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This study aims to investigate the behavior of the green biomass-derived copper (lignin/silica/fatty acids) complex, copper lignin/silica/fatty acids (Cu-LSF) complex, when incorporated into the nonpolar ethylene propylene diene (EPDFM) rubber matrix, focusing on its reinforcing and antioxidant effect on the resulting EPDM composites.

The structure of the prepared EPDM composites was confirmed by Fourier-transform infrared spectroscopy, and the dispersion of the additive fillers and antioxidants in the EPDM matrix was investigated using scanning electron microscopy. Also, the rheometric characteristics, mechanical properties, swelling behavior and thermal gravimetric analysis of all the prepared EPDM composites were explored as well.

Results revealed that the Cu-LSF complex dispersed well in the nonpolar EPDM rubber matrix, in thepresence of coupling system, with enhanced Cu-LSF-rubber interactions and increased cross-linking density, which reflected on the improved rheological and mechanical properties of the resulting EPDM composites. From the various investigations performed in the current study, the authors can suggest 7–11 phr is the optimal effective concentration of Cu-LSF complex loading. Interestingly, EPDM composites containing Cu-LSF complex showed better antiaging performance, thermal stability and fluid resistance, when compared with those containing the commercial antioxidants (2,2,4-trimethyl-1,2-dihydroquinoline and N-isopropyl-N’-phenyl-p-phenylenediamine). These findings are in good agreement with our previous study on polar nitrile butadiene rubber.

The current study suggests the green biomass-derived Cu-LSF complex to be a promising low-cost and environmentally safe alternative filler and antioxidant to the hazardous commercial ones.

Dehydrated bacterial cellulose’s (BC) intrinsic rigidity constrains applicability across textiles, leather, health care and other sectors. This study aims to yield a novel BC modification method using glycerol and succinic acid with catalyst and heat, applied via an industrially scalable padding method to tackle BC’s stiffness drawbacks and enhance BC properties.

Fabric-like BC is generated via mechanical dehydration and then finished by using padding method with glycerol, succinic acid, catalyst and heat. Comprehensive material characterizations, including international testing standards for stiffness, bending properties (cantilever method), tensile properties, moisture vapor transmission rate, moisture content and regain, washing, thermal gravimetric analysis, derivative thermogravimetry, Fourier-transform infrared spectroscopy and colorimetric measurement, are used.

The combination of BC/glycerol/succinic acid dramatically enhanced porous structure, elongation (27.40 ± 6.39%), flexibility (flexural rigidity of 21.46 ± 4.01 µN m; bending modulus of 97.45 ± 18.20 MPa) and moisture management (moisture vapor transmission rate of 961.07 ± 86.16 g/m²/24 h; moisture content of 27.43 ± 2.50%; and moisture regain of 37.94 ± 4.73%). This softening process modified the thermal stability of BC. Besides, this study alleviated the drawbacks for washing (five cycles) of BC and glycerol caused by the ineffective affinity between glycerol and cellulose by adding succinic acid with catalyst and heat.

The study yields an effective padding process for BC softening and a unique modified BC to contribute added value to textile and leather industries as a sustainable alternative to existing materials and a premise for future research on BC functionalization by using doable technologies in mass production as padding.

This paper aims to focus on the synthesis of the macrocyclic complexes (Cu and Zn) and their applications as anticorrosive materials in epoxy paint formulation for surface coating application.

A selected macrocyclic Cu(II) and Zn(II) complexes were prepared via template synthesis and characterized using Fourier transform infrared, thermal gravimetric analysis, scanning electron microscope, flexibility, hardness and adhesion of coating films prepared using epoxy paint.

The corrosion resistance of the epoxy-painted films was improved due to the incorporation of the Zn and Cu complexes into the formulation.

It was found that the metal complex-based formulation with Cu(II) and Zn(II) had outperformed the sample blank.

This paper aims to study a new halogen-free fame-retardant curing agent 1-aminoethylidenediphosphonate (AAEDP).

The AAEDP was synthesized by phosphoric acid, acetonitrile and ammonia. The chemical structures of AAEDP were characterized by proton nuclear magnetic resonance, mass spectrometry and Fourier transform infrared spectrometer. Thermal gravimetric analysis (TGA) and scanning electron microscope (SEM) would study the thermal properties and the char residues of AAEDP/EP. The thermal stability, mechanical and flame properties and morphology for the char layer of composite materials were separately investigated using TGA, tensile and charpy impact tests, limiting oxygen index (LOI), UL-94 HB flammability standard (UL-94) and SEM.

The results showed that the AAEDP had been prepared successfully. When the intumescent flame retardant was added into the EP, the LOI of composite material was improved.

The AAEDP can be prepared successfully and can improve the flame resistance of composite material.

The AAEDP has excellent flame-retardant properties and produce no toxic fumes when burnt in case of fire.

The results showed that the phosphorus content of AAEDP was 2.958 Wt.%; the impact and tensile strength of the composite material were 6.417 kJ m⁻² and 38.0 MPa, respectively; and the LOI and UL-94 were 29.7% and V-0 ranking, respectively. The TGA results indicated that the carbon residue ratio can be increased by 1000°C in air. The denser and more uniform structure of residual carbon prevents heat transfer and diffusion, restricts the production of combustible gas and reduces the rate of heat release.

In this paper the aim is that Aramid/alginate blended nonwoven fabrics were prepared, and the flame retardancy of the blended nonwoven fabrics was studied by thermogravimetric analysis, vertical flame test, limiting oxygen index (LOI) and cone calorimeter test.

The advantages of different fibers can be combined by blending, and the defects may be remedied. The study investigates whether incorporating alginate fibers into aramid fibers can enhance the flame retardancy and reduce the smoke production of prepared aramid/alginate blended nonwoven fabrics.

Thermogravimetric analysis indicated that alginate fibers could effectively inhibit the combustion performance of aramid fibers at a higher temperature zone, leaving more residual chars for heat isolation. And vertical flame test, LOI and cone calorimeter test testified that the incorporation of alginate fibers improved the flame retardancy and fire behaviors. When the ratio of alginate fibers for aramid/alginate blended nonwoven fabrics reached 80%, the incorporation of alginate fibers could notably decreased peak-heat release rate (54%), total heat release (THR) (29%), peak-smoke production rate (93%) and total smoke production (86%). What is more, the lower smoke production rate and lower THR of the blends vastly reduced the risk of secondary injury in fires.

This study proposes to inhibit the flue gas release of aramid fiber and enhance the flame retardant by mixing with alginate fiber, and proposes that alginate fiber can be used as a biological smoke inhibitor, as well as a flame retardant for aramid fiber.

For the sake of sustainable development and environmental preservation, it is crucial to develop UV-curable coatings composed of renewable resources. Castor oil, being both bio-based and economical, serves as the focal point of this research paper. The purpose of this research paper is to synthesize, formulate and apply a UV-curable biobased oligomer ECOSAGMA as a wood coating, with a focus on sustainable development and environmental preservation. Castor oil, being both bio-based and economical, serves as the focal point of this research paper.

ECOSAGMA was prepared by reacting epoxidized castor oil with sebacic acid, followed by reaction with glycidyl methacrylate through ring opening reaction. The chemical structure of ECOSAGMA was confirmed by Fourier-Transform infrared spectroscopy, 13C-NMR and 1H-NMR spectroscopy. The synthesized oligomer was used for UV-curable coating formulations by combining it with varying amounts of TMPTA from 10 to 40 wt.% and studied for their rheological properties. The UV curable formulations were co-photopolymerized into thin coatings and were thoroughly examined based on thermal, chemical and mechanical properties.

The UV-cured coating containing ECOSAGMA and TMPTA exhibits exceptional mechanical, chemical and thermal properties, underscoring their potential for deployment in real-world application. It is observed that an increase in the concentration of TMPTA is associated with a notable enhancement in the properties of the UV-cured coatings. The UV-cured wood coating, composed of 40 wt.% TMPTA, demonstrates remarkable stain resistance properties.

In conclusion, by embracing eco-friendly and economically conscious principles., it is evident that this synthesized novel castor oil-based oligomer offers a range of valuable properties to the coating such as stain resistance and thermal stability as well as characteristics such as gloss, hardness, adhesion and chemical resistance.

This study aims to develop multifunctional, namely, superhydrophobic, flame-retardant and antibacterial, coatings over cotton fabric, using casein as green-based flame-retardant and silver nanoparticles as antibacterial agent by solution immersion method.

The cotton fabric is first coated with casein to make it flame-retardant. AgNPs synthesized using Cinnamomum zeylanicum bark extract is coated over the casein layer. Finally, stearic acid is used to coat the cotton to make it superhydrophobic. X-ray diffraction, transmission electron microscopy analysis and ultraviolet-visible spectroscopy are used to investigate the produced AgNPs. The as-prepared multifunctional cotton is characterized by scanning electron microscopy, energy dispersive X-ray analysis and attenuated total reflection-infrared studies. Flame test, limiting oxygen index test and thermogravimetric analyzer studies have also been performed to study the flame-retardant ability and thermal stability of treated fabric, respectively. The antibacterial effect of the coatings is evaluated by disc-diffusion technique. Water contact angle is determined to confirm the superhydrophobic nature of cotton fabric.

The outcomes of this study showed that the prepared multifunctional cotton fabric had maximum contact angle of greater than 150° with good flame retardancy, high thermal stability, greater washing durability and high antibacterial activity against the growth of Pseudomonas aeruginosa and Acinetobacter indicus. Additionally, the as-prepared superhydrophobic cotton showed an excellent oil–water separation efficiency.

The trilayered multifunctional cotton fabric has limiting washing durability up to 20 washing cycles. Treated functional fabric can be used as an antibacterial, therapeutic, water repellent and experimental protective clothing for medical, health care, home curtains and industrial and laboratory purposes.

The study brings out the robustness of this method in the development of multifunctional cotton fabrics.

The type 120 emergency valve is an essential braking component of railway freight trains, but corresponding diaphragms consisting of natural rubber (NR) and chloroprene rubber (CR) exhibit insufficient aging resistance and low-temperature resistance, respectively. In order to develop type 120 emergency valve rubber diaphragms with long-life and high-performance, low-temperatureresistant CR and NR were processed.

The physical properties of the low-temperature-resistant CR and NR were tested by low-temperature stretching, dynamic mechanical analysis, differential scanning calorimetry and thermogravimetric analysis. Single-valve and single-vehicle tests of type 120 emergency valves were carried out for emergency diaphragms consisting of NR and CR.

The low-temperature-resistant CR and NR exhibited excellent physical properties. The elasticity and low-temperature resistance of NR were superior to those of CR, whereas the mechanical properties of the two rubbers were similar in the temperature range of 0 °C–150 °C. The NR and CR emergency diaphragms met the requirements of the single-valve test. In the low-temperature single-vehicle test, only the low-temperature sensitivity test of the NR emergency diaphragm met the requirements.

The innovation of this study is that it provides valuable data and experience for future development of type 120 valve rubber diaphragms.

Three-dimensional (3D) printing is popular for many applications including the production of photocatalysts. This paper aims to focus on developing of 3D-printed photocatalyst-nano composite lattice structure. Digital light processing (DLP) 3D printing of photocatalyst composites was performed using photosensitive resin mixed with 0.5% Wt. of TiO₂ powder and varying amounts (0.025% Wt. to 0.2% Wt.) of graphene nanoplatelet powder. The photocatalytic efficiency of DLP 3D-printed photocatalyst TiO₂ composite was investigated, and the effects of nano graphite powder incorporation on the photocatalytic activity, thermal and mechanical properties were investigated.

Methods involve 3D computer-aided design modeling, printing parameters and comprehensive characterization techniques such as structural equation modeling, X-ray diffraction, thermogravimetric analysis, Fourier-transform infrared (FTIR) and mechanical testing.

Results highlight successful dispersion and characteristics of TiO₂ and graphene nanoplatelet (GNP) powders, intricate designs of 3D-printed lattice structures, and the influence of GNPs on thermal behavior and mechanical properties.

The study suggests applicability in wastewater treatment and environmental remediation, showcasing the adaptability of 3 D printing in designing effective photocatalysts. Future research should focus on practical applications and the long-term durability of these 3D-printed composites.

This study aims to explore the enhancement of mechanical properties in epoxy resin composites through the incorporation of graphene nanoparticles, focusing on their impact and wear resistance. It investigates the role of graphene, both treated and untreated, as a reinforcing agent in composites, highlighting the significance of nanoparticle dispersion and surfactant treatment in optimizing mechanical performance.

Employing a novel dispersion technique using a drawing brush, this research contrasts with traditional methods by examining the effects of graphene nanoparticle concentrations treated with surfactants – Polyvinylpyrrolidone (PVP) and Sulphonated Naphthalene Formaldehyde (SNF) – on the mechanical properties of epoxy resin composites. The methodology includes conducting a series of impact and wear tests to assess the influence of graphene reinforcement on the composites' performance.

The findings reveal a marked enhancement in the composites impact resistance and energy absorption capabilities, which escalate with an increase in graphene content. Additionally, the study demonstrates a significant improvement in wear resistance, attributed to the superior mechanical properties, robust interface adhesion and effective dispersion of graphene. The use of surfactants for graphene treatment is identified as a crucial factor in these advancements, offering profound insights into the development of advanced composite materials for diverse industrial uses.

This study introduces a unique dispersion technique for graphene in epoxy composites, setting it apart from conventional methods. By focusing on the critical role of surfactant treatment in enhancing the mechanical properties of graphene-reinforced composites, it provides a novel insight into the optimization of impact and wear resistance.