Flax is a commercial crop grown in many parts of the world both for its seeds and for its fibers. The seed-based flax variety (linseed) is considered less for its fiber after the seed is extracted. In this study, linseed straw was utilized and processed to extract fiber and cellulose through optimization of retting time and a multi-step alkaline peroxide extraction process using the Taguchi design of experiment (DOE). Effects of retting duration on fiber properties as well as effects of solvent concentration, reaction temperature, and time on removal of non-cellulosic fiber components were studied using the gravimetric technique, Fourier transform infrared (FTIR) spectroscopy and thermal studies. Based on these findings, retting for 216 h at room temperature should offer adequate retting efficiency and fiber characteristics; 70% cellulose yield was extracted successfully from linseed straw fiber using 75% ethanol–toluene at 98 °C for 4 h, 6% NaOH at 75 °C for 30 min, and 6% H₂O₂ at 90 °C for 120 min.

Scholars are looking for solutions to substitute hazardous substances in manufacturing nanocellulose from bio-sources to preserve the world’s growing environmental consciousness. During the past decade, there has been a notable increase in the use of cellulose nanocrystals (CNCs) in modern science and nanotechnology advancements because of their abundance, biocompatibility, biodegradability, renewability, and superior mechanical properties. Spherical cellulose nanocrystals (J–CNCs) were successfully synthesized from Jenfokie micro-cellulose (J–MC) via sulfuric acid hydrolysis in this study. The yield (up to 58.6%) and specific surface area (up to 99.64 m²/g) of J–CNCs were measured. A field emission gun–scanning electron microscope (FEG-SEM) was used to assess the morphology of the J–MC and J–CNC samples. The spherical shape nanoparticles with a mean nano-size of 34 nm for J–CNCs were characterized using a transmission electron microscope (TEM). X-ray diffraction (XRD) was used to determine the crystallinity index and crystallinity size of J–CNCs, up to 98.4% and 6.13 nm, respectively. The chemical composition was determined using a Fourier transform infrared (FT–IR) spectroscope. Thermal characterization of thermogravimetry analysis (TGA), derivative thermogravimetry (DTG), and differential thermal analysis (DTA) was conducted to identify the thermal stability and cellulose pyrolysis behavior of both J–MC and J–CNC samples. The thermal analysis of J–CNC indicated lower thermal stability than J–MC. It was noted that J–CNC showed higher levels of crystallinity and larger crystallite sizes than J–MC, indicating a successful digestion and an improvement of the main crystalline structure of cellulose. The X-ray diffraction spectra and TEM images were utilized to establish that the nanocrystals’ size was suitable. The novelty of this work is the synthesis of spherical nanocellulose with better properties, chosen with a rich source of cellulose from an affordable new plant (studied for the first time) by stepwise water-retted extraction, continuing from our previous study.

In this article, highly porous and transparent silicon oxycarbide (SiOC) gels are synthesized from Bis(Triethoxysilyl) methane (BTEM). The gels are synthesized by the sol-gel technique followed by both ambient pressure and supercritical drying. Then, the portion of wet gels have been pyrolyzed in a hydrogen atmosphere at 800 and 1100 °C. The FT-IR spectroscopy analysis and nitrogen sorption results indicate the successful synthesis of Si-O-Si bonds and the formation of mesopores. From a hysteresis loop, the SiOC ceramics showed the H₁ type characteristic with well-defined cylindrical pore channels for the aerogel and the H₂ type for the ambigel samples, indicating that the pores are distorted due to the capillary stress. The produced gels are mesoporous materials having high surface areas with a maximum of 1140 m²/g and pore volume of 2.522 cm³/g obtained from BTEM aerogels. The pyrolysis of BTEM aerogels at 800 °C results in the production of a bulk and transparent sample with a slightly pale white color, while BTEM xerogels are totally transparent and colorless at the same temperature. At 1100 °C, all the aerogels become opaque brown, confirming the formation of free carbon and crystalline silicon.

Epoxy polymer, an illustrious barrier corrosion protective coating, was reinforced with metakaolin clay, an eco-friendly inorganic filler to enhance the barrier corrosion protection properties in water and in acidic environment on galvanized steel plates. Various proportions 0, 1, 3, 5, and 7 wt.% of metakaolin fillers were mixed intrinsically with kadilux epoxy and characterized for thermal stability, water absorption according to ASTM G31, and acid immersion according to ASTM D-570 standards, respectively. The reinforced coatings minimized the pore size and density, lower water absorption, and better acid resistance properties especially at 7 wt.% of the fillers. The thermal stability of the films improved beyond 5 wt.% of filler composition.

Linseed straw is the stalk or stem of the linseed plant that remains after the seeds have been harvested. This agricultural waste is generated every year and is mostly left or burned in fields, causing environmental problems. This study focuses on the isolation and characterization of crystalline nanocellulose (CNC) from linseed straw fibers as a potential alternative source. The CNCs were isolated using sequential chlorine-free chemical and mechanical treatments, involving three main steps: pre-treatment, acid hydrolysis, and post-treatment. The isolated CNC was thoroughly characterized for its morphology, particle size, aspect ratio, crystallinity, crystallite size, cellulose polymorph, thermal properties, and chemical composition, compared to raw fiber (RF) and micro cellulose (MC). Characterization techniques such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FT–IR) were employed. The rod-like CNCs obtained exhibited a yield of 79.87 ± 1.35%, with a mean diameter of 7.06 ± 1.95 nm and a length of 66.14 ± 28.58 nm. The aspect ratio was measured at 10.02 ± 4.87 nm, with a crystallinity index of 73.29% and a crystallite size of 5.61 nm. Additionally, the CNCs displayed an average molecular weight of 2.36 × 10⁴ g/mol, an average degree of polymerization of 146, and a peak decomposition temperature of 515°C. These results suggest that linseed straw fibers are a promising source for the production of CNC, which can effectively serve as a filler in polymer composites.