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Epoxy resins as important organic matrices, thanks to their chemical structure and the possibility of modification, have unique properties, which contribute to the fact that these materials have been used in many composite industries for many years. Epoxy resins are repeatedly used in exacting applications due to their exquisite mechanical properties, thermal stability, scratch resistance, and chemical resistance. Moreover, epoxy materials also have really strong resistance to solvents, chemical attacks, and climatic aging. The presented features confirm the fact that there is a constant interest of scientists in the modification of resins and understanding its mechanisms, as well as in the development of these materials to obtain systems with the required properties. Most of the recent studies in the literature are focused on green fillers such as post-agricultural waste powder (cashew nuts powder, coconut shell powder, rice husks, date seed), grass fiber (bamboo fibers), bast/leaf fiber (hemp fibers, banana bark fibers, pineapple leaf), and other natural fibers (waste tea fibers, palm ash) as reinforcement for epoxy resins rather than traditional non-biodegradable fillers due to their sustainability, low cost, wide availability, and the use of waste, which is environmentally friendly. Furthermore, the advantages of natural fillers over traditional fillers are acceptable specific strength and modulus, lightweight, and good biodegradability, which is very desirable nowadays. Therefore, the development and progress of “green products” based on epoxy resin and natural fillers as reinforcements have been increasing. Many uses of natural plant-derived fillers include many plant wastes, such as banana bark, coconut shell, and waste peanut shell, can be found in the literature. Partially biodegradable polymers obtained by using natural fillers and epoxy polymers can successfully reduce the undesirable epoxy and synthetic fiber waste. Additionally, partially biopolymers based on epoxy resins, which will be presented in the paper, are more useful than commercial polymers due to the low cost and improved good thermomechanical properties.

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In this work, a method for producing highly reactive catalysed coke from medium and non-coking coal using low-grade iron ore fines as a catalyst through two different alternate routes, namely carbonisation in a stamp charge coke oven and carbonisation in a horizontal tube furnace was attempted. Phenolic resin and petroleum pitch were individually experimented as a binding material to get adequate strength. Effect of process parameters such as coal-to-iron ratio, briquetting load, binder quantity and coking to non-coking coal ratio on the coke properties such as reactivity and mechanical strength was investigated. The SEM and petrography analysis of catalysed coke were used to study the microstructure and its effects on reactivity.

Mimosa pudica Linn (sensitive plant) is a medicinal plant of family Fabaceae. Its stem is a good source of cellulose. This research work reports isolation of cellulose nanocrystals (CNCs) from M. pudica stem fibres by combined chemical and mechanical treatments. Polyvinyl alcohol (PVA)/starch composites were prepared with incorporation of isolated CNC (1, 3 and 5 wt.%) by solution casting method. Addition of CNC in polymer composites improved its mechanical strength and barrier properties. Isolation process of CNC includes alkali treatment, bleaching and acid hydrolysis followed by homogenization. Chemical composition, thermal stability, structure, surface morphology, crystallinity and size of the freeze‐dried nanocellulose were studied carefully. Fourier transform infrared analysis of raw fibre and CNC showed elimination of non‐cellulosic fragments from untreated M. pudica stem fibre. Electron microscopy analysis and dynamic light scattering (DLS) confirmed the isolation of nanocellulose. X‐ray diffraction showed improvement in the crystallinity of obtained nanocellulose. Increase in crystallinity indicates high Young's modulus of isolated nanocellulose which makes them proper reinforcement material in composites. Polymer composites with the addition of 3 wt.% of CNC showed the highest tensile strength and lowest water vapour transmission rate (WVTR), moisture absorption and oxygen transmission rate (OTR). As M. pudica is an abundant natural resource, it can be utilized as an efficient source of nanocellulose for different applications especially as fillers in sustainable polymer composites for packaging.

Cellulose nanofibers (CNF) were isolated from raw cotton fibers via 2, 2, 6, 6-tetramethylpiperidine-1-oxyl (TEMPO) oxidation process. The isolated CNF were morphologically characterized using Field Emission Scanning Electron Microscopy (FESEM) and Transmission Electron Microscopy (TEM). Entangled fibrous morphology with diameter in nano regime (15–20 nm) has been observed for the isolated nanofibers. X-ray diffraction (XRD) analysis confirms the high crystallinity of the isolated CNF. Further, the isolated CNF was used to reinforce natural rubber (NR) latex films. The crystallographic, morphological, and spectroscopic analysis of the NR/CNF nanocomposites was carried out. A strong interaction between the CNF and NR matrix has been identified and which reflects in the thermal stability and swelling behavior of NR/CNF nanocomposite films in toluene. The uniform dispersion and tangling effect of CNF along with strong NR-CNF interaction restrict the uptake of solvent through NR matrix.

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