Heat-resistant Membrane Research Articles

High strength, thermostable and fast-drying hybrid transparent membranes with POSS nanoparticles aligned on aramid nanofibers

Hybrid organic/inorganic nanocomposites based on aramid nanofibers (ANFs) and different amounts of polyhedral oligomeric silsesquioxane (POSS) nanostructured chemicals were prepared via solution blending and vacuum-assisted flocculation, compared with traditional film fabrication methods, this process is time-saving by adopting ethanol as agglomerator. The mechanical properties of ANFPs membranes could be altered by changing the POSS content, in which the POSS served as a cross-linking agent between nanofibers, and ANFPs composite membrane presented the optimal tensile strength with 6 wt.% POSS NPs embedding in the nanocomposite. In addition to the satisfactory mechanical performance and vitreousness, the unique thermal assets of ANFs and POSS further enabled the membranes with high thermal stability. Based on these results, it could be concluded that the ANFPs membranes developed here might provide the alternative materials for the practical application of strong, transparent and heat-resistant membrane.

Strong, transparent and flexible aramid nanofiber/POSS hybrid organic/inorganic nanocomposite membranes

Mechanical performance, transparency and thermal stability still remain the dominating constraints for the application of polymeric composite membranes. Thus, the research and development of co-effectively strong, transparent and heat-resistant membranes are necessary and significant for promoting practical outcomes. POSS NPs is incorporate into the structure of aramid nanofibers (ANFs) to synthesize the ANFPs nanocomposite membranes with different amounts of POSS by vacuum-assisted flocculation. FT-IR and XPS were applied to characterize the structure of composite membranes. Upon the addition of POSS, the surface topological structures of composite membranes were not affected, and they retained excellent transparency and flexibility. The mechanical properties of ANFPs membranes could be altered by changing the POSS content, in which the POSS served as a cross-linking agent between nanofibers, and ANFPs composite membrane presented the optimal tensile strength with 6 wt% POSS embedding in the nanocomposite. Besides the excellent mechanical performance and transparency, the unique thermal assets of ANFs and POSS further enabled the membranes with high thermal stability. Based on these results, it could be concluded that the ANFPs membranes developed here might provide the alternative materials for the practical application of strong, transparent and heat-resistant membrane.

4011 柔構造エアロシェル型再突入機の実現に向けた耐熱膜面材料の開発試験(S67-1 大気突入・減速技術(1),21世紀地球環境革命の機械工学:人・マイクロナノ・エネルギー・環境)

The development of the airtight and heat-resistant membrane is an important factor to realize the low ballistic coefficient reentry spacecraft with flexible aeroshell. The air tightness is necessary for the inflatable structure and the heat-resistance against aerodynamic heating is also demanded. The candidate of the membrane is Zylon[○!R] (Toyobo. Co. Ltd.) and it can endure more than 600 degree Celsius. Authors tried to give Zylon airtight property with coating on it, but the coated sample was not airtight. If polyethylene is used as an inside layer of Zylon, the two layers system have the airtight property. As outer layer should be a heat shield in this case, radiative heat transmission test of membrane is also tested. Thicker Zylon and Zyron with Kapton[○!R] film show less transmission rate than Zylon.

Ultrapure Dialysate for Home Hemodialysis?

Use of ultrapure dialysate (bacteria < 0.1 CFU/mL and endotoxin < 0.03 EU/mL) is associated with a reduction in inflammation and morbidity in patients treated with conventional thrice-weekly dialysis. The improved outcomes obtained with more frequent dialysis schedules have reawakened interest in home hemodialysis. More frequent dialysis also appears to reduce inflammation, and whether combining more frequent dialysis with use of ultrapure dialysate will have an additive effect on inflammation and its consequences remains unclear. Routinely producing ultrapure dialysate in a home environment with a conventional hemodialysis machine poses technical challenges related to the design of the equipment and the intermittent nature of hemodialysis. Solutions to these problems include use of a system in which the water-treatment equipment is fully integrated with the dialysis machine, use of dry-powder cartridges or sterile prepackaged liquids for bicarbonate concentrate, and use of a bacteria-retentive and endotoxin-retentive filter for final purification of the dialysate immediately before it enters the dialyzer. Alternatively, ultrapure dialysate may be achieved with newer machines designed specifically for home hemodialysis that use a new batch of dialysate for each treatment. The volume of dialysate available with these machines, however, currently limits their use to short-daily dialysis.

Synthesis of cellular inorganic films from self‐organized Media

Cellular and honeycomb structures of inorganic materials are of interest for applications requiring, e.g., catalyst supports or heat‐resistant membranes. The synthesis fo cellular films from solvent‐extracted metal‐ion‐containing microemulsions (the Figure shows a resulting hollow spherical shell of calcium carbonate) is extended here to FeIII, MnIII/IV, and CoIII oxides. The preparation is detailed and the mechanism of formation discussed. magnified image