Polysulfone, nanofiber

Li G, Li P, Yu Y, Jia X, Zhang S, Yang X, Rjni S (2008) Novel carbon fiber/epoxy composite toughened by electrospun polysulfone nanofibers, Mater Lett 62 511-514. 

Z. Fan, Z. Wang, N. Sun, J. Wang, and S. Wang, Performance improvement of polysulfone ultrafiltration membrane by blending with polyaniline nanofibers, J. Membrane Set, 320, 363-371 (2008). 

The cellulose based materials that are used as nano-reinforcements are cellulose nanocrystals (i.e. whiskers and nanospheres), nanofibrillated cellulose, regenerated cellulose nanoparticles and electrospun nanofibers. A wide range of polymer matrices have been used to form cellulose nanocomposites. Synthetic polymers such as polypropylene, poly(vinyl chloride) (PVC) [102], waterborne epoxy [103], waterborne polyurethane [104], polyurethane [105], poly-(styrene-co-butyl acrylate) [106], poly(oxyethylene) [107], polysiloxanes [108], polysulfonates [109], cellulose acetate butyrate [110,111], poly(caprolactone) [112], poly(viny 1 alcohol) [113] and poly (vinyl acetate) [114]. Different biopolymers such as starch-based... 

Two types of poly electrolyte nanofiber mats were prepared in this study. One was polyacrylic acid (Mv = 450,000) fibers, spun from 5 wt% of aqueous solution. The other one was polysulfone fibers, spun from 25 wt% of DMF solution. The polysulfone fiber was then coated with a layer of polyelectrolyte, FAMPS, by a surface grafting technique (FAMFS-g-FS) similar to the procedure described previously. Nucrel membranes wereprepared by heat pressing Nucrel 535 (DuPont) pellets at 125°C. For fiber encapsulation, the fiber mats with measured weight and thickness were placed between two preweighed Nucrel membranes and then pressed at 125°C. The resulting composite membranes were flexible and robust with a homogeneous transparency. 

Figure 5. SEM image of (a) Nucref membrane (bl) PAA electrospun nanofiber mat (b2-bS) PAA nanofiber encapsulated Nucref membrane (cl) polysulfone (PS) electrospun nanofiber mat (c2) PAMPS-g-PS electrospun nanofiber mat (c3) PS nanofiber encapsulated Nucref membrane (c4) PAMPS-g-PS nanofiber encapsulated Nucref membrane.

Wang et al. (2006) immobilized the lipase enzyme from Candida rugosa by physical adsorption on the surface of polysulfone (PSF) composite nanofibrous membranes. PVP and PEG were used as additives, aiming to tailor the surface properties of the PS nanofibers, increasing their hydrophilicity. The results showed that the activity of the immobilized lipase increased with the content of PVP or PEG, whereas the adsorbed amount of lipase was unchanged. These results were attributed to the enrichment of PVP or PEG at the nanofiber surface. In another study, lipase from Pseudomonas cepacia was immobilized by physical adsorption onto electrospun PAN fibers and used for the conversion of (S)-glycidol with vinyl n-butyrate to glycidyl n-butyrate in isooctane (Sakai et al. 2010). 

Choi J, Lee KM, Wycisk R, Pintauro PN, Mather PT (2010) Sulfonated polysulfone/POSS nanofiber composite membranes for PEM fuel cells. J Electrochem Soc 157(6) B914-B919... 

More than 100 polymers, both synthetic and natural, have been successfully electrospun into nanofibers, mostly from polyma solutions, as any polymer may be electrospun into nanofibers, provided that the polymer molecular weight is sufficiently high and the solvent can be evaporated in the time during the jet transit period, over a distance between the spinneret and the collector. Standard polymers successfully electrospun into nanofibers include polyacrylonitrile (PAN), poly(ethylene oxide) (PEO), poly(ethylene terephthalate) (PET), polystyrene (PS), poly(vinyl chloride) (PVC), Nylon 6, PVA, poly(8-caprolactone), Kevlar (poly[p-phenylene terephthalamide]), poly(vinylidene fluoride) (PVDF), polybenzimidazole, polyurethanes (PUs), polycarbonates, polysulfones, poly(vinyl phenol) (PVP), and many others [36,37]. Electrospinning has also been used to produce nanofibers from natural biomacromolecules, including cellulose [either electrospun from cellulose acetate (CA) with subsequent hydrolysis or directly electrospun from cellulose solutions in Af,Af-dimethylacetamide with lithium chloride], collagen and gelatin, modified chitin, chitosan, and DNA. 

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