Three types of polyimide membranes viz., Matrimid, Kapton and P84, were prepared by solution casting and solvent evaporation method to study the permeation of CO 2 and CH 4 gases. Barrier properties were investigated as a function of feed pressure for pure gases and feed composition for the binary mixtures of CO 2 and CH 4 . Kapton polyimide, prepared by imidization of polyamic acid, showed an increase in permeability, but reduction in selectivity, due to the occurrence of plasticization at higher feed CO 2 concentrations. Matrimid was found to exhibit the highest permeability and was studied in greater detail, due to the feasibility in its scale-up into a hollow fiber modular configuration for commercial application. Matrimid was characterized by Fourier transform infrared (FTIR) spectroscopy and X-ray diffractometry (XRD) to assess the intermolecular interactions and to understand the separation profiles. The effect of feed flow was evaluated by studying the permeation behavior of flat sheet membrane in dead-end operation mode with the hollow fiber module operated in crossflow feed mode. For pure gases, Matrimid hollow fiber membrane exhibited a CO 2 permeability of 12.7 Barrers with a CO 2 /CH 4 selectivity of 40 at the feed pressure of 20 bar. At the same pressure, for binary mixture feed of 5 mol % CO 2 in methane, the module gave a permeability of 7.4 Barrers with a selectivity of 21. The total binary mixture permeability was determined at the feed CO 2 concentrations varying from 0 to 20 mol % to demonstrate the preferential sorption of CO 2 in Matrimid membrane.

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Nanocomposite membranes of poly(vinyl alcohol)-polyaniline (PANI)-coated titanium dioxide (PVA-PANI-TiO 2 ), as well as TiO 2 , cross-linked with glutaraldehyde were tested for their suitability in dehydrating aqueous mixtures of 1,4-dioxane or tetrahydrofuran (THF) by pervaporation (PV). The effect of feed composition and filler loading on PV separation performance was examined. Sorption studies were performed in feed mixtures to assess the extent of interaction between membranes and feed components. The addition of a small amount of nano-sized filler particles into a cross-linked PVA membrane was responsible for an increase in membrane selectivity to water. Among the cross-linked nanocomposite PVA membranes, TiO 2 coated with 0.5 wt% PANI gave higher sorption than other membranes. Sorption of the cross-linked (unfilled) PVA membranes was higher compared to all the nanocomposite membranes. Addition of filler particles reduced the extent of sorption with improved membrane performance.

Composite membranes of sodium alginate prepared by incorporating nanosized-activated charcoal particles were prepared and characterized for the extent of cross-linking, thermal stability, and mechanical strength properties using Fourier transform infrared, differential scanning calorimetry, and universal testing machine, respectively. The membranes were tested for pervaporation (PV) dehydration of isopropanol (IPA), ethanol (EtOH), 1,4-dioxane (1,4-D), and tetrahydrofuran (THF) at their azeotropic compositions. Improved PV performances of the composite membranes were observed compared with plain sodium alginate membrane for all the azeotropes. Sorption was studied to evaluate the extent of interactions between liquids and membranes as well as

ABSTRACT:Interpenetrating polymeric network (IPN) membranes of sodium alginate (NaAlg) and various amounts of poly(hydroxyethylmethacrylate) (PHEMA) have been prepared and tested for the pervaporation dehydration of ethanol and tetrahydrofuran (THF). The presence of hydrophilic PHEMA in the IPN matrix was found to be responsible for increase in membrane selectivity to water. NaAlg-PHEMA IPN membrane containing 20 wt % of PHEMA exhibited a selectivity of 571 to water for the waterethanol mixture and 857 for water-THF mixture. These data are much better than those observed for the pristine NaAlg membrane. However, flux of the IPN membranes was smaller than that of pristine NaAlg membrane. Comparatively higher flux values were observed for water-THF mixture than for water-ethanol mixture.

Whether it is a plant- or animal-based bio-inspiration design, it has always been able to address one or more product/component optimisation issues. Today’s scientists or engineers look to nature for an optimal, economically viable, long-term solution. Similarly, a proposal is made in this current work to use seven different bio-inspired structures for automotive impact resistance. All seven of these structures are derived from plant and animal species and are intended to be tested for compressive loading to achieve load-bearing capacity. The work may even cater to optimisation techniques to solve the real-time problem using algorithm-based generative shape designs built using CATIA V6 in unit dimension. The samples were optimised with Rhino 7 software and then simulated with ANSYS workbench. To carry out the comparative study, an experimental work of bioprinting in fused deposition modelling (3D printing) was carried out. The goal is to compare the results across all formats and choose the best-performing concept. The results were obtained for compressive load, flexural load, and fatigue load conditions, particularly the number of life cycles, safety factor, damage tolerance, and bi-axiality indicator. When compared to previous research, the results are in good agreement. Because of their multifunctional properties combining soft and high stiffness and lightweight properties of novel materials, novel materials have many potential applications in the medical, aerospace, and automotive sectors.