Investigation of mechanical and thermal behavior of fiber-reinforced silica xerogel composites.

Silica aerogels or xerogels are renowned dried gels with low density, high surface area, higher porosity, and better thermal stability which makes it suitable for aerospace, light weight structures, thermal insulation, and hydrophobic coatings. But brittle behaviour, low mechanical strength, and high manufacturing cost restrict its usage. Recently, the addition of various fibres like glass or carbon fiber is one of the best reinforcement methods to minimize the brittle behaviour. Supercritical drying technique usually used to develop aerogel that is expensive and difficult to produce in bulk quantities. Higher cost obstacle can be tackled by applying ambient pressure drying technique to develop xerogel. But researcher observed cracks in samples prepared through the ambient pressure drying technique is still a major shortcoming. The aim of this study is to systematically analyze the influence of silica gel fiber reinforcement on silica xerogels, encompassing morphology, mechanics, thermal behaviour, compression test, and thermogravimetric characteristics. The research used a low-cost precursor named Tetraethyl orthosilicate to synthesize low-cost composite Silica xerogel and glass and carbon fiber added to provide strength and flexibility to the overall composite. Silica gel works as binder in strengthening the xerogel network. The investigation employs scanning electron microscopy (SEM) to examine the morphology of the composites, Fourier Transform Infrared (FTIR) analysis to affirm hydrophobic characteristics, compression tests to assess mechanical strength, and thermogravimetric tests to study weight loss under different conditions. SEM results reveals that glass fibers exhibit lower adhesion to the xerogel network compared to carbon fibers. FTIR analysis confirms the hydrophobicity of the composite silica xerogel. Compression tests showed that, under a 48% strain rate, the carbon fiber composite demonstrates superior compressive stress endurance. Thermogravimetric tests revealed a 1% lower weight loss for the carbon fiber composite compared to the glass fiber composite. This work concludes that glass and carbon fiber together with silica gel particles successfully facilitated in developing flexible, less costly, hydrophobic, and crack-free silica xerogel composites by APD. These advancements have the potential to drive innovations in material science and technology across diverse industries.

Scanning electron microscopy leads to identification of novel nonedible oil seeds as energy crops.

Currently, exploration of alternative energy resources is hotly debated among the scientific community owing to rising energy crises and environmental issues. Biodiesel, as renewable energy source proves to be a better option and substitute to petro diesel. In this regard, nonedible seeds could be a better feedstock for synthesizing biodiesel due to their cost effectiveness and environmental friendly attributes. The present study, therefore, deals with the exploration and identification of micromorphologic features among eight novel nonedible oil yielding seeds via scanning electron microscopy (SEM) as potential feedstock for biodiesel industry. Light microscopic studies revealed that seeds size vary from 0.1-2.9 cm in length to 0.1-3 cm in width. Moreover, a great variation in seed color from black, green, and different shades of brown was also observed. Seeds ultra-structure examination by SEM exhibit great variation in seed shape, size, color, sculpturing and periclinal wall shape and arrangement and so on. All the understudy seeds vary from rounded, irregular, subspherical, ellipsoidal, reniform, flattened, polygonal, ovate, pyriform, oblong, and globose shape. Seeds wall structure exhibits great variation from entire, angular, straight, irregular, polygonal, smooth, and elongated. The periclinal wall pattern exhibits variation from flat to slightly concave-convex with straight, angular, undulate, or dentate seeds margin. Among the studied species only Argemone ochroleuca Linn. (Papaveraceae) possess micropylar peak, ridged raphe, and basal helium. The obtained results from the present study would therefore, suggest that SEM could be a useful tool in refreshing the veiled micromorphological features among different oil yielding seeds which in turn helps the researchers for their correct identification, exploration, authentication, and seeds classification in future.