fe2O3 working as sensitizer in photocatalysis, it was characterized optically (Eg= 1.94 eV) and electrochemically with a flat band potential of −0.53 VSCE. The conduction band (−0.73 VSCE) is more cathodic than the potential of the O2/O2•− couple (−0.52 VSCE) and should reduce dissolved oxygen into reactive O2•− radical. The as-prepared materials were successfully tested in the photocatalytic degradation of Rh B (10 ppm) and the result gave an abatement of 60% on α-Fe2O3/lignocellulose under visible light irradiation (LED lamp) with a flux of 23 mW cm−2. The kinetic obeys a first-order model with a half photocatalytic-life of ∼ 7 h. [ABSTRACT FROM AUTHOR]

Starch-based coating systems find application in different industrial sectors as eco-friendly carriers of bioactive compounds such as in fertilizers and seeds. However, starch cannot be used as the only matrix component because of its high hygroscopicity and poor mechanical qualities. Here, we investigated the effects of the sequential addition of maltodextrin, cellulose, glycerol, and bentonite on the physicochemical characteristics of starch-based films potentially applied in coating systems. It observed that the addition of bentonite tends to increase hydrophobicity, but association with glycerol contributed to its reduction. The sequential reduction in water vapor permeability was observed, achieving lower values with the addition of bentonite. Viscosity variation was also verified, still in gel form. The matrices with or without glycerol showed a significant increase in viscosity with the addition of bentonite. The adjustment of this parameter is essential in the coating system. This trend is also observed for mechanical properties. In this case, cellulose addition provided a remarkable variation. Additionally, the water content between the starch chains is considerably reduced, as well as the brittleness and uniformity are improved with the simultaneous addition of fillers and glycerol-containing matrices. [ABSTRACT FROM AUTHOR]

The exceptional film-forming ability, biodegradability, biocompatibility, and wide availability of cross-linked gelatin have sparked considerable interest in its utilization for packaging purposes. APTES (3-Aminopropyltriethoxysilane) cross-linker is preferred due to its ability to bind with gelatin involving its silanol groups and for its non-hazardous nature. This study aims to fabricate cross-linked gelatin films specifically tailored for packaging applications. The FTIR spectra of the gelatin films provided evidence of successful cross-linking, as indicated by the presence of Si–O-Si and Si–OH bonds. SEM analysis exhibited structural uniformity with increasing concentrations of the cross-linker, indicating favorable interactions between APTES and gelatin molecules. Furthermore, enhanced thermal stability was observed, as evidenced by TGA results, suggesting the formation of stable cross-links. The introduction of APTES to the gelatin films preserved their transparency, reduced solubility (from 84 to 58%), lowered water permeability, and increased tensile strength up to 7.3 MPa with the increase in film thickness from 0.129 mm to 0.150 mm. Moreover, the films exhibited decreased transmission of UV light (reduced from 4.8 to 1.4% by adding APTES in the 280 nm wavelength), indicating potential applications in UV protection. Finally, the cross-linked gelatin films modified with APTES demonstrated favorable characteristics for packaging applications. [ABSTRACT FROM AUTHOR]

In this work, natural fibers extracted from the medicinal aromatic plant Deverra tortuosa, with different sizes (S1 = 2 mm and S2 = 500 μm), were incorporated into recycled low density polyethylene (rLDPE) to produce sustainable biocomposites. Compounding was performed with different fiber concentrations (0 to 30% wt.) via twin-screw extrusion followed by injection molding. Based on the samples obtained, a comprehensive series of characterization was conducted, encompassing morphological and mechanical (flexural, tensile, hardness, and impact) properties. Additionally, thermal properties were assessed via differential scanning calorimetry (DSC), while Fourier transform infrared spectroscopy (FTIR) was used to elucidate potential chemical interactions and changes with processing. Across the range of conditions investigated, substantial improvements were observed in the rLDPE properties, in particular for the tensile modulus (23% for S1 and 104% for S2), flexural modulus (47% for S1 and 61% for S2), and flexural strength (31% for S1 and 65% for S2). Nevertheless, the tensile strength decreased (15% for S1 and 46% for S2) due to poor fiber–matrix interfacial adhesion. These preliminary results can be used for further development in sustainable packaging materials. [ABSTRACT FROM AUTHOR]

Cellulose nanofibers (CNFs) have been widely studied for their reinforcing potential in high-performance composites. While there are numerous publications on CNF-reinforced composites in a variety of polymer matrices, few have considered the recyclability of such thermoplastic composites and whether the incorporation of CNFs deteriorates or improves their performance upon reprocessing. In this study, two thermoplastic resins, poly(lactic acid) (PLA), and glycol-modified polyethylene terephthalate (PETg), were prepared with CNF reinforcement and thermomechanically recycled to investigate the effect of CNF inclusion on the composite properties after reprocessing as well as their effect on the composites' number of useful life cycles. Changes in mechanical, thermal, rheological, molecular, and microstructural properties of the composites and/or base resins were monitored as a function of cycle numbers. As is typical, the polymers' molecular weight and mechanical performance deteriorated with continued processing. However, the addition of spray dried CNF was found to better maintain the mechanical performance of both polymers throughout multiple recycling steps as compared to neat samples. For example, the tensile strength of PETg with 20 wt% CNF after 6 processing cycles was found to exceed that of virgin neat PETg, and higher loadings of CNF were found to preserve a higher yield strength during multiple rounds of reprocessing compared to PETg composites with lower CNF loadings. Ultimately this study indicates that the addition of CNF to some thermoplastic materials can increase both their sustainability by offsetting the use of high-embodied energy resins and their circularity by enabling performance retention over more use cycles. [ABSTRACT FROM AUTHOR]

Accelerating climate change poses an alarming global issue, demanding a range of prompt and effective solutions. In response, bio-based plastics and biocomposites have emerged as extensively researched alternatives to combat the environmental threats posed by a warming climate. In this context, the present paper presents a cradle-to-gate life cycle assessment of a newly developed polyamide-starch biocomposite, with varying content of potato starch as the biofiller (ranging from 0 to 70 wt%). The primary aim was to quantitatively measure the total carbon footprint of the selected biocomposite. The results indicated that the progressive addition of potato starch as the biofiller into the copolyamide matrix significantly reduced the total carbon footprint of the biocomposite, achieving a maximum reduction of 42–43% with the highest starch content of 70 wt%. Moreover, the newly developed polyamide-starch biocomposite demonstrated excellent performance compared to reference fossil-based polyamides of polyamide 6 (PA6), polyamide 12 (PA12), and polyamide 6.6 (PA6.6), as well as composites of PA610/80 wt% polylactic acid modified by reactive extrusion (REX-PLA) and PA40/30 wt% glass fibers, with carbon footprint reductions of 29, 39, 42, 59, and 79%, respectively. Based on these findings, the polyamide-starch biocomposite, especially with the highest content of potato starch (70 wt%), exhibits significant potential as a new material solution to reduce the carbon footprint of several existing fossil- and bio-based polyamides together with polyamide-based composites. In doing so, it contributes to advancing the development of a more climate-friendly future for plastics through reductions in their carbon footprints. [ABSTRACT FROM AUTHOR]

This work presents a novel process for production of additive-free wood composites by ionic liquid treatment of wood powder involving extraction of lignin followed by precipitation onto particle surfaces, and hot pressing to form a cellulose-reinforced lignin biocomposite. Physicochemical properties of lignin-coated wood powders, as well as their degree of fusion upon hot pressing, were evaluated with the aim of optimising ionic liquid treatment and hot-pressing conditions. Optimal conditions to achieve complete fusion while minimising process energy demand were determined using response surface methodology, and mechanisms of process parameter effects investigated using gas pycnometry, electron microscopy, image analysis, thermogravimetry, and calorimetry. These novel materials, derived solely from waste with only reusable reagents, represent a sustainable alternative to existing engineered wood products, which rely on petrochemical additives that release toxic volatile compounds, offering a means to reduce environmental and health hazards associated with production and use of composites from wood waste. [ABSTRACT FROM AUTHOR]

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]

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]

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]

In this research, biodegradable Chitosan–Nano-Cellulose–Nisin (CH-NC-N) film was synthesized and utilized for antibacterial application in medicine and food packaging. The antibacterial chitosan–nano-cellulose–nisin film was characterized using various techniques such as mechanical and physical properties analysis, Scanning Electron Microscopy (SEM), X-Ray Diffraction (XRD), and Fourier Transform Infrared Spectroscopy (FTIR) techniques. The film ’ s ability to inhibit growth of pathogenic bacteria including Escherichia coli, Escherichia coli XDR, Klebsiella pneumonia XDR, Listeria monocytogenes, and Staphylococcus aureus was examined. Furthermore, the film was used for meat packaging at a temperature of 4°C for a duration of 26 days. Data analysis revealed an improvement in the mechanical properties and water absorption of the film following the addition of nano-cellulose and nisin. The presence of nisin in the CH-CN film was confirmed through analysis of FTIR, XRD, and SEM data. Antimicrobial analysis of film determined the high potential of nisin as an antimicrobial agent in CH-CN-N film. Compared to the control, the CH-CN-N film successfully inhibited the growth of spoilage bacteria in meat for 26 days. Additionally, the sensory properties of meat packaged with this film were minimally affected. These results indicate that the chitosan-nano-cellulose-nisin film is suitable for utilization in food systems and medical applications. [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]

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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]

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]

Abstract The effects of random dislocations on the vibrational properties of finite-length RNA and DNA macro-structures have been investigated by means of a harmonic Hamiltonian and the Green’s function method. The RNA molecule has been modeled using a half ladder model, and three models (a fishbone model and two different strand models) have been employed to model the structure of DNA. The lengths of the finite and cyclic systems are gradually increased to more accurately approximate the structures of RNA and DNA. Springs whose behaviors are governed by Hooke’s constitutive law have been used to represent the bonds between the masses, with the stiffness of the vertical springs randomly changing along the length of each model. This results in a more realistic representation of the inherent randomness of the studied structures. To investigate the effect of random dislocations on the mechanical response of the studied systems, it has been assumed that a random mass-spring ensemble has been knocked out of place by an external force. It has been found that increasing the number of building blocks along the length of the models suppresses the influence of dislocations on the vibration spectra of RNA and DNA. It was also observed that at low frequencies, the influence of dislocations becomes more pronounced. Besides, taking into account the collective mass of the sugar-phosphate backbone results in the appearance of gaps in the vibration spectra. By introducing dislocations into the models, additional dislocation-induced vibrational states appear in the DOS curves. What stands out from the results is that the responses of the studied systems to these changes are strictly nonlinear. The employed methodology can be applied to investigate the mechanical response of damaged RNA and DNA.

Poly(vinyl alcohol) (PVA) based hydrogels have gained more interest in the field of biomaterials because of their many biomedical uses (i.e., wound healing, drug delivery, and tissue engineering) and intrinsic physicochemical and biological characteristics. They can be made using a variety of synthetic techniques, but all of them are very time-consuming. Among them, photopolymerization also referred to as light-induced polymerization, has drawn a lot of attention because of its benefits, which include not requiring the use of solvents, easy and quick network formation, energy efficiency, quick processing, control over both space and time and reliability of crosslinking density and matrix strength. Ultraviolet (UV)-curable hydrogels containing PVA as a main component are gaining interest because of their excellent properties, including biodegradability, biocompatibility, less cytotoxicity and remarkable mechanical strength. This review highlights the significance of UV curable systems and their components, types, advantages and disadvantages of photoinitiators (PIs), UV curable monomers and their structures, properties of UV-cured PVA hybrid hydrogels, and their characterizations and applications in different fields. The photopolymerization mechanisms, tunable properties, and unique advantages of these hydrogels have been explored in detail. Furthermore, it sheds light on recent advancements in PVA-based hydrogels research and future exploration in this domain.

Abstract 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.

The drastic increase in the amount of packaging waste from conventional plastics, caused by improper waste management, is a serious challenge for the planet. It is therefore worth considering how we can solve this problem. Thus, it is necessary to develop new polymeric materials that retain the functional properties of traditional plastics but are susceptible to degradation with the participation of microorganisms. The development of new eco-friendly materials requires a holistic approach in terms of their disposal. Organic recycling enables the disposal of biodegradable packaging along with food remains that are difficult to remove. The article presents a study on the degradation of biocomposites of polylactide with cork in various environments (water, buffer, and compost). The obtained results indicate a clear influence of the presence of the filler and its amount on the degradation profile of the composites. In addition, the effect of sample shrinkage was observed, especially during degradation in water, where the pH decreases during the process due to the appearance of degradation products. This effect may be important not only for the degradation profile of the packaging but also during its use. Packaging distorted due to shrinkage may be a sign of improper product storage.

The protein from black soldier fly larvae was used as a functional ingredient of a novel green nanofiber. Larvae protein powder (LP) was blended with biodegradable poly(ε-caprolactone) (PCL) and processed in an electrospinning machine using a coaxial feeding/mixing method to produce nanofibers approximately 100–350 nm in diameter. To improve the dispersion and interface bonding of various PCL/LP nanofiber components, a homemade compatibilizer, maleic anhydridegrafted poly(ε-caprolactone) (MPCL), was added to form MPCL/LP nanofibers. The structure, morphology, mechanical properties, water absorption, cytocompatibility, wound healing, and biodegradability of PCL/LP and MPCL/LP nanofiber mats were investigated. The results showed enhanced adhesion in the MPCL/LP nanofiber mats compared to PCL/LP nanofiber mats; additionally, the MPCL/LP nanofibers exhibited increases of approximately 0.7–2.2 MPa in breaking strength and 9.0–22.8 MPa in Young’s modulus. Decomposition tests using a simulated body fluid revealed that the addition of LP enhanced the decomposition rate of both PCL/LP and MPCL/LP nanofiber mats and in vitro protein release. Cell proliferation and migration analysis indicated that PCL, MPCL, and their composites were biocompatible for fibroblast (FB) growth. Biodegradability was tested in a 30 day soil test. When the LP content was 20 wt%, the degradation rate exceeded 50%.

Abstract 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.

Global regulations are guiding society towards more sustainable material solutions. This increasing awareness of the need for environmentally friendly alternatives has led to a greater emphasis on biocomposites, which combine natural fibers with bio-based polymers. This study investigates how bleached softwood pulp fibers (BSWPF) and unbleached softwood pulp fibers (UBSWPF) affect the characteristics of poly(lactic acid) (PLA)-based biocomposites. UBSWPF is a more cost-effective option because it is manufactured with less processing steps than BSWPF. However, it is largely unexplored as a reinforcement in biopolymers. Through investigating the mechanical, thermal, and morphological aspects of the biocomposites, this study showed that UBSWP increased the modulus and impact strength of the PLA biocomposites better than BSWPF. The impact strength, modulus, and tensile strength of PLA-BSWPF and PLA-UBSWPF improved as the fiber content increased. However, a decrease in tensile strength was seen at higher percentages of UBSWPF in PLA. Despite the decrease in tensile strength at higher UBSWPF concentrations, both types of fibers improved the mechanical properties of the biocomposites, demonstrating a potential sustainable reinforcing material for PLA biocomposites.

Abstract 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. Graphical Abstract

In this study, the effects of two environmentally-friendly pulping methods along with two different reactive compatibilization methods on the foamability of poly (lactic acid) (PLA)/rice straw (RS) biocomposites have been investigated. RS as an annually renewable agricultural waste is low-cost and available. Melt-compounding and melt-foaming processes were performed through a twin-screw extrusion processing. The correlations between processing and microstructure were studied. The findings show that the RS pulping with sodium bicarbonate (SB) solution leads to the lignocellulosic particles with a porous structure. The structure causes the filler/matrix mechanical engagement and improves the interfacial adhesion and rheological properties, hence forming smaller cells with the narrowest cell size distribution. In contrast, applying ultrasound waves on the RS pulp brings the particles to very smooth surfaces. These surfaces have the highest activity at the cell nucleation stage and considerably increase the foam's cell density. The reactive compatibilizers based on epoxy and maleic anhydride groups show opposing effects on the biocomposite microstructure, depending on the RS pulp type. The use of the reactive compatibilizers in the PLA/RS pulp treated with SB led to lighter foams with larger cells and higher cell densities and void fractions. Whereas the incorporation of the compatibilizers into the biocomposites containing RS pulp treated with SB and ultrasonic waves resulted in noticeably lower cell density and larger foam density. The extruded biocomposite foams with closed-cell microstructure can be used in insulation and packaging applications. [ABSTRACT FROM AUTHOR]

This study investigates the incorporation of algae-based activated carbon into polyurethane foam to improve a biocomposite for gasoil sorption. The biocomposites were thoroughly analyzed using various techniques to examine the properties of both the blank foam and the algae activated carbon foam with a carbon content of 4.41 mass% and particle diameter of 500 µm. These techniques included Scanning Electron Microscopy (SEM), thermogravimetric analysis (TGA), and density analysis. The TGA analysis revealed that the biocomposites had an impact on the onset temperature (Tonset) of the foams. Higher concentrations of the biocomposites resulted in a decrease in Tonset from approximately 310 °C in the blank foam (PUF0) to 300 °C in the composite (PUF3B). The final residue percentage also decreased from around 20% in PUF0 to 10% in PUF3B. Density analysis showed that the apparent density of the foam increased from 0.016 g/cm3 in the blank foam to 0.020 g/cm3 in the biocomposite (PUF3B), while the real density slightly decreased from 0.092 g/cm3 to 0.076 g/cm3, indicating a reduction in overall porosity from 82.5% to 74.4%. All foams that were modified showed an increase in their ability to absorb gasoil in a PUF/gasoil/water system. The optimized biocomposite (PUF1B), with 1.14 mass% of 500 µm algae carbon, displayed the highest sorption capacity, starting at approximately 50 g/g at 1.5 h and increasing to 53 g/g over 72 h. The analysis of adsorption kinetics revealed that by utilizing adsorption isotherms, particularly the Langmuir isotherm, a more accurate fit to the data was achieved. This allowed for the prediction of the maximum gasoil adsorption capacity. This study aims to further develop, analyze, and utilize biocomposites made from algae-based activated carbon and polyurethane. These materials offer a sustainable and environmentally friendly approach to cleaning up oil spills. [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]

In recent years, there has been considerable focus on ensuring that energy is used in the most efficient manner possible. This is due to the fact that globally, over 70% of energy is generated from fossil fuels. Consequently, the matter of designing and utilizing materials that will negate energy losses within the construction industry is of paramount importance. Simultaneously, the necessity for a sustainable approach to the design and production of materials is strongly emphasized. This paper presents an innovative approach to the use of a combination of mineral and plant-based fillers in polyurethane foam technology as a thermal insulation material with the potential to be used in construction to reduce energy consumption. Polyurethane composites containing fly ash from biomass combustion and the addition of rice, sunflower, and buckwheat husks as plant fillers were proposed. The structure of the obtained materials was studied, and the most important physical properties were analyzed. These included apparent density, dimensional stability, water absorption, and the effects of UV radiation and water influence on the carbon, hydrogen, nitrogen, and oxygen content. Moreover, the mechanical properties of the materials were investigated, including compressive strength and brittleness. Additionally, the foams were subjected to flammability tests using a cone calorimeter. Furthermore, additional parameters were determined, including the limiting oxygen index and the vertical and horizontal flammability tests. The results demonstrate the beneficial effects of combining mineral and vegetable fillers in polyurethane foam. [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]

The drastic increase in the amount of packaging waste from conventional plastics, caused by improper waste management, is a serious challenge for the planet. It is therefore worth considering how we can solve this problem. Thus, it is necessary to develop new polymeric materials that retain the functional properties of traditional plastics but are susceptible to degradation with the participation of microorganisms. The development of new eco-friendly materials requires a holistic approach in terms of their disposal. Organic recycling enables the disposal of biodegradable packaging along with food remains that are difficult to remove. The article presents a study on the degradation of biocomposites of polylactide with cork in various environments (water, buffer, and compost). The obtained results indicate a clear influence of the presence of the filler and its amount on the degradation profile of the composites. In addition, the effect of sample shrinkage was observed, especially during degradation in water, where the pH decreases during the process due to the appearance of degradation products. This effect may be important not only for the degradation profile of the packaging but also during its use. Packaging distorted due to shrinkage may be a sign of improper product storage. [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]

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]

Artificial reefs represent useful tools to revitalize coastal and ocean ecosystems. Their formulation determines the biofilm formation which is the prerequisite for the colonization process by marine micro- and macroorganisms. In comparison with concrete, biobased polymers offer improved characteristics, including architecture, formulation, rugosity and recycling. This article aims to explore a new scale of artificial reef made of biocomposites reinforced with a high flax fibre (Linum utilatissimum) content (30%). Cellular adhesion and resulting biofilm formation were assessed using two marine microorganisms: Pseudoalteromonas sp. 3J6 and Cylindrotheca closterium. The influence of flax fibre leachates and plastic monomers on the growth of those marine microorganisms were also evaluated. Results indicated that the introduction of flax fibres inside the polymer matrix modified its physicochemical properties thus modulating adhesion and biofilm formation depending on the microorganism. This study gives insights for further developments of novel functionalized artificial reefs made of biocomposites. [ABSTRACT FROM AUTHOR]

This study investigates the complex relationships between process parameters and material properties in FDM-based 3D-printed biocomposites using explainable AI techniques. We examine the effects of key parameters, including biochar content (BC), layer thickness (LT), raster angle (RA), infill pattern (IP), and infill density (ID), on the tensile, flexural, and impact strengths of FDM-printed pure PLA and biochar-reinforced PLA composites. Mechanical testing was used to measure the ultimate tensile strength (UTS), flexural strength (FS), and impact strength (IS) of the 3D-printed samples. The extreme gradient boosting (XGB) algorithm was used to build a predictive model based on the data collected from mechanical testing. Shapley Additive Explanations (SHAP), Local Interpretable Model-Agnostic Explanations (LIME), and Partial Dependence Plot (PDP) techniques were implemented to understand the effects of the interactions of key parameters on mechanical properties such as UTS, FS, and IS. Prediction by XGB was accurate for UTS, FS, and IS, with R-squared values of 0.96, 0.95, and 0.85, respectively. The explanation showed that infill density has the most significant influence on UTS and FS, with SHAP values of +2.75 and +5.8, respectively. BC has the most significant influence on IS, with a SHAP value of +2.69. PDP reveals that using 0.3 mm LT and 30° RA enhances mechanical properties. This study contributes to the field of the application of artificial intelligence in additive manufacturing. A novel approach is presented in which machine learning and XAI techniques such as SHAP, LIME, and PDP are combined and used not only for optimization but also to provide valuable insights about the interaction of the process parameters with mechanical properties. [ABSTRACT FROM AUTHOR]

An innovative microcrystalline cellulose (MCC) natural fibre powder-reinforced PLA biocomposite was investigated using the hand lay-up technique. The polymer matrix composite (PMC) samples were prepared by varying the weight percentages (wt.%) of both PLA matrix and MCC reinforcement: pure PLA/100:0, 90:10, 80:20, 70:30, 60:40 and 50:50 wt.%, respectively. From the results obtained, MCC powder, with its impressive aspect ratio, proved to be an ideal reinforcement for the PLA, exhibiting exceptional mechanical properties. It was evident that the 80:20 wt.% biocomposite sample exhibited the maximum improvement in the tensile, flexural, notched impact, compressive strength and hardness by 28.85%, 20.00%, 91.66%, 21.53% and 35.82%, respectively compared to the pure PLA sample. Similarly, during the thermogravimetric analysis (TGA), the same 80:20 wt.% biocomposite sample showed a minimum weight loss of 20% at 400°C, among others. The morphological study using Field Emission Scanning Electron Microscopy (FE-SEM) revealed that the uniform distribution of cellulose reinforcement in the PLA matrix actively improved the mechanical properties of the biocomposites, especially the optimal 80:20 wt.% sample. Importantly, it was evident that the optimal PLA/cellulose biocomposite sample could be a suitable and alternative sustainable, environmentally friendly and biodegradable material for semi/structural applications, replacing synthetic and traditional components. [ABSTRACT FROM AUTHOR]