Bundle sheath polymers

To solve the problem of poor adhesion between fiber mats and the substrate, Kim et al. (2006) introduced an additional hot-pressing step after titania fiber deposition. Besides improving adhesion, this treatment was found to have an impact on the microstracture of the fibers as shown in Fig. 2.11. The as-spun metal oxide-polymer composite fibers exhibit a range of diameters from 200 to 500 nm (Fig. 2.11a). When calcined without hot-pressing to remove the organic vehicle, a bundle structure composed of sheaths of 200-500 mn diameters was obtained. In some cases, the outer sheaths were broken, revealing cores filled with 10-nm-thick fibrils as shown in Fig. 2.11c. By introducing the... 

Also, the electrospun fibres can be deposited either randomly to form a nonwoven web or in an oriented manner to give an aligned nanofibre array. Twisting nanofibre bundles can form nanofibre yarns. Within the fibre web, the nanofibres can be connected physically or bonded at cross-points to form an interconnected spider web . In addition, two polymer components have been combined to form side-by-side, or sheath-core, bicomponent electrospun fibres. 

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