Synthesis of Carboxymethyl Starch-Bio-Based Epoxy Resin and their Impact on Mechanical Properties

Thermal, mechanical, and morphological properties of oil palm cellulose nanofibril reinforced green epoxy nanocomposites

In this study, significant improvements in mechanical properties have been seen through the efficient inclusion of Oil Palm Cellulose Nanofibrils (CNF) as nano-fillers into green polymer matrices produced from biomass with a 28 % carbon content. The goal of the research was to make green epoxy nanocomposites utilizing solution blending process with acetone as the solvent with the different CNF loadings (0.1, 0.25, and 0.5 wt%). An ultrasonic bath was used in conjunction with mechanical stirring to guarantee that CNF was effectively dispersed throughout the green epoxy. The resultant nanocomposites underwent thorough evaluation, comparing them to unfilled green epoxy and evaluating their morphological, mechanical, and thermal behavior using a variety of instruments. Field-emission scanning electron microscopy (FE-SEM) was used to validate findings, which showed that the CNF were dispersed optimally inside the nanocomposites. The thermal degradation temperature (Td) of the nanocomposites showed a marginal decrement of 0.8 % in temperatures (from 348 °C to 345 °C), between unfilled green epoxy (neat) and 0.1 wt% of CNF loading. The mechanical test results, which showed a 13.3 % improvement in hardness and a 6.45 % rise in tensile strength when compared to unfilled green epoxy, were in line with previously published research. Overall, the outcomes showed that green nanocomposites have significantly improved in performance.

Developing multifunctional cellulose derivatives for environmental and biomedical applications: Insights into modification processes and advanced material properties

The growing bioeconomic demand for lightweight, eco-friendly materials with functional versatility and competitive mechanical properties drives the resurgence of cellulose as a sustainable scaffold for various applications. This review comprehensively scrutinizes current progressions in cellulose functional materials (CFMs), concentrating on their structure-property connections. Significant modification methods, including cross-linking, grafting, and oxidation, are discussed together with preparation techniques categorized by cellulose sources. This review article highlights the extensive usage of modified cellulose in various industries, particularly its potential in optical and toughening applications, membrane production, and intelligent bio-based systems. Prominence is located on low-cost procedures for developing biodegradable polymers and the physical-chemical characteristics essential for biomedical applications. Furthermore, the review explores the role of cellulose derivatives in smart packaging films for food quality monitoring and deep probes into cellulose's mechanical, thermal, and structural characteristics. The multifunctional features of cellulose derivatives highlight their worth in evolving environmental and biomedical engineering applications.

Green synthesis of Zn-doped TIO2 nanoparticles from Zanthoxylum armatum

Green synthesis is an easy, safe, and environmentally beneficial nanoparticle creation method. It is a great challenge to simultaneously improve the capping and stabilizing agent carrier separation efficiency of photocatalysts. Herein, Zn-doped Titanium dioxide (TiO2) nanoparticles with high exposure of 360 nm using a UV/visible spectrophotometer were prepared via a one-step hydrothermal decomposition method. A detailed analysis reveals that the electronic structures were modulated by Zn doping; thus, the responsive wavelength was extended to 600 nm, which effectively improved the visible light absorption of TiO2. We have optimized the different parameters like concentration, time, and temperature. The peak for TiO2 is located at 600 cm-1 in FTIR. A scanning electron microscope revealed that TiO2 has a definite shape and morphology. The synthesized Zn-doped TiO2NPs were applied against various pathogens to study their anti-bacterial potentials. The anti-bacterial activity of Zn-doped TiO2 has shown robust against two gram-ve bacteria (Salmonella and Escherichia coli) and two gram + ve bacteria (Staphylococcus epidermidis and Staphylococcus aureus). Synthesized Zn-doped TiO2 has demonstrated strong antifungal efficacy against a variety of fungi. Moreover, doping TiO2 nanoparticles with metal oxide greatly improves their characteristics; as a result, doped metal oxide nanoparticles perform better than doped and un-doped metal oxide nanoparticles. Compared to pure TiO2, Zn-doped TiO2 nanoparticles exhibit considerable applications including antimicrobial treatment and water purification.

Challenges associated with cellulose composite material: Facet engineering and prospective

Cellulose is the most abundant polysaccharide on earth. It has a large number of desirable properties. Its low toxicity makes it more useful for a variety of applications. Nowadays, its composites are used in most engineering fields. Composite consists of a polymer matrix and use as a reinforcing material. By reducing the cost of traditional fibers, it has an increasing demand for environment-friendly purposes. The use of these types of composites is inherent in moisture absorption with hindered natural fibers. This determines the reduction of polymer composite material. By appropriate chemical surface treatment of cellulose composite materials, the effect could be diminished. The most modern and advanced techniques and methods for the preparation of cellulose and polymer composites are discussed here. Cellulosic composites show a reinforcing effect on the polymer matrix as pointed out by mechanical characterization. Researchers tried their hard work to study different ways of converting various agricultural by-products into useful eco-friendly polymer composites for sustainable production. Cellulose plays building blocks, that are critical for polymer products and their engineering applications. The most common method used to prepare composites is in-situ polymerization. This help to increase the yields of cellulosic composites with a significant enhancement in thermal stability and mechanical properties. Recently, cellulose composites used as enhancing the incorporation of inorganic materials in multi-functional properties. Furthermore, we have summarized in this review the potential applications of cellulose composites in different fields like packaging, aerogels, hydrogels, and fibers.

Role of silica-based porous cellulose nanocrystals in improving water absorption and mechanical properties

Epoxy resins are important thermosetting polymers. They are widely used in many applications i.e., adhesives, plastics, coatings and sealers. Epoxy molding compounds have attained dominance among common materials due to their excellent mechanical properties. The sol-gel simple method was applied to distinguish the impact on the colloidal time. The properties were obtained with silica-based fillers to enable their mechanical and thermal improvement. The work which we have done here on epoxy-based nanocomposites was successfully modified. The purpose of this research was to look into the effects of cellulose nanocrystals (CNCs) on various properties and applications. CNCs have recently attracted a lot of interest in a variety of industries due to their high aspect ratio, and low density which makes them perfect candidates. Adding different amounts of silica-based nanocomposites to the epoxy system. Analyzed with different techniques such as Fourier-transformed infrared spectroscope (FTIR), thermogravimetric analysis (TGA) and scanning electronic microscopic (SEM) to investigate the morphological properties of modified composites. The various %-age of silica composite was prepared in the epoxy system. The 20% of silica was shown greater enhancement and improvement. They show a better result than D-400 epoxy. Increasing the silica, the transparency of the films decreased, because clustering appears. This shows that the broad use of CNCs in environmental engineering applications is possible, particularly for surface modification, which was evaluated for qualities such as absorption and chemical resistant behavior.

A Review on the Modification of Cellulose and Its Applications

The latest advancements in cellulose and its derivatives are the subject of this study. We summarize the characteristics, modifications, applications, and properties of cellulose. Here, we discuss new breakthroughs in modified cellulose that allow for enhanced control. In addition to standard approaches, improvements in different techniques employed for cellulose and its derivatives are the subject of this review. The various strategies for synthetic polymers are also discussed. The recent advancements in polymer production allow for more precise control, and make it possible to make functional celluloses with better physical qualities. For sustainability and environmental preservation, the development of cellulose green processing is the most abundant renewable substance in nature. The discovery of cellulose disintegration opens up new possibilities for sustainable techniques. Based on the review of recent scientific literature, we believe that additional chemical units of cellulose solubility should be used. This evaluation will evaluate the sustainability of biomass and processing the greenness for the long term. It appears not only crucial to dissolution, but also to the greenness of any process.

Manufactures of bio‐degradable and bio‐based polymers for bio‐materials in the pharmaceutical field

In recent years, bio‐based polymers have emerged as an alternative to petroleum‐based polymers in various industries. The bio‐based materials are made from raw materials originating from natural sources, such as starch, cellulose, chitin, or bio‐degradable synthetic polymers (i.e., polycaprolactone and polylactic acid). In spite of several desirable properties of biodegradable polymers, for example, fully renewable, non‐toxic. Some properties like melt and impact strength, thermal stability, permeability, and so forth, still do not meet the demands for end‐use applications. One way to improve the properties of biopolymers and greatly enhance their commercial potential is to incorporate nanosized reinforcement in the polymer. The access of nano‐carriers to smart polymeric and bio‐materials are limited by polymerization methods. Bio‐polymers are considered an alternative to petroleum‐based fibers. These are directly produced by organisms. Smart nanoparticles are used in different medicines and their applications are size‐dependent. Among the different techniques used for sensitivity, selectivity, and interactions among the nanoparticles. More so, different approaches were found for polymerization. Methodologies such as the preparation of nano‐gels, bio‐degradable, and bio‐polymers manufacturing in the pharmaceutical field are discussed in detail. Their applications, properties in gene delivery, smart imaging, and multivalency approach are also highlighted.

Performance of Poly(caprolactone) (PCL) as an Impact Modifier for Polystyrene (PS): Effect of Functionalized Compatibilizers with Maleic Anhydride and Glycidyl Methacrylate

In this work, the copolymers ethylene-glycidyl methacrylate (E-GMA), ethylene methyl methacrylate-glycidyl methacrylate (EMA-GMA), and styrene-(ethylene-butylene)-styrene grafted with maleic anhydride (SEBS-g-MA) were used to compatibilize polystyrene (PS)/poly(caprolactone) (PCL) blends. The blends were processed in a co-rotating twin-screw extruder and injection molded. Samples were investigated by torque rheometry, capillary rheometry, impact strength, tensile strength, heat deflection temperature (HDT), dynamic-mechanical thermal analysis (DMTA), thermogravimetry (TG), and scanning electron microscopy (SEM). Torque rheometry indicated that glycidyl methacrylate functional groups and maleic anhydride groups interact with PCL. Capillary rheometry evidenced that at shear rates lower than 10,000 s−1, the PS/PCL/SEBS-g-MA blends presented the highest apparent viscosity among the blends. Such behavior was possibly due to the good interaction between SEBS-g-MA and the PS and PCL phases. Consequently, the properties of impact strength, elongation at break, tensile strength, and elastic modulus were improved by 30%, 109%, 33.8%, and 13.7%, respectively, compared with the non-compatibilized PS/PCL system. There was a reduction in the HDT of all blends compared with neat PS, given the elastomeric characteristics of PCL and compatibilizers. The DMTA results revealed two independent peaks in the blends (one around −53 °C concerning the PCL phase and another at 107 °C related to PS), confirming their immiscibility. The PS/PCL/SEBS-g-MA blends showed higher morphological stability, confirming their good mechanical properties.

The Influence of Location along the Pseudostem on Enset Fiber Physio-Mechanical Properties: Application of Weibull Distribution Statistics

Enset bundle fibers were divided lengthwise into four sections from bottom to top and the sections’ physio-mechanical parameters were studied and compared. The four equal fiber sections from the bottom were 0–375 mm (EV-I), 375–750 mm (EV-II), 750 mm–1125 mm (EV-III), and 1125–1500 mm (EV-IV). The mass distribution, cross-sectional area, linear density, and diameter all decreased along the fiber sections from bottom to top. The CIE Lab-color values of each fiber section were also examined, and the L* value for EV-II fiber section was higher. In terms of mechanical properties, the Enset bundle fiber’s tensile strength and work of rupture were analyzed, and both increased by 25% from the lower fiber section to the second fiber section (EV-1 to EV-II) along the length before decreasing significantly at the top sections. The investigation indicated that a higher Weibull modulus and tensile strength characteristics for EV-II were recorded while a low Weibull modulus and low strength characteristics of the Enset bundle fiber section EV-IV were observed. The investigation of Weibull distribution variability in the EV-IV fiber location was also confirmed using one-way ANOVA. Overall, the present study investigates the impact of fiber position along the plant stem on the mechanical and physical properties of Enset bundle fibers which can be used as an input for the optimization of unidirectional composites.

Adsorption of copper ions in water by adipic dihydrazide-modified kapok fibers

Kapok fibers (Ceiba pentandra) were modified for the removal of copper ions from aqueous solutions through adsorption. In this fast and facile method, the polysaccharide-like groups of kapok were oxidized with potassium periodate. The novel modification is the loading of the fibers with adipic dihydrazide (ADH) which contain nitrogen and oxygen atoms for heavy metal ion binding. Adsorption experiments have been carried out and analyzed via atom absorption spectroscopy and ultraviolet/visible spectroscopy. In preliminary adsorption experiments, different kapok-based materials have been analyzed on their adsorption capacity and removal efficiency via atom absorption spectroscopy. ADH-modified fibers showed the best results and an increase of copper removal efficiency by 30% in comparison to untreated kapok fibers and superior adsorption capacity compared to kapok fibers loaded with oxalic dihydrazide (ODH). Moreover, the impact of initial concentration and contact time on the adsorption capacity and on the removal efficiency values of the ADH-modified kapok fibers has been studied. Another comparison of the ADH-modified fibers with raw kapok which was cleaned with Milli-Q water, dichloromethane and ethylene glycol showed that the new adsorbents are best suited for copper solutions with concentration values of under 10 mg/L. The heavy metal adsorption experiments were analyzed through both isotherm models Langmuir and Freundlich. The Langmuir model is found to be a suitable model for copper ions. The value of the maximum adsorption capacity is 4.120 mg/g. The ADH-modified kapok fibers were characterized with attenuated total reflection infrared (ATR-IR) spectroscopy, magic-angle spinning nuclear magnetic resonance (MAS-NMR) spectroscopy and scanning electron microscopy (SEM).

Modification of Cellulose Nanocrystals With 2-Carboxyethyl Acrylate in the Presence of Epoxy Resin for Enhancing its Adhesive Properties

Cellulose nanocrystals (CNCs) have unparalleled advantages in the preparation of nanocomposites for various applications. However, a major challenge associated with CNCs in nanocomposite preparation is the lack of compatibility with hydrophobic polymers. The hydrophobic modification of CNCs has attracted increasing interest in the modern era standing with long challenges and being environmentally friendly. Here, we synthesized CNCs by using cotton as raw material and then modified them with 2-carboxyethyl acrylate to improve their corresponding mechanical, adhesive, contact angle, and thermal properties. Different concentrations (1-5 wt%) of CNCs were used as modifiers to improve the interfacial adhesion between the reinforced CNCs and E-51 (Bisphenol A diglycidyl ether) epoxy resin system. CNCs offered a better modulus of elasticity, a lower coefficient of energy, and thermal expansion. Compared with the standard sample, the modified CNCs (MCNCs) showed high shear stress, high toughness, efficient degradation, thermal stability, and recycling due to the combined effect of the hyperbranched topological structure of epoxy with good compatibility. The native CNCs lost their hydrophilicity after modification with epoxy, and MCNCs showed good hydrophobic behavior (CA = 105 ± 2°). The findings of this study indicate that modification of CNCs with 2-carboxyethyl acrylate in the presence of epoxy resin and the enhancement of the features would further expand their applications to different sectors.

Effect of Potassium Phosphate Content in Aluminosilicate Matrix on Mechanical Properties of Carbon Prepreg Composites

Six matrices based on alkali-activated aluminosilicate with different amounts of potassium phosphate were prepared for the production of six-layer composite plates. The addition of potassium phosphate in the matrix was 2 wt%, 4 wt%, 6 wt%, 8 wt% and 10 wt% of its total weight. The matrix without the potassium phosphate was also prepared. The aim of this study was to determine whether this addition has an effect on the tensile strength or Young's modulus of composites at temperatures up to 800 °C. Changes in the thickness and weight of the samples after this temperature were also monitored. Carbon plain weave fabric was chosen for the preparation of the composites. The results show that under normal conditions, the addition of potassium phosphate has no significant effect on the mechanical properties; the highest measured tensile strengths were around 350 MPa. However, at temperatures of 600 °C and 800 °C the addition of potassium phosphate had a positive effect, with the tensile strength of the composites being up to 300% higher than the composites without the addition. The highest measured values of composites after one hour at 600 °C were higher than 100 MPa and after 1 h at 800 °C higher than 85 MPa.

Inorganic salt hydrates and zeolites composites studies for thermochemical heat storage

Salt hydrates (MgSO4 and ZnSO4) impregnated in zeolites, offer a variety of improvements, mostly providing a large surface area for salt hydrates and water molecules. A composite of 5 and 10% of salt contents were prepared as heat storage materials. The study’s finding showed that dehydration enthalpy of MgSO4 (1817 J g−1) and ZnSO4 (1586 J g−1) were 10 and 15% improved than pure salt hydrates by making composites. During the hydration process of composites, the water sorption is 30–37% improved and further the increasing of salt contents in composites enhances more 10% increase in the water resorption. The cyclicability of MgSO4/zeolite and ZnSO4/zeolite were 45 and 51% improved than their corresponding pure salt hydrates. The effect of humidity on the water sorption result reveals that composites of MgSO4/zeolite and ZnSO4/zeolite at 75% relative humidity (RH), the mass of water are 51 and 40% increase than 55% RH.

Synthesis and modification of silica‐based epoxy nanocomposites with different sol–gel process enhanced thermal and mechanical properties

This research article describes the results of nano‐silica composites filled with different epoxy contents containing nano‐SiO2 particles from (5–25 wt%). Reinforcing hybrid composites enhance thermal and mechanical properties to achieve vital and sustainable products. Silica‐based nanocomposites with high purity were prepared and used for the surface modification of nanosized silica particles. The surface structure's composition and physical properties of modified nano‐SiO2 particles were characterized through Fourier transferred infrared spectrometer, X‐ray photoelectron spectroscopy, thermogravimetric analyzer, and scanning electron microscopic. Silica‐based nanocomposites were prepared by incorporating of modified nano‐SiO2 as an enhancing filler. The morphology of fracture surface and dynamic mechanical properties were investigated. Results showed that the silica‐based epoxy nanocomposites are bearing a long chain structure that could improve the compatibility of silica nanocomposites with epoxy resin and contribute to a better dispersion state in the matrix, which enhanced the overall performance of epoxy‐cured products.