Natural Biocomposites Research Articles

The Use of Recycled Cement-Bonded Particle Board Waste in the Development of Lightweight Biocomposites.

Cement-bonded particle boards are gaining popularity globally due to their durability, strength, and, more importantly, environmental sustainability. The increasing demand for these materials has also created the necessity for the sustainable recycling of these materials. In this study, the potential to recycle wood-wool cement board (WWCB) waste into new lightweight insulation biocomposite material was examined. The waste WWCBs were crushed and separated into a fine aggregate fraction, and WWCB production line residues were also collected and compared. The crushed WWCBs were used to produce biocomposites with various compaction ratios and different binder-to-aggregate ratios. To improve their thermal properties and reduce their density, hemp shives were used to partially replace the recycled WWCB aggregate. Their physical, mechanical (compressive and flexural strength), and thermal properties were evaluated, and the drying process of the biocomposites was characterized. The results showed that the density of the produced biocomposites ranged from 390 to 510 kg/m3. The reduction in density was limited due to the presence of cement particles in the aggregate. The incorporation of hemp shives allowed us to reduce the density below 200 kg/m3. The thermal conductivity of the biocomposites ranged from 0.054 to 0.084 W/(mK), placing the material within the effective range of natural biocomposites. This research has demonstrated that industrially produced WWCBs can be successfully recycled to produce sustainable lightweight cement-bonded insulation materials.

Multifunctional Biocomposite Materials from Chlorella vulgaris Microalgae.

Extrusion 3D-printing of biopolymers and natural fiber-based biocomposites enables the fabrication of complex structures, ranging from implants' scaffolds to eco-friendly structural materials. However, conventional polymer extrusion requires high energy consumption to reduce viscosity, and natural fiber reinforcement often requires harsh chemical treatments to improve adhesion. We address these challenges by introducing a sustainable framework to fabricate natural biocomposites using Chlorella vulgaris microalgae as the matrix. Through bioink optimization and process refinement, we produced lightweight, multifunctional materials with hierarchical architectures. Infrared spectroscopy analysis reveals that hydrogen bonding plays a critical role in the binding and reinforcement of Chlorella cells by hydroxyethyl cellulose (HEC). As water content decreases, the hydrogen bonding network evolves from water-mediated interactions to direct hydrogen bonds between HEC and Chlorella, enhancing the mechanical properties. A controlled dehydration process maintains continuous microalgae morphology, preventing cracking. The resulting biocomposites exhibit a bending stiffness of 1.6 GPa and isotropic heat transfer and thermal conductivity of 0.10 W/mK at room temperature, demonstrating effective thermal insulation. These characteristics make Chlorella biocomposites promising candidates for applications requiring both structural performance and thermal insulation, offering a sustainable alternative to conventional materials in response to growing environmental demands.

A REVIEW OF MYCELIUM-BASED BIO-COMPOSITES AND THEIR POSSIBLE APPLICATION IN ARCHITECTURE

Construction industry is one of the largest consumers of natural resources, and so faces enormous difficulties in reducing the environmental impact of existing consumption habits. Growing industry demand for biodegradable or alternative materials and products derived from renewable resources, has recently prompted researchers from diverse fields to work in this area. They are working to find sustainable alternatives and develop natural bio-composites to replace various petroleum-based products in the interest of the environment. One such bio-composite derived from mycelium can provide a renewable and biodegradable alternative to conventional building materials. Mycelium, the fibrous root system of fungi, grows on organic substrates under controlled environmental conditions to produce these biomaterials. This article provides a comprehensive analysis of the current research and applications of mycelium-based materials in the field of architecture.

Advances in understanding insect chitin biosynthesis

Chitin, a natural polymer of N-acetylglucosamine chains, is a principal component of the apical extracellular matrix in arthropods. Chitin microfibrils serve as structural components of natural biocomposites present in the extracellular matrix of a variety of invertebrates including sponges, molluscs, nematodes, fungi and arthropods. In this review, we summarize the frontier advances of insect chitin synthesis. More specifically, we focus on the chitin synthase (CHS), which catalyzes the key biosynthesis step. CHS is also known as an attractive insecticidal target in that this enzyme is absent in mammals, birds or plants. As no insect chitin synthase structure have been reported so far, we review recent studies on glycosyltransferase domain structures derived from fungi and oomycetes, which are conserved in CHS from all species containing chitin. Auxiliary proteins, which coordinate with CHS in chitin biosynthesis and assembly, are also discussed.

Interlaminar fracture energy and its dependence on microstructure in three bamboo species of commercial importance

Bamboo, one of the versatile and natural bio-composite, is being extensively used in structural and non-structural application. Studying the interlaminar fracture behaviour of bamboos is very important for its usage in load bearing situation as well as processing to fabricate the composite products. The studies reported here presents the experimental work on Mode I fracture of three structural grade sympodial bamboo species, viz., Dendrocalamus brandisii, Bambusa bambos and Guadua angustifolia. The interlaminar fracture energy was evaluated in the inner, middle and outer layers of each bamboo by the double cantilever beam (DCB) test method using compliance calibration-based beam theory (CCBT). The volume fraction of the fibres in each layer of three bamboos was computed by observing the microstructure in the cross-section and measuring the fibre bearing area after maceration. Dependence of the fracture energy on volume fraction of fibre in each layer of three bamboo species was discussed. The fractured bamboo surfaces were observed under high resolution scanning electron microscope and possible fracture mechanisms were investigated. The layer-wise crystallinity parameters were computed using X-ray diffraction spectra. The middle layer of bamboo exhibited higher fracture energy followed by outer and inner layers. However, the volume fraction of fibres was found to reduce from outer to inner layers. It was found that higher crystallinity leads to lower fracture energy in these bamboos. The data on interlaminar fracture energy of three bamboos is found to be important for utilizing in various load bearing applications.

Robust and Scalable In Vitro Surface Mineralization of Inert Polymers with a Rationally Designed Molecular Bridge.

The artificial integration of inorganic materials onto polymers to create the analogues of natural biocomposites is an attractive field in materials science. However, due to significant diversity in the interfacial properties of two kinds of materials, advanced synthesis methods are quite complicated and the resultant materials are always vulnerable to external environments, which limits their application scenarios and makes them unsuitable for scalable production. Herein, we report a simple and universal approach to achieve robust and scalable surface mineralization of polymers using a rationally designed triple functional molecular bridge of fluorosilane, 3-[(perfluorohexyl sulfonyl) amino] propyltriethoxy silane (PFSS). In a two-step solution deposition, the fluoroalkyl and siloxane of the PFSS take charge of its adhesion and immobilization onto polymers by hydrophobic interaction and wrapping-like chemical cross-linking, and then the assembly and growth of inorganic nanoclusters for integration are achieved by strong chemical coordination of PFSS sulfonamide. The versatile mineralization of inorganic oxides (e.g., TiO2, SiO2, and Fe2O3) onto chemically inert polymer surfaces was realized very well. The resultant mineralized materials exhibit robust and multiple functionalities for hostile applications, such as hydrophilic membranes for removing oils in strong acidic and alkaline wastewaters, fabrics with advanced anti-bacteria for healthy wearing, and plates with strong mechanical performance for better use. Experimental results and theoretical calculations confirmed the homogenous distribution of the PFSS onto polymers via cross-linking for robust coordination with inorganic oxides. These results demonstrate a skillful enlightenment in the design of high-performance mineralized polymer materials used as membranes, fabrics, and medical devices.

Green technology of natural fiber reinforced bio-composites as alternative sustainable product

Proactive strategies are being opted by metallurgical, foundry and manufacturing industries with respect to their experiences working with product designing based on product life cycle assessments. Without the consideration of the potential impacts on the life cycle, the development of new products would barely be sustainable. “Green” composites or bio-composites are fully degradable composites mainly consisting of a blend of biopolymer matrix and natural fibers which act as a reinforcing phase. In this study, natural bio-composite was reviewed as an alternative sustainable product. The types of natural fibers were also described as raw material of natural bio-composite. In addition, development natural fibers nowadays were mentioned. Furthermore, the application of natural fiber reinforced bio-composites was also presented.

Utilisation of Paunch Waste as a Natural Fibre in Biocomposites.

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

Differential analyses of ginger extract implant coating material

Background: Different types of material were used as implants; the most common is titanium and its alloy, and recently zirconia acquired robust interest due to many desirable properties, Natural biocomposites recently received widespread attention as an active coating covering metallic implants due to their bioactivity, availability, and affordability. Aim: This study aims to present the evolvement and characterization of ginger extract materials overlying Yttria-stabilized tetragonal zirconia and PEEK substrate. Material and method: The methodology of the present study involved preparation of ginger extract powder twenty disc-shaped specimens with a dimension of 10 mm, from partially sintered Yttria-stabilized tetragonal zirconia polycrystal and PEEK . The naturally prepared ginger extract powder was deposited via cold spraying device. The prepared ginger extract characterized by particle size analyzer and ginger extract while The experimental specimens were characterized by, field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectroscopy (EDX). Conclusion :naturally prepared ginger extract exhibit uniform distribution and good adherence to the samples Therefore, it can be used as a coating material for zirconia and PEEK implants with promising biological and mechanical properties.

Hierarchical structure design of Strombus gigas shell inspired laminated artificial composites and the mechanical performance optimization strategy

Strombus gigas shell is a natural biocomposite with good strength and extraordinary toughness, inspired by its internal refined hierarchical microstructures, a soft and hard phases composed cross-laminated hierarchical artificial structural composite that reinforced by discontinuous fiber was designed and prepared by 3D printing, and an investigation on the failure behavior and its strengthening and toughing mechanisms was carried out. It shows that the geometric configuration of the crossed-structure will regulate the local stress status in the hard phase and soft interface of the hierarchical structure significantly, and four different failure modes of this structure were proposed. Through the optimal design of the crossed-structure, the internal structure will undergo adaptive adjustment during loading process, then multiple failure forms and energy dissipation modes may burst out together and realize the improved combination of strength and toughness. This result may provide an optimization strategy for the lightweight composites design and additive manufacturing process.

Physio-mechanical properties and applications of natural fiber reinforced bio-composites

At present, natural or lignocellulosic fiber-based bio composites are the talk of the town due to their low density, cost effective, eco-friendly, renewable properties. Bio fibers such as jute, kenaf, pineapple, sugarcane, flax, leaf, hemp, wool, silk etc obtained from plants or nature which can be utilized to obtain new high performance polymer composite materials. The physical and mechanical characteristics of these bio fibers (e.g., tensile properties, flexural stress-strain behaviour, fracture strength, impact strength) make them more sustainable and attractive than synthetic fibers with a remarkable biodegradable characteristic. The aim of this review is to give a thorough overview on natural fibers and natural fiber reinforced bio composite materials, their major physical and mechanical properties and potential applications.

Unveiling characteristic proteins for the structural development of beetle elytra

Beetles possess a set of highly modified and tanned forewings, elytra, which are lightweight yet rigid and tough. Immediately after eclosion, the elytra are initially thin, pale and soft. However, they rapidly expand and subsequently become hardened and often dark, resulting from both pigmentation and sclerotization. Here, we identified changes in protein composition during the developmental processes of the elytra in the Japanese rhinoceros beetle, Trypoxylus dichotomus. Using mass spectrometry, a total of 414 proteins were identified from both untanned and tanned elytra, including 31 cuticular proteins (CPs), which constitute one of the major components of insect cuticles. Moreover, CPs containing Rebers and Riddiford motifs (CPR), the most abundant CP family, were separated into two groups based on their expression and amino acid sequences, such as a Gly-rich sequence region and Ala-Ala-Pro repeats. These protein groups may play crucial roles in elytra formation at different time points, likely including self-assembly of chitin nanofibers that control elytral macro and microstructures and dictate changes in other properties (i.e., mechanical property). Clarification of the protein functions will enhance the understanding of elytra formation and potentially benefit the development of lightweight materials for industrial and biomedical applications. Statement of significanceThe beetle elytron is a light-weight natural bio-composite which displays high stiffness and toughness. This structure is composed of chitin fibrils and proteins, some of which are responsible for architectural development and hardening. This work, which involves insights from molecular biology and materials science, investigated changes in proteomic, architectural, and localized mechanical characteristics of elytra from the Japanese rhinoceros beetle to understand molecular mechanisms driving elytra development. In the present study, we identified a set of new protein groups which are likely related to the structural development of elytra and has potential for new pathways for processing green materials.

Mechanical and thermophysical model of date palm fiber and beet pulp composite as natural thermal insulant

AbstractFor the transport of frozen products, it is necessary to preserve their quality and enhance their longevity. It aimed to assess the insulation performance of the composite containing date palm fiber and beet pulp in maintaining low temperature during the transport of frozen products. Therefore, this study investigated the physical, thermal, and mechanical properties of date palm fiber and beet pulp composites for different mass fractions of 0, 2.5, 7.5, and 10%, both as stand‐alone and as compounds added to hemihydrate gypsum by using the response surface method to state an optimized system. Results showed that by increasing the fractions of date palm fiber and beet pulp, the density of composite samples reduced from 880.02 kg/m3 to 785 kg/m3; however, water absorption increased significantly (by 101.39%). The highest flexural and compressive strengths of the control were, respectively, 4.6 and 26.67 MPa, whereas the lowest of said strengths were, respectively, 3.5 and 42.91 MPa in samples containing 10% palm fiber and 10% beet pulp. Additionally, for the same fiber ratios, the thermal conductivity of composite samples was reduced by 67% compared to the control sample. After optimization, the best mass ratios for palm fiber and sugar beet bagasse were, respectively, 3.05% and 10%. For these samples, water absorption was 96.69%; flexural and compressive strengths were, respectively, 6.27 and 3.87 MPa; thermal conductivity was 0.51 W/mK; and density was 844.15 kg/m3. These properties show that a composite insulant containing date palm fiber and beet pulp are a good candidate for developing thermal insulants.Practical applicationsReducing microbic growth and delaying fat and protein oxidation during the storage can increase the durability of food and agriculture products, particularly different types of meats and dairies. To this end, a safe cold cycle is necessary for proper preservation during transport and storage. Cold transport is the main part of the cold chain required for preserving the quality of freshly frozen degradable products. Therefore, in addition to cold storages and refrigerated transport vehicles, the packages are also important. The goal of this research is the progressing of a natural biocomposite that is used as thermal insulant.

Lignocellulosic Corn Stover Biomass Pre-Treatment by Deep Eutectic Solvents (DES) for Biomethane Production Process by Bioresource Anaerobic Digestion

The valorization study of the largely available corn stover waste biomass after pretreatment with deep eutectic solvent (DES) for biomethane production in one-liter glass bioreactors by anaerobic digestion for 21 days was presented. Ammonium thiocyanate and urea deep eutectic solvent pretreatments under different conditions in terms of the components ratio and temperature were examined on corn stover waste biomass. The lignocellulose biomass was characterized in detail for its chemistry and morphology to determine the effect of the pretreatment on the natural biocomposite. Furthermore, the implications on biomethane production through anaerobic digestion with different loadings of corn stover biomass at 35 g/L and 50 g/L were tested. The results showed an increase of 48% for a cumulative biomethane production for a DES-pretreated biomass, using a solid-to-liquid ratio of 1:2 at 100 °C for 60 min, which is a strong indication that DES-pretreatment significantly enhanced biomethane production.

Effective recovery of ytterbium through biosorption using crosslinked sericin-alginate beads: A complete continuous packed-bed column study

The recovery of rare-earth from secondary sources is essential for cleaner production. The development of natural biocomposites is promising for this purpose. Sericin is a waste protein from silk manufacturing. The highly polar groups on the surface of sericin facilitate blending and crosslinking with other polymers to produce biocomposites with improved properties. In this work, we investigate ytterbium recovery onto a natural biocomposite based on sericin/alginate/poly(vinyl alcohol) (SAPVA) in packed-bed column, aiming to establish a profitable application for sericin. Effects of flow rate and ytterbium inlet concentration showed that the highest exhaustion biosorption capacity (128.39 mg/g) and lowest mass transfer zone (4.13 cm) were reached under the operating conditions of 0.03 L/h and 87.95 mg/L. Four reusability cycles were performed under the optimum operating conditions using 0.3 mol/L HNO3. Ytterbium recovery was highly successful; desorption efficiency was higher than 97% and a final ytterbium-rich concentrate (3870 mg/L) was 44 times higher than input concentration. Regenerated beads characterization showed that the cation exchange mechanism plays a major function in continuous biosorption of ytterbium. SAPVA beads also showed higher biosorption/desorption performance for ytterbium than other competing ions. These results suggest the application of SAPVA may be an alternative for large-scale ytterbium recovery.

Structure and moisture effect on the mechanical behavior of a natural biocomposite, buffalo horn sheath

Buffalo horn sheath is one of the typically natural composites with balanced strength and toughness. It demonstrates a structural hierarchy with stacked and corrugate-shaped lamellae, longitudinally sutured scaly cells and unidirectional keratin fibers. This work clarifies the influences of protein secondary structure, anisotropy microstructure, and moisture on flexural properties of sheath. From distal to proximal sections of sheath, flexural strength and modulus decrease, which may relate to the varied secondary structure. The mechanical properties are demonstrated to be enhanced along longitudinal direction correlated to the anisotropic microstructure. Besides, the strength and modulus can be weakened by the plasticization of moisture induced by rehydration. The fracture modes, which include matrix failure, interface dissociation and fiber breakage, are further correlated with the effects of anisotropy and moisture to illustrate damage patterns of horn sheath under different conditions. This study may provide reference to the structure-property relationship of natural composites and design strategy of bioinspired composites with tubular shape and anisotropy.

Teorijsko istraživanje ljušturi mekušaca - istraživanje energetskih pejzaža polimorfa CaCo3 i supstitucija elemenata - kratak pregledni rad

Due to the remarkable properties achieved under ambient conditions and with quite limited components, mollusk shells are very appealing natural bio-composites used as inspiration for new advanced materials. Calcium carbonate which is among the most widespread biominerals is used by mollusks as a building material that constitutes 95-99% of their shells. Within the investigation of calcium carbonate polymorphs present in the shells, diverse theoretical and experimental studies were performed, however, further research of these crystalline forms is required. There are very little researches on the energy landscapes of biogenic calcium carbonate which can provide us information about the free energies of already known as well as newly discovered plausible structures. To investigate the structural, mechanical, elastic, or vibrational properties and to predict new possible structures of biogenic calcium carbonate, different calculation methods could be employed. Some of these studies are presented and discussed in this paper.

Heat analysis of single point cutting tool coated with different natural bio composite

The paper presents the selection of suitable coating material for a single-point cutting tool. The coated tool exhibited superior wear and heat resistance. The coating is done over an uncoated tool. Single point cutting tool coating is done according to the points and regions we found getting affected due to cutting tool operation and due to thermal effects on it due to heat. The analysis of a coated tool is compared using three different coatings. The normal cutting tool is selected and subjected to various load and thermal conditions. The properties to determine the stress, deflection, heat flux and temperature sustained is the determination of single point cutting tool of various materials.

Effect of the Polyethyleneimine Coating on the Bending Properties of the Natural Fiber-Reinforced Biocomposites

Effect of the Polyethyleneimine Coating on the Bending Properties of the Natural Fiber-Reinforced Biocomposites

Chitosan in Surface Modification for Bone Tissue Engineering Applications.

Traditional methods of bone defect repair include autografts, allografts, surgical reconstruction, and metal implants that have several disadvantages such as donor site morbidity, rejection, risk of disease transmission, and repetitive surgery. Biomaterial-based bone reconstructions can, therefore, be an efficient alternative due to the inherent properties of the materials. Chitosan (CS), the deacetylated form of chitin, is a biopolymer having a wide array of applicability in regenerative tissue applications owing to its biocompatible, in vitro degradative and bioresorbable nature. Extensive studies are being carried out using CS to augment the properties of the already existing methods and to also improve the applicability of CS-based biocomposites in bone tissue repair. In this review, the suitability of CS as a surface modifier has been discussed in detail for the already existing implants, surface modifications of CS-based natural biocomposites for bone tissue regeneration, and the wide range of techniques that can introduce these modifications. CS, being a natural polymer, possesses advantageous properties including surface modifier that makes it a suitable candidate for bone regeneration, and further research to investigate its osteogenic potential in vivo along with the molecular and signaling mechanisms involved in bone regeneration can aid in expanding its applicability in clinical trials.