ABSTRACTIn the current paper, the thermal insulation material from the wool of sheep grown in Lithuania is analyzed. Three types of thermal insulation material were produced: horizontal orientations, corrugated from the individual layer obtained, and corrugated from individual mats. The 50 mm thick products were prepared and their main performance characteristics were evaluated: thickness changes, thermal conductivity, tensile strength, short-term water absorption, and flammability. Changes in the thickness of the materials were determined under different loads, and dependences on the density of the material were obtained. Thermal conductivity was measured for products of different densities, evaluated separately for horizontal orientation and corrugated products, and density dependences were obtained. Tensile strength was determined along and across the direction of formation for relatively different types of products. For all types of products, the short-term water absorption of the specimens was determined by partial immersion in water, and the results were compared. During the flammability tests, the flame propagation time on the specimen surface and the fact of incineration after removal of the flame source were determined for all types of specimens.

ABSTRACTTo diminish the environmental impacts instigated by plastics, investigators recommended bioplastics. In the current work, an attempt is made to develop sustainable bioplastics from waste plants. Cellulose was extracted from the wood of Prosopis juliflora. The Prosopis juliflora wood was cut and ground into powder. The powder was washed with water and subjected to several chemical treatments to extract the cellulose. The bioplastic film samples were produced using it. Six different samples were prepared by varying the composition of cellulose, gelatin, citric acid, and glycerol. Several tests were carried out on samples developed as per ASTM standards, and the results were compared with the existing bioplastics. The test results indicated that sample 1 has a maximum tensile strength of 7.73 MPa. The average bursting strength of the bioplastic film is 12.44 kg/cm2, which is better than the other bioplastics reported in the literature. The average biodegradability of developed bioplastic films is approximately 59.43%. The results revealed that the Prosopis juliflora cellulose-based bioplastics would be a better substitute for conventional plastics.

ABSTRACTChitin is one of the most abundant biopolymers in nature. Herein, we report the successful preparation of chitin nanofibers (ChNFs) from shrimp shell waste using a partial deacetylation process with NaOH and high-speed blending. The effects of the deacetylation reaction with NaOH concentrations (0–40 wt%) on the degree of acetylation (DA), crystallinity, zeta potential, thermal stability, and morphology of the ChNFs were investigated. With the more aggressive deacetylation reaction (higher NaOH concentration), ChNFs had the lower DA, crystallinity degree, and thermal stability, and their widths and lengths became smaller and shorter. The presence of amino groups in the chitin molecule caused by deacetylation generated repulsive forces with aids of acetic acid, efficiently leading to the individualization of ChNFs using high-speed blending. The individualized ChNFs deacetylated with 30 wt% NaOH had an average width of 8.07 ± 1.80 nm and length of less than 500 nm, whereas bundles of aggregated fibers with widths in the range of 30–100 nm and lengths of up to several μm were extracted from chitin without deacetylation. Additionally, the deacetylation with 40 wt% NaOH completely converted chitin to chitosan. The ChNFs could be efficiently used for composites, biomaterials, and packaging applications.

ABSTRACTMost commercial products of dehulled hemp seeds frequently include dark green remnants of shells. The entire removal of shell particles including seed coats and pericarp pieces can improve the quality of hempseed-based products. In this study, the structural characteristics of fruit walls (pericarp) and seed coats of Cannabis sativa were examined using scanning electron microscopy. The pericarp was comprised of three distinct zones, exo-, meso-, and endocarp. The exocarp and the mesocarp were tightly fused to form a thick layer. The endocarp was characterized by its sclerenchymatous columnar cells, which contained greatly thickened and multi-porous cell walls. On the other hand, the seed coats were comprised of two leathery coats, the outer and inner coats. The outer seed coat was a conspicuous layer with a reticular-shaped structure like a net. However, the three-layered inner seed coat was composed of two thin layers (inner seed coat 2, inner seed coat 3) and a large rectangular cell layer (inner seed coat1) at the lower position. This work provides a better understanding of the structural characteristics of hemp shells. It will lead to the improvement of dehulling machinery of hempseed and help ensure stringent quality control of hempseed-based products.

ABSTRACTThe brittle nature of concrete sometimes makes it challenging for many critical applications. Research has indicated that including discrete short-length, closely spaced fibers in concrete could improve its ductility and act as a crack arrester. As Bangladesh is the prime producer of natural fiber jute, this research aimed to improve the concrete property with this biomaterial. Laboratory work evaluated the mechanical property and shrinkage cracking resistance of jute fiber reinforced concrete with different fiber fractions (viz. 0.1%, 0.2%, 0.3%, and 0.4% by concrete volume) and lengths. The fibers were designated J20 and J25 for 20 and 25-mm lengths, respectively. A portion of the fiber was treated with alkali before using in concrete to improve its property. Jute Fiber Reinforced Concrete (JFRC) was analyzed qualitatively, semi-quantitatively, and quantitatively for compressive, splitting tensile strength, and plastic shrinkage cracking. It was found that the compressive and splitting tensile strengths can be improved by 7% and 25%, respectively. Furthermore, the bio-fiber had a significant influence on shrinkage crack control. In a controlled environment, up to 61% crack area and 62% maximum crack width reduction were achieved. Overall, jute fiber was found to be a sustainable biomaterial for concrete construction in an arid region.

ABSTRACTWith the technological advances in wearable and portable electronic devices, the demands for associated technologies including flexible energy storage devices increase. Among many types of energy storage devices, flexible supercapacitors (FSCs) are highly attractive in comparison with others as they exhibit high power density, high storage density, and mechanical stability. In particular, carbon nanotubes (CNTs) are being widely used as the electrode materials for FSCs, owing to their mechanical strength and outstanding electrical performance. Herein, we classified CNT-based FSCs according to the structural types of CNTs and the materials incorporated. The unique structures and properties of the three types of CNTs (single-walled CNTs (SWCNT), double-walled CNTs (DWCNT), and multi-walled CNTs (MWCNT)) are compared and the mechanisms of FSCs are discussed. Finally, a summary of the overall electrochemical properties and current development of the reported FSC electrodes based on SWCNT, DWCNT, and MWCNT are presented thoroughly.

ABSTRACTIn this study, the compression molding technique was used to fabricate hybrid composites using different wt.% of the glass and ramie fibers in different stacking sequences. The physical (density, water absorption, and wear resistance) and mechanical (tensile strength, hardness, and impact strength) and morphology studies were performed for the glass and ramie fibers and the effect of stacking sequencing was studied. A technique for order of preference by similarity to the ideal solution model was used to determine the optimal reinforcement composition in the hybrid composites. The stacking sequence played a crucial role in the physical and mechanical characteristics of the hybrid composites. The GRG (stacking sequence: Glass (4 wt.%)-Ramie (4 wt.%)-Glass(4 wt.%)) hybrid composite showed optimal characteristics; tensile strength: 114 MPa, hardness: 41 HV, impact energy: 3.5 J m−1, void content: 1.09% and wear: 63 μm. However, if glass fibers were sandwiched between the ramie fiber layer, the composite showed lower physical and mechanical characteristics; tensile strength: 72 MPa, hardness: 28 HV, impact energy: 3 J m−1. The glass fiber reinforced composites (GG and GGG) exhibited better water absorption characteristics. The RRR composite’s impact strength was comparable with the GGG composites due to the stacking of the composites. Moreover, the glass fiber composites stacking (RR to RGR) exhibited lower tensile strength than ramie fiber composites stacking (GG to GRG). The microstructural analysis of the fractured composite surface revealed voids, de-lamination, interfacial bonding of the fibers with the matrix, fiber pull-out, and matrix distribution.

ABSTRACTIn this study, copper nanoparticles were synthesized from Trapa natans L. shells and loaded within polyamide-12 for use as an adsorbent. The synthesized nanocomposite was used for the first time to remove toxic methyl orange and brilliant green dye molecules from synthetic aqueous solutions. In order to characterize the plant-based nanocomposite, its functional groups, surface texture, elemental composition, structure, surface area, and crystallinity were determined. Adsorption efficiency was found to be affected by factors like pH (2–10), time (5–240 min.), and temperature (288–308 K). It was at pH 6 that the adsorbent reached the point of zero charge. During the adsorption process, electrostatic attraction played an influential role. Adsorption isotherms and kinetics data were well-fitted by Langmuir isotherms and pseudo-second-order models, respectively. A maximum adsorption capacity of 166.60 mg/gm was calculated for 93.90% methyl orange removal and 55.24 mg/gm for 97.30% brilliant green removal. The adsorption process was endothermic, spontaneous, and physical. The rapid desorption of dye molecules confirms the potential, and practicality of the nanocomposite as a promising adsorbent for decolorizing colored wastewater on an industrial scale.

ABSTRACTWith increased awareness of the environmental issues associated with synthetic polymers, eco-friendly biodegradable materials are in high demand. This study assesses sisal fabrics’ physical, structural and thermal properties and a blend of sisal and cotton fabrics for their suitability for use with cow nubuck leather in leather product applications. All the chosen sisal fabrics were found to have mechanical properties comparable to or even better than cow nubuck leather. The tensile strength of sisal fabric is far greater than cow nubuck leather. The strength of sisal fibers ranges from 400 to 700 Mpa, whereas cow nubuck leather ranges from 10 to 40 Mpa. On the other hand, cow nubuck leather outperforms all other fabrics in terms of elongation percentage. Scanning electron microscopic analysis provided convincing evidence for characteristic fiber patterns in the individual fiber bundles (yarn) and their blend fiber composition of sisal fabrics. Sisal fabrics have a higher thermal stability than cow nubuck leather, with a degradation temperature of 230°C. According to the findings of this study, we can say that the selected sisal fabrics can be used to make leather lifestyle products.

ABSTRACTIn this study, an attempt is made to check whether a hybrid composite made up of both synthetic and natural fibers (Carbon and Cordia Dichotoma respectively) can be made bio-degradable, at least to some extent, without much compromising on the mechanical properties. Hybrid composites were prepared by reinforcing alkali treated Cordia dichotoma and carbon fibers into epoxy resin using hand lay-up method. By varying the number of layers of fibers in the composite specimen and fixing 20% fiber weight for all composites, nine distinct combinations of specimens were prepared. The maximum tensile strength of 386.68 MPa, flexural strength of 647.08 MPa, and impact energy of 4.82 J were obtained for composites produced with pure carbon fiber, whereas hybrid composite exhibit tensile strength of 367.76 MPa, flexural strength of 646.41MPa and impact energy of 4.74 J. The interfacial bonding between the fibers and matrix of tested specimens was studied using a scanning electron microscope (SEM), as well as the arrangement of fibers within the matrix for the manufactured composite. Thermogravimetric analysis (TGA) was used to investigate thermal stability, and it was found that it was thermally stable up to 415°C. 9. Crystallinity value increases from 20% carbon fiber to 20% alkali fiber.

ABSTRACTThis experimental study aims to explore natural lignocellulosic fibers from Jenfokie and Doby plants. The effect of the fiber (water-retted and non-retted) extraction methods on physical, mechanical, thermal, chemical, and crystallinity properties were experimentally investigated for fibers collected from the eastern highlands of Ethiopia. The chemical composition (cellulose, hemicellulose, lignin, extractives, etc.) was determined after different treatment processes. The tensile strength maximum of up to 72 cN/tex and 56 cN/tex, and cellulose content up to 85% and 81% were obtained for Jenfokie and Doby retted extracted fibers, respectively. There was small difference lignin extracted by Klason method and the alkaline hydrogen peroxide (APH) method. Each step-wise extracted fiber was characterized to cognize the intrinsic changes during the multi-step extraction process. The diameters were determined by Optical Microscope (OM), the removal of non-cellulosic materials by Fourier Transform Infrared (FT-IR) spectroscopy, the thermal stability (up to 375°C) by thermogravimetry (TGA), and the crystallinity index (up to 73%) by using X-ray Diffraction (XRD). An improvement in cellulose content, density, moisture absorption, tensile strength, thermal stability, and crystallinity of Jenfokie (unstudied or new) and Doby plant retted fibers would be promising for composite and textile materials.

ABSTRACTExtensive research has been conducted during 20th century to discover renewable natural polymers that are sustainable. Cellulose represents one such biomaterial which is abundant, renewable, and biodegradable. Both plant and microbial biomass can be processed to make cellulose. Bacterial cellulose (BC) is a prospective natural polymer produced by certain bacteria during their growth phase. BC is hydrophilic biopolymer, fibrous (20–100 nm diameter), and biocompatible. In contrast to plant cellulose, BC has the benefit of being in form, which is both, highly crystalline and extremely pure. This review provides a crisp summary of the synthesis and functionalization of BC, and its applications in the fields of biomedicine and the environment.

ABSTRACTIn order to prepare fiber-type nanohybrid composites for electrochemical and antimicrobial applications, polypyrrole was combined with carboxymethylcellulose and multiwalled carbon nanotubes (PPy/CMC/MWCNTS). These composite materials were synthesized using ultrasonication and in situ polymerization. By using analytical methods, the structure and morphology of the synthesized nanohybrid composite material were confirmed. Slurry of fiber-type PPY/CMC/MWCNT composites synthesized in ethanol was deposited as a thin-uniform layer with conductive nafion (5% ethanolic solution of nafion) binder. Based on electrochemical measurements in a phosphate buffer medium, Sb3+ ions have linear responses between 0.1 nM and 0.01 mM, which is known as linear dynamic range (LDR). A sensor’s sensitivity (22.4304 µAµM−1cm−2) is calculated using the LDR slope by considering the GCE surface area (0.0316 cm2). A signal-to-noise ratio of 3 is used to estimate the lower limit of detection which is equal to 96.82 ± 4.84 pM. Moreover, the antibacterial activity of the obtained polypyrrole/carboxymethylcellulose/MWCNT composite has also been evaluated “against Gram-positive bacteria B. subtilis along with S. aureus, as well as Gram-negative bacteria, P. aeruginosa along with Escherichia coli by utilizing” autoclave of agar media. In electrochemical analysis, the proposed Sb3+ cationic sensor exhibits appreciable reproducibility, response time, stability, and outstanding outcome in analysis of real samples. In the field of metal ion sensor, this reliable method might be prospective in the recent future.

ABSTRACTHigh specific strength and modulus of fiber-reinforced polymer composites tend to be the reason for replacing many metallic structures. Synthetic fiber (E-glass) becomes a risk for health and leads to cancer. Ficus Carica (FC) bark fiber undergoes comprehensive characterization analysis such as Thermal Gravimetric Analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Physical analysis and Chemical analysis. Bark of Ficus Carica plant is taken and the fibers are extracted. It is essential to study microstructure, chemical composition and mechanical properties of the fiber to utilize these lignocellulosic fibers as a reinforcement material in polymer composites. The results of this investigation are very encouraging for its applications to be used in industries for manufacturing fiber composites. FC Bark Fiber (FCBF) contains high cellulose content such as 63.17% and very little wax (0.42%). Good thermal stability of the fiber up to 225°C was produced from thermogravimetric analysis, which is well indicated within its polymerization process temperature. FCBF’s exhibit suitable properties that are to be used as natural reinforcement material.

ABSTRACTThe specific properties and availability of banana pseudo-trunk fibers make them a promising alternative for the development of green composites. However, the wide dispersion of their properties can hinder their use. In this study, the influence of the sampling area of the banana pseudo-trunk on the physical and mechanical properties of the fibers was evaluated. Prior to retting, the trunk was sampled longitudinally (bottom, middle and top) and transversely (periphery, intermediate and heart). Gravimetric tests were carried out and revealed variations in water absorption (347.1–517.4%), density (0.92–1.45 g.cm−3) and linear mass (25 -34tex). Tensile tests were also performed and showed a significant effect of fiber location on Young’s modulus (6.60–34.6GPa), tensile strength (91-350MPa) and elongation at the break (0.9–2.6%). Due to diameter scatter, variations of 42% were found for fibers in the same area. In a region, the physical properties increase from the periphery to the core, and the mechanical properties decrease in the same direction, except for elongation. The results of this study showed good agreement with those of other natural fiber types. However, we recommend the peripheral areas of the pseudo-trunk to extract reinforcing fibers from composites because of their low density (0.9 g.cm−3) and their high stiffness (34GPa).

ABSTRACTIn this study, we explore the dyeing properties of the extract of sappan wood natural dye for coloration of wool yarn to find the potential use of natural dyed wool yarn in the development of eco-friendly textiles. Different characterizations were used to know the chemistry of sappan wood dye and its interaction with metal salts and wool. Interestingly, we found that metal salts, which are called as mordants in reference to unmordanted dyed sample, play an important role in fixing the dye molecule on wool as well as in creating different shades with a variety of hues and tones. The typical color of fabric dyed with extracts of sappan wood without mordant varies from yellowish to red. Light yellowish shades were obtained in case of aluminum sulfate-mordanted samples, whereas yellowish shades were obtained in case of ferrous sulfate mordant. Light colorfastness of the premordanted dyed samples was relatively better than that of the unmordanted dyed samples. The wash fastness of all samples mordanted as well as unmordanted shows color change fairly good to good level, whereas the color staining on wool and cotton was found to be negligible.

ABSTRACTTo solve the problem of the grade evaluation of foreign fiber content in cotton, this paper divided the problem into multi-criteria decision-making field and proposed an interval-valued Pythagorean fuzzy set foreign fiber content grade evaluation method. Taking into account the various properties of foreign fibers, the multi-criteria evaluation of single foreign fiber content and comprehensive foreign fiber content is carried out to improve the quality of cotton textiles. Based on the Pythagorean fuzzy set, we used AHP and TOPSIS methods to determine the relevant weight information, combined with the grade evaluation index of foreign fiber content and the interval-valued Pythagorean fuzzy weighted average or geometric operators to construct a fiber multi-criteria decision model. Then, the evaluation index function is improved to make the score function more consistent with the facts, and the digitization and intelligence methods required for foreign fiber content detection and grade evaluation are developed. Further, an example is given to verify the feasibility and effectiveness of the model. In addition, the multi-criteria decision-making method adopted has high theoretical innovation and application value for the textile industry.

ABSTRACTThe inferior mechanical and water absorption properties of natural fibers are massive challenges to utilizing them for industrial applications. The study aims to enhance tensile strength, impact strength, water absorption, and degradation of sisal/polyester composites using glass and carbon fillers. Four fillers proportions (2.5 wt.%, 5 wt.%, 7.5 wt.%, 10 wt.%) and two sisal fiber proportions (20 wt.% and 30 wt.%) were taken to fabricate the composites. Experimentations were performed according to the ASTM standards. The fillers improved tensile and impact strength, water absorption, and degradation of the composites. Carbon-filled composites displayed better results than the corresponding glass-filled composites. Carbon fillers showed a maximum increment of 24.2% in tensile and 78.5% in impact strength for the dry 20/80 composites, and 14.7% in tensile and 57.3% in impact strength for the dry 30/70 composites. Moreover, carbon fillers reduced water absorption by 55.4% for the 20/80 composites and by 53.6% for the 30/70 composites. The highest values of tensile and impact strengths were obtained for the 5 wt.% carbon-filled 30/70 composite; whereas, the lowest water absorption was for the 10 wt.% carbon-filled 20/80 composite. The lowest degradation of 2% in tensile and impact strengths was exhibited for the 7.5 wt.% carbon-filled 20/80 composites.

ABSTRACTCotton fabric selection is a challenging task in the garment product design and development process, and the selection of optimal alternative under the presence of multiple decision criteria becomes complex, and hence it is considered as a multi-criteria decision-making (MCDM) problem. In addition, the selection process involves fuzziness and uncertainty. In this study, Pythagorean fuzzy sets (PFSs) are introduced to handle uncertain information. Elimination and choice translating reality (ELECTRE) is a well-known outranking method for solving MCDM problems. Therefore, we extend the ELECTRE method under the PFS environment, and a correlation-based closeness coefficient is proposed to compare Pythagorean fuzzy numbers (PFNs). This paper applies the proposed PF-ELECTRE approach in solving a practical case involving the ranking cotton fabrics. To exhibit the superiority and robustness of the suggested method, sensitivity analysis is performed to examine the impacts of weights variation, as well as a comparative analysis is carried out between the PF-ELECTRE with several existing MCDM methods. The research contributes to the advancement and development of outranking MCDM methods through a novel PF-ELECTRE approach that utilizes the weighted correlation coefficient. Moreover, the developed method can obtain reliable results and can be used to other textile domains.

ABSTRACTThe biodegradable characteristics and abundant availability of the fiber sources have gained the attention of various industries to produce natural fiber-based composites. As a sustainable alternative to the non-biodegradable fiber-based products, the natural composites provide a viable solution to reduce the environmental pollution caused by synthetic materials. This study developed rice straw particle (RSp) and Furcraea foetida (FF) fiber reinforced hybrid composite and investigated its physical and mechanical properties. The addition of 15 wt.% of RSp reduced the density of the test samples by 41.87% and its water absorption (WA) increased with the increase in fiber concentration. The composite with 5 wt.% and 15 wt.% of RSp showed maximum tensile strength (σt: 29.45 MPa) and modulus (σtm: 3.67 GPa), respectively. At 15 wt.% of RSp, the maximum flexural strength (σf: 43.12 MPa) and modulus (σfm: 2.09 GPa) was achieved and at 10 wt.% of RSp showed the highest impact strength (σi: 101.01 J/m). The σt (40.21%) and σf (7.76%) of the RSp reinforced composite were improved by the hybridization of FF (20 wt.%) fiber reinforcement.