Advances in industrial prospective of cellulosic macromolecules enriched banana biofibre resources: A review

Pioneering a paradigm shift in tissue engineering and regeneration with polysaccharides and proteins-based scaffolds: A comprehensive review

In the realm of modern medicine, tissue engineering and regeneration stands as a beacon of hope, offering the promise of restoring form and function to damaged or diseased organs and tissues. Central to this revolutionary field are biological macromolecules-nature's own blueprints for regeneration. The growing interest in bio-derived macromolecules and their composites is driven by their environmentally friendly qualities, renewable nature, minimal carbon footprint, and widespread availability in our ecosystem. Capitalizing on these unique attributes, specific composites can be tailored and enhanced for potential utilization in the realm of tissue engineering (TE). This review predominantly concentrates on the present research trends involving TE scaffolds constructed from polysaccharides, proteins and glycosaminoglycans. It provides an overview of the prerequisites, production methods, and TE applications associated with a range of biological macromolecules. Furthermore, it tackles the challenges and opportunities arising from the adoption of these biomaterials in the field of TE. This review also presents a novel perspective on the development of functional biomaterials with broad applicability across various biomedical applications.

Plant-biomass-based hybrid seed wraps mitigate yield and post-harvest losses among smallholder farmers in sub-Saharan Africa

Sustainable practices that reduce food loss are essential for enhancing global food security. We report a 'wrap and plant' seed treatment platform to protect crops from soil-borne pathogens. Developed from the abundantly available wastes of banana harvest and recycled old, corrugated cardboard boxes via chemical-free pulping, these paper-like biodegradable seed wraps exhibit tunable integrity and bioavailability of loaded moieties. These wraps were used for nematode control on yam (Dioscorea cayenensis-rotundata) seed pieces in Benin, a major producer of this staple crop in the sub-Saharan African 'yam belt'. Our seed wraps loaded with ultra-low-volume abamectin (1/100 ≤ commercial formulation) consistently controlled yam nematode (Scutellonema bradys) populations while considerably increasing the yield at various locations over 2015-2018. Substantial reduction in post-harvest tuber weight loss and cracking was observed after 3 and 5 months of storage, contributing to increased value, nutrition and stakeholders' preference for the wrap and plant treatment.

Agriculture Waste Biomass Repurposed into Natural Fibers: A Circular Bioeconomy Perspective

Fibers come from natural and fossil resources and are an essential commodity widely used by textile industries. Considering current supply and future demands, the repurposing of agricultural residues into fibers is an eco-friendly, attractive option that might mitigate environmental pollution. In this review, we have summarized multiple alternate secondary sources for fiber production, with a case study using banana plant residual biomass, a common agricultural waste in many developing countries. Specifically, in this review we have compared the different processing methods, e.g., chemical, mechanical, or biological methods, for repurposing agricultural residual biomass (including banana waste) into fibers. The development and analysis of an integrated biorefinery approach is needed to promote the fiber production from various agro-residual biomasses within the framework of circular bioeconomic concepts.

Comparative Analysis the Complete Chloroplast Genomes of Nine Musa Species: Genomic Features, Comparative Analysis, and Phylogenetic Implications

Musa (family Musaceae) is monocotyledonous plants in order Zingiberales, which grows in tropical and subtropical regions. It is one of the most important tropical fruit trees in the world. Herein, we used next-generation sequencing technology to assemble and perform in-depth analysis of the chloroplast genome of nine new Musa plants for the first time, including genome structure, GC content, repeat structure, codon usage, nucleotide diversity and etc. The entire length of the Musa chloroplast genome ranged from 167,975 to 172,653 bp, including 113 distinct genes comprising 79 protein-coding genes, 30 transfer RNA (tRNA) genes and four ribosomal RNA (rRNA) genes. In comparative analysis, we found that the contraction and expansion of the inverted repeat (IR) regions resulted in the doubling of the rps19 gene. The several non-coding sites (psbI-atpA, atpH-atpI, rpoB-petN, psbM-psbD, ndhf-rpl32, and ndhG-ndhI) and three genes (ycf1, ycf2, and accD) showed significant variation, indicating that they have the potential of molecular markers. Phylogenetic analysis based on the complete chloroplast genome and coding sequences of 77 protein-coding genes confirmed that Musa can be mainly divided into two groups. These genomic sequences provide molecular foundation for the development and utilization of Musa plants resources. This result may contribute to the understanding of the evolution pattern, phylogenetic relationships as well as classification of Musa plants.

Bioepoxy based hybrid composites from nano-fillers of chicken feather and lignocellulose Ceiba Pentandra

In this work, fillers of waste chicken feather and abundantly available lignocellulose Ceiba Pentandra bark fibers were used as reinforcement with Biopoxy matrix to produce the sustainable composites. The aim of this work was to evaluate the mechanical, thermal, dimensional stability, and morphological performance of waste chicken feather fiber/Ceiba Pentandra bark fiber filler as potential reinforcement in carbon fabric-layered bioepoxy hybrid composites intended for engineering applications. These composites were prepared by a simple, low cost and user-friendly fabrication methods. The mechanical (tensile, flexural, impact, hardness), dimensional stability, thermal stability, and morphological properties of composites were characterized. The Ceiba Pentandra bark fiber filler-reinforced carbon fabric-layered bioepoxy hybrid composites display better mechanical performance compared to chicken feather fiber/Ceiba Pentandra bark fiber reinforced carbon fabrics layered bioepoxy hybrid composites. The Scanning electron micrographs indicated that the composites exhibited good adhesion at the interface of the reinforcement material and matrix system. The thermogravimetric studies revealed that the composites possess multiple degradation steps, however, they are stable up to 300 °C. The thermos-mechanical studies showed good dimensional stability of the composites. Both studied composites display better thermal and mechanical performance compared to neat bioepoxy or non-bioepoxy thermosets and are suitable for semi-structural applications.

Biobased Polyurethane Composite Foams Reinforced with Plum Stones and Silanized Plum Stones

In the following study, ground plum stones and silanized ground plum stones were used as natural fillers for novel polyurethane (PUR) composite foams. The impact of 1, 2, and 5 wt.% of fillers on the cellular structure, foaming parameters, and mechanical, thermomechanical, and thermal properties of produced foams were assessed. The results showed that the silanization process leads to acquiring fillers with a smoother surface compared to unmodified filler. The results also showed that the morphology of the obtained materials is affected by the type and content of filler. Moreover, the modified PUR foams showed improved properties. For example, compared with the reference foam (PUR_REF), the foam with the addition of 1 wt.% of unmodified plum filler showed better mechanical properties, such as higher compressive strength (~8% improvement) and better flexural strength (~6% improvement). The addition of silanized plum filler improved the thermal stability and hydrophobic character of PUR foams. This work shows the relationship between the mechanical, thermal, and application properties of the obtained PUR composites depending on the modification of the filler used during synthesis.

Renewable lignin-based surfactant modified layered double hydroxide and its application in polypropylene as flame retardant and smoke suppression

A novel and environmentally friendly lignin-based surfactant sodium lignosulfonate (SLS) modified layered double hydroxide (LDH) flame retardant (LDH-LS) was fabricated via co-precipitation method, and subsequently incorporated into polypropylene (PP) matrix to obtain the PP and LDH-LS composites (PP/LDH-LS) by melt blending method. The XRD, FT-IR and XPS results indicated that SLS had successfully modified LDH by adsorbing on the surface of the LDH nanosheet. The WCA and SEM results revealed that the hydrophobic property of LDH-LS had been evidently improved, and it displayed a more homogeneous dispersion than virgin LDH in the PP matrix. Furthermore, cone calorimetry tests (CCT) illustrated that the peak heat release rate (PHRR), total heat release (THR), and total smoke release (TSR) of PP/LDH-LS composites exhibited declines of 62.9%, 25.1%, and 43.3% compared with those of Neat PP, respectively. Besides, the PP/LDH-LS achieved a LOI value of 29.4% and a UL-94 V-0 rating, whereas the PP/LDH showed only a LOI value of 25.2% and a UL-94 V-2 rating at 20 wt% loading. These improvements of flame retardant properties can be attributed to that the well-dispersed LDH-LS and synergistic flame retardancy between LDH and SLS.

Synthesis and Thermo-Mechanical Study of Epoxy Resin-Based Composites with Waste Fibers of Hemp as an Eco-Friendly Filler

The synthesis, thermal, and mechanical properties of epoxy resin composites incorporating waste fibers of hemp were studied. Five different systems with increasing quantity of the eco-filler were obtained. For the synthesis of polymeric materials, the commercial epoxy resins Epidian^® 5 and triethylenetetramine (TETA) were applied as crosslinking agents. The composites were obtained based on the polyaddition reaction of an amine group with an epoxide ring. ATR/FT-IR (Attenuated Total Reflection-Fourier Transform Infrared) analysis was used to confirm the chemical structure of the composites and the course of curing processes. Moreover, the influence of the eco-friendly components on the mechanical properties was determined, while thermal properties of the materials were investigated by thermogravimetry analysis (TGA) and differential scanning calorimetry (DSC). Dynamic mechanical studies (DMA) and Shore hardness tests of the obtained polymers were also carried out. The DSC curves and DMA analysis revealed that all materials were characterized by a similar glass transition range. Furthermore, the DMA and hardness measurements of the composites demonstrated an increasing elasticity with the increase in the amount of eco-filler present in the compositions.

Effectiveness assessment of TiO2-Al2O3 nano-mixture as a filler material for improvement of packaging performance of PLA nanocomposite films

The main objective of this study was to assess the effectiveness of TiO2-Al2O3 nano-mixture used as filler in improving packaging films performance. Polylactic acid/titanium dioxide (PLA/TiO2), polylactic acid/alumina (PLA/Al2O3) and polylactic acid/TiO2-Al2O3 (PLA/TiO2-Al2O3) nanocomposite films were successfully prepared via melt mixing process and thoroughly characterized by FTIR spectroscopy, X-ray diffraction (XRD), UV–vis spectroscopy, scanning electron microscopy (SEM), atomic force microscopy (AFM), thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The properties such as heat resistant, barrier, mechanical and antimicrobial properties, required for food packaging have also been investigated. As compared to the neat PLA film, the developed PLA nanocomposites have displayed superior properties particularly the PLA/ TiO2-Al2O3 nanocomposite film. This resulted material has showed a 22 °C increase in its thermal stability versus 14 and 2 °C in the cases of PLA/TiO2 and PLA/Al2O3 respectively, and a 54% reduction of its water vapor permeability in comparison with 47% for PLA/TiO2 and 39% for PLA/Al2O3. In addition, the PLA/TiO2-Al2O3 had a significant enhancement of its mechanical properties. Its Young modulus increased by 102% unlike 23.60% for the PLA/TiO2 and 44.66% for the PLA/Al2O3. It was also noticed that this nanocomposite film demonstrated stronger antibacterial activity than the two others. The bacterial growth inhibition effect of TiO2-Al2O3 nano-mixture against Pseudomonas aeruginosa and Escherichia coli bacteria was more effective than that of its two constituents.

Rigid Polyurethane Foams Based on Bio-Polyol and Additionally Reinforced with Silanized and Acetylated Walnut Shells for the Synthesis of Environmentally Friendly Insulating Materials

Rigid polyurethane (PUR) foams produced from walnut shells-derived polyol (20 wt.%) were successfully reinforced with 2 wt.% of non-treated, acetylated, and silanized walnut shells (WS). The impact of non-treated and chemically-treated WS on the morphology, mechanical, and thermal characteristics of PUR composites was determined. The morphological analysis confirmed that the addition of WS fillers promoted a reduction in cell size, compared to pure PUR foams. Among all the modified PUR foams, the greatest improvement of mechanical characteristics was observed for PUR foams with the addition of silanized WS-the compressive, flexural, and impact strength were enhanced by 21, 16, and 13%, respectively. The addition of non-treated and chemically-treated WS improved the thermomechanical stability of PUR foams. The results of the dynamic mechanical analysis confirmed an increase in glass transition temperature and storage modulus of PUR foams after the incorporation of chemically-treated WS. The addition of non-treated and chemically-treated WS did not affect the insulating properties of PUR foams, and the thermal conductivity value did not show any significant improvement and deterioration due to the addition of WS fillers.

Tailored Lignocellulose-Based Biodegradable Matrices with Effective Cargo Delivery for Crop Protection

Controlled release and targeted delivery of agrochemicals are crucial for achieving effective crop protection with minimal damage to the environment. This work presents an innovative and cost-effective approach to fabricate lignocellulose-based biodegradable porous matrices capable of slow and sustained release of the loaded molecules for effective crop protection. The matrix exhibits tunable physicochemical properties which, when coupled with our unique "wrap-and-plant" concept, help to utilize it as a defense against soil-borne pests while providing controlled release of crop protection moieties. The tailored matrix is produced by mechanical treatment of the lignocellulosic fibers obtained from banana plants. The effect of different extents of mechanical treatments of the lignocellulosic fibers on the protective properties of the developed matrices is systematically investigated. While variation in mechanical treatment affects the morphology, strength, and porosity of the matrices, the specific composition and structure of the fibers are also capable of influencing their release profile. To corroborate this hypothesis, the effect of morphology and lignin content changes on the release of rhodamine B and abamectin as model cargos is investigated. These results, compared with those of the matrices developed from non-banana fibrous sources, reveal a unique release profile of the matrices developed from banana fibers, thereby making them strong candidates for crop protection applications.

Tensile Properties and Microstructure of Single-Cellulosic Bamboo Fiber Strips after Alkali Treatment

The study systematically explored the effect of alkali concentration and soaking time on the microstructure and tensile properties of single-cellulosic Buluh Semantan. Scanning electron microscopy and tensile tests were conducted to determine the effects of different alkali treatments on the properties of the single-cellulosic bamboo fibers. In particular, the effects of NaOH concentration and soaking time on the tensile properties of the single-cellulosic bamboo fiber were investigated. The single-cellulosic bamboo fiber was immersed in 2, 4, 6, and 8 wt.% aqueous NaOH solutions for soaking times of 1, 3, 6, 12, 18, and 24 h. The tensile properties of the fiber increased after each alkali treatment. The alkali concentration and soaking time significantly affected the fiber properties. The ultimate tensile strength of the single-cellulosic Buluh Semantan treated with 2 wt.% NaOH for 12 h decreased to 214 MPa relative to the fibers that experienced water retting. The highest tensile strength herein was 356.8 MPa for the single-cellulosic fiber that was soaked for 12 h in 4 wt.% NaOH. Comparatively, the tensile strength of the single-cellulosic bamboo fiber that was soaked for 12 h in 8 wt.% NaOH was 234.8 MPa. The tensile modulus of the single-cellulosic fiber was 12.06 GPa after soaking in 8 wt.% NaOH for 18 h, indicating that a strong alkali treatment negatively affected the stiffness and suitability for use of the fibers in applications. The topography of the fiber surface became much rougher after the alkali treatments due to the removal of hemicellulose and other surface impurities. The alkali treatments substantially changed the morphology of the fiber surface, suggesting an increase in wettability.

Effects of Chemically Treated Eucalyptus Fibers on Mechanical, Thermal and Insulating Properties of Polyurethane Composite Foams

In this work, rigid polyurethane (PUR) foams were prepared by incorporating 2 wt% of eucalyptus fibers. The eucalyptus fibers were surface-modified by maleic anhydride, alkali, and silane (triphenylsilanol) treatment. The impact of the modified eucalyptus fibers on the mechanical, thermal, and fire performances of polyurethane foams was analyzed. It was observed that the addition of eucalyptus fibers showed improved mechanical and thermal properties and the best properties were shown by silane-treated fibers with a compressive strength of 312 kPa and a flexural strength of 432 kPa. Moreover, the thermal stability values showed the lowest decline for polyurethane foams modified with the silane-treated fibers, due to the better thermal stability of such modified fibers. Furthermore, the flame resistance of polyurethane foams modified with the silane-treated fibers was also the best among the studied composites. A cone calorimetry test showed a decrease in the peak of heat release from 245 to 110 kW∙m⁻² by the incorporation of silane-treated fibers. Furthermore, total heat release and total smoke release were also found to decrease remarkably upon the incorporation of silane-treated fibers. The value of limiting oxygen index was increased from 20.2% to 22.1%. Char residue was also found to be increased from 24.4% to 28.3%. It can be concluded that the application of chemically modified eucalyptus fibers has great potential as an additive to incorporate good mechanical, thermal, and fire properties in rigid polyurethane foams.

Bio-degumming of banana fibers using eco-friendly crude xylano-pectinolytic enzymes

In this study, the efficacy of xylano-pectinolytic enzymes in scouring of banana fibers has been reported. Maximum efficiency of bioscouring was recorded using xylanase and pectinase doses of 15 and 4.8 IU, respectively (produced by a bacterial isolate) at a material-to-liquor proportion of 1:25 having 8.5 pH, treatment time of 1 h, speed of 50 rpm, temperature 50 °C, 3 mM EDTA and 1% Tween-80, with maximum sugar release, enhanced fiber water absorbing power and the finest optical characteristics. Enzymatic treatment resulted in 13.27% increase in whiteness, 16.14% increase in brightness and 8.63% decrease in yellowness as compared to raw banana fibers. The bioscouring also resulted in 50% reduction in scouring chemicals, in order to achieve the similar optical characteristics as obtained by the chemically treated fibers with 100% scouring and bleaching. It decreased the consumption of environment polluting chemicals and energy. Therefore, this has proven to be an environment safe method for removing the non-cellulosic impurities. This is the first report mentioning the scouring of banana fibers using xylano-pectinolytic enzymes.

Environmental Degradation of Plastic Composites with Natural Fillers-A Review

Polymer composites are widely used modern-day materials, specially designed to combine good mechanical properties and low density, resulting in a high tensile strength-to-weight ratio. However, materials for outdoor use suffer from the negative effects of environmental factors, loosing properties in various degrees. In particular, natural fillers (particulates or fibers) or components induce biodegradability in the otherwise bio inert matrix of usual commodity plastics. Here we present some aspects found in recent literature related to the effect of aggressive factors such as temperature, mechanical forces, solar radiation, humidity, and biological attack on the properties of plastic composites containing natural fillers.

The Effect of Alkalization on Carboxymethil Cellulose Synthesis from Stem and Peel Cellulose of Banana

BACKGROUND:

North Sumatra is one of the regions in Indonesia that produce bananas. Banana stems and peels contain cellulose and it can be isolated in nanofiber form. Carboxymethylcellulose is a cellulose derivative that undergoes an alkalization and etherification process

AIM:

This research was conducted to evaluate the alkalization effect on synthesis of carboxymethyl cellulose from stem and peel cellulose of banana.

METHODS:

Stem and peel of banana was extracted with NaOH 17.5% and the extract was synthesized to carboxymethyl cellulose (CMC). The synthesis of CMC was beginning with alkalization process in variation of NaOH concentration and the reaction was then etherificated with sodium monochloroacetate. CMC was characterized by FTIR and DS values were determined.

RESULTS:

FTIR spectra of synthesized CMC had different pattern compared to cellulose. It showed that an etherification reaction had been occurred in the cellulose compound. Spectra of CMC with variation in alkali concentration was not much different from one another. The synthesized CMC from stem and peel cellulose of banana had different degree of substitution (DS) values due to variate concentration of NaOH in alkalization.

CONCLUSON:

Alkalization on CMC synthesis affects the DS value of synthesized CMC. The increase DS value is proportional to the rise in NaOH concentration even though there is a boundary concentration to obtain the optimum DS value.

Bioactive potential of fruit and vegetable wastes

Fruits and vegetables are essential for human nutrition, delivering a substantial proportion of vitamins, minerals, and fibers in our daily diet. Unfortunately, half the fruits and vegetables produced worldwide end up as wastes, generating environmental issues caused mainly by microbial degradation. Most wastes are generated by industrial processing, the so-called by-products. These by-products still contain many bioactive compounds post-processing, such as macronutrients (proteins and carbohydrates) and phytochemicals (polyphenols and carotenoids). Recently, the recovery of these bioactive compounds from industry by-products has received significant attention, mainly due to their possible health benefits for humans. This chapter focuses on the bioactive potential of fruit and vegetable by-products with possible applications in the food industry (functional foods) and in the health sector (nutraceuticals).

Fique Fabric: A Promising Reinforcement for Polymer Composites

A relatively unknown natural fiber extracted from the leaves of the fique plant, native of the South American Andes, has recently shown potential as reinforcement of polymer composites for engineering applications. Preliminary investigations indicated a promising substitute for synthetic fibers, competing with other well-known natural fibers. The fabric made from fique fibers have not yet been investigated as possible composite reinforcement. Therefore, in the present work a more thorough characterization of fique fabric as a reinforcement of composites with a polyester matrix was performed. Thermal mechanical properties of fique fabric composites were determined by dynamic mechanical analysis (DMA). The ballistic performance of plain woven fique fabric-reinforced polyester matrix composites was investigated as a second layer in a multilayered armor system (MAS). The results revealed a sensible improvement in thermal dynamic mechanical behavior. Both viscoelastic stiffness and glass transition temperature were increased with the amount of incorporated fique fabric. In terms of ballistic results, the fique fabric composites present a performance similar to that of the much stronger Kevlar^TM as an MAS second layer with the same thickness. A cost analysis indicated that armor vests with fique fabric composites as an MAS second layer would be 13 times less expensive than a similar creation made with Kevlar™.

Green carboxymethyl cellulose-silver complex versus cellulose origins in biological activity applications

This article deals with evaluating the role of cellulose origin, from wood and non-wood, on preparing green CMC-Ag complex as biological active agent. Viscose pulp as well as bagasse and rice straw pulps were used in preparation of CMCs, followed by complexation with AgNO_3. The complex structure (free-Ag, IR-spectra and TGA), morphology (TEM), antibiological and anti-tumor activities were studied. The data revealed that, the main interaction between CMC and silver is occurred via carboxylate groups and ether link of 1ry alcohol, with formation stable 5-membered ring structure. For the case of RS-based CMC-Ag complex the interaction between COO groups and silica included RS is also possible, via hydrogen bonds. These complexes have anti-biological especially towards gram positive bacteria (B.subtilis, NCID-3610), and uni- and multi cellular fungi. AgNPs from viscose (VCMC-Ag complex) has relatively higher anti-tumor activity for breast cancer MCF-7 in vitro than bagasse-based CMC-Ag complex (BCMC-Ag complex) with IC₅₀ 128μg/ml (as Ag). It is interesting to note that; viscose-based CMC-Ag complex (VCMC-Ag) has higher efficient behaviour as bioactive agent than literature reported agents, e.g., Pyridine derivative (∼300μg/ml).

Preparation and Properties of a Novel Microcrystalline Cellulose-Filled Composites Based on Polyamide 6/High-Density Polyethylene

In the present study, lithium chloride (LiCl) was utilized as a modifier to reduce the melting point of polyamide 6 (PA6), and then 15 wt % microcrystalline cellulose (MCC) was compounded with low melting point PA6/high-density polyethylene (HDPE) by hot pressing. Crystallization analysis revealed that as little as 3 wt % LiCl transformed the crystallographic forms of PA6 from semi-crystalline to an amorphous state (melting point: 220 °C to none), which sharply reduced the processing temperature of the composites. LiCl improved the mechanical properties of the composites, as evidenced by the fact that the impact strength of the composites was increased by 90%. HDPE increased the impact strength of PA6/MCC composites. In addition, morphological analysis revealed that incorporation of LiCl and maleic anhydride grafted high-density polyethylene (MAPE) improved the interfacial adhesion. LiCl increased the glass transition temperature of the composites (the maximum is 72.6 °C).

Recent progress in cellulose nanocrystals: sources and production

Cellulose nanocrystals, a class of fascinating bio-based nanoscale materials, have received a tremendous amount of interest both in industry and academia owing to its unique structural features and impressive physicochemical properties such as biocompatibility, biodegradability, renewability, low density, adaptable surface chemistry, optical transparency, and improved mechanical properties. This nanomaterial is a promising candidate for applications in fields such as biomedical, pharmaceuticals, electronics, barrier films, nanocomposites, membranes, supercapacitors, etc. New resources, new extraction procedures, and new treatments are currently under development to satisfy the increasing demand of manufacturing new types of cellulose nanocrystals-based materials on an industrial scale. Therefore, this review addresses the recent progress in the production methodologies of cellulose nanocrystals, covering principal cellulose resources and the main processes used for its isolation. A critical and analytical examination of the shortcomings of various approaches employed so far is made. Additionally, structural organization of cellulose and nomenclature of cellulose nanomaterials have also been discussed for beginners in this field.

Microcrystalline cellulose: Isolation, characterization and bio-composites application-A review

Considering its widespread usage in various fields, such as food, pharmaceutical, medical, cosmetic and polymer composites industries, microcrystalline cellulose (MCC) is becoming impellent due to increasing demand of alternatives to non-renewable and scarce fossil materials. Although it still suffers from some drawbacks, MCC has recently gained more interest owing to its renewability, non-toxicity, economic value, biodegradability, high mechanical properties, high surface area and biocompatibility. New sources, new isolation processes, and new treatments are currently under development to satisfy the increasing demand of producing new types of MCC-based materials on an industrial scale. Therefore, this review assembles the current knowledge on the isolation of MCC from different sources using various procedures, its characterization, and its application in bio-composites. Challenges and future opportunities of MCC-based composites are discussed as well as obstacles remaining for their extensive uses.

Recent advances in cellulose and chitosan based membranes for water purification: A concise review

Recently membrane technology has emerged as a new promising and pervasive technology due to its innate advantages over traditional technologies such as adsorption, distillation and extraction. In this article, some of the recent advances in developing polymeric composite membrane materials for water purification from natural polysaccharide based polymers namely cellulose derivatives and chitosan are concisely reviewed. The impact of human social, demographic and industrial evolution along with expansion through environment has significantly affected the quality of water by pollution with large quantities of pesticides, minerals, drugs or other residues. At the forefront of decontamination and purification techniques, we found the membrane materials from polymers as a potential alternative. In an attempt to reduce the number of technical polymers widely used in the preparation of membranes, many researchers have reported new solutions for desalination or retention of organic yeasts, based on bio renewable polymers like cellulose derivatives and chitosan. These realizations are presented and discussed in terms of the most important parameters of membrane separation especially water flux and retention in this article.

Evaluation of Castor Oil Cake Starch and Recovered Glycerol and Development of "Green" Composites Based on Those with Plant Fibers

Continuous efforts are being made in some countries for the recovery of crude glycerin (RG/CG) and castor oil cake (COC), the two byproducts of biodiesel production. These are expected to help, not only in addressing environmental safety, but also in adding value to those byproducts, which otherwise may go to waste. Finding ways to utilize those byproducts underlines the main objective of this study. This paper presents the evaluation of (i) COC, glycerin and banana and sugarcane fibers for moisture content; (ii) COC for structural and thermal properties; and (iii) CG for its chemical characteristics. The possibility of using COC and CG with the selected fibers as reinforcement in the development of bio-composites is attempted through thermo-molding. Results revealed enhanced mechanical properties for these composites. The obtained results are discussed in terms of the observed morphology.

Failure Progress of 3D Reinforced GFRP Laminate during Static Bending, Evaluated by Means of Acoustic Emission and Vibrations Analysis

The work aimed to assess the failure progress in a glass fiber-reinforced polymer laminate with a 3D-woven and (as a comparison) plain-woven reinforcement, during static bending, using acoustic emission signals. The innovative method of the separation of the signal coming from the fiber fracture and the one coming from the matrix fracture with the use of the acoustic event's energy as a criterion was applied. The failure progress during static bending was alternatively analyzed by evaluation of the vibration signal. It gave a possibility to validate the results of the acoustic emission. Acoustic emission, as well as vibration signal analysis proved to be good and effective tools for the registration of failure effects in composite laminates. Vibration analysis is more complicated methodologically, yet it is more precise. The failure progress of the 3D laminate is "safer" and more beneficial than that of the plain-woven laminate. It exhibits less rapid load capacity drops and a higher fiber effort contribution at the moment of the main laminate failure.