Nanofiber polyamide

Synthetic nanofiber matrices can provide physically and chemically stable 3D surfaces for ex vivo growth of cells. Meiners and coworkers showed that fibroblasts or rat kidney cells that have been grown on electrospun polyamide nanofiber meshes displayed all the characteristics of their counterparts in vivo [205], In addition, breast epithelial cells underwent morphogenesis to form multicellular spheroids containing lumens. 

F. Granato, A. Bianco, C. Bertarelli, and G. Zerbi, Composite polyamide 6/polypyrrole conductive nanofibers, Macromolec. Rapid Commun., 30, 453 58 (2009). 

Some authors have proposed several modified process approaches to obtain electroactive electrospun nanofibers. One first practical and easy way is to spin a nonconductive polymeric web and after polymerize conductive polymers onto the fiber surface. For example, conductive polyamide-6 (PA-6] nanofibers were prepared by polymerizing pyrrole (Py] molecules directly on the fiber surface of PA-6. First, a solution of PA-6 added with ferric chloride in formic acid was electrospun with average diameter values around 260 nm. 

Nanofibers of polyamide 6 (PA6) with different contents of poly (aniline) (PANI) doped with p-toluene sulfonic acid (TSA) were obtained by blending method. ... 

Granato E, Bianco A, Bertarelli C., and Zerbi G., Composite polyamide 6/poiypyrrole conductive nanofibers, MacromoL Rapid Commun., 2009,30,453-458. 

A thin layer of pol5mier solution covers the rotating electrode, and multiple jets are formed due to the action of the electrical field. The Elmarco company offers a wide assortment of spim-bonded nonwovens covered by nanofiber membranes made of polyamide, pol5mrethane and... 

Scientists investigated the electrochemical catalytical properties based on Pd/polyamide (Pd/PA6) electrospun nanofiber mats for the oxidation of ethanol in alkaline medium in which Pd/PA6 was directly used as electro-catalytic electrodes. 

Figure 5.8 An AFM image of an electrospun polyamide nanofiber. Reprinted with permission from Q. F. Wei et al. (2006). Copyright 2006. John Wiley Sons.

L. Su, W. Jia, A. Schempf, Y. Ding, Free-standing paUadium/polyamide 6 nanofibers for electrooxidation of alcohols in alkaline medium, Y. Lei, J. Phys. Chem. C113 (2009) 16174-16180. 

Demirel, A.L., Meyer, M., and Schlaad, H. (2007) Formation of polyamide nanofibers by directional crystallization in aqueous solution. Angewandte Chemie International Edition, 46,8622-8624. 

A thin layer of polymer solution covers the rotating electrode, and multiple jets are formed due to the action of the electrical field. The Elmarco company offers a wide assortment of spun-bonded nonwovens covered by nanofiber membranes made of polyamide, polyurethane and polyvinyl alcohol. A further approach related to spinning directly from the solution surface was invented by Yarin and Zussman [12]. The proposed system is composed from two layers a bottom layer in the form of ferromagnetic suspension and an upper layer in the form of pol5mier solution. The two- layer system is subjected to the magnetic field provided by a permanent magnet. The scheme of this apparatus is presented in Figure 3.3. 

In comparison with other nanomaterials, electrospun nanofibers are featured with good continuity, extremely large length-to-diameter ratio, high surface-area-to-volume ratio, and ease of surface functionalization. Meanwhile, multiple extra functions can be incorporated into electrospun nanofibers fo broaden their significances in applications. Because of this, we have found in the open literature that more than 50 polymers have been successfully fabricated into sensors, involving polyamide-6 (PA-6), polyamide-6,6 (PA-6,6), polyacrylonitrile (PAN), polyurethane (PU), poly(acrylic acid) (PAA), Ti02, ZnO, cellulose acetate (CA), polyethylene oxide (PEO), polystyrene (PS), poly(vinylidene fluoride) (PVdF), etc. (Fig. 11.1). 

Guibo Y, Qing Z, Yahong Z, Yin Y, Yumin Y (2013) The electrospun polyamide 6 nanofiber membranes used as high efficiency filter materials filtration potential, thermal treatment, and their continuous production. J Appl Polym Sci 128(2) 1061-1069. doi 10.1002/app.38211... 

In addition to HAp/polymer composite nanofibers, examples of hybrid fibers produced by electrospinning inorganic nanoparticles include boehmite in polyamide 6 [84] and calcium carbonate nanoparticles in poly(e-caprolactone) [85]. 

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