Electrospun fiber mat

Figure 12.7 Photographs of electrospun fiber mats embedded with 1 (a) before and (b) after 254-nm UV irradiation (1 mW/cm ) for 3 min. (c) Scanning electron microscopy image of the microfibers containing polymerized 1. (c) Photographs of the polydiacetylene-embedded electrospun fiber mats prepared with various diacetylene monomers after exposure to organic solvent. Reprinted fi om Yoon et al. (2007). Copyright 2007 American Chemical Society. (See color insert.)...

PW. Gibson, HE. Schreuder-Gibson, D. Riven. 1999.Electrospun fiber mats transport properties. AIChE J., 45(l).pp. 190-195. 

Kenawy et al. [114] used electrospun fiber mats prepared either from PLA, poly (ethylene-co-vinyl acetate) (PEVA), or from a 50 50 blend of the two as carriers to... 

Dietzel et al. produced electrospun fiber mats with specific surface chemistry from random copolymers of PMMA-r-TAN. They have demonstrated that the atomic concentration of fluorine at the surface of electrospun fibers was twice the amount seen in bulk materials (Dietzel et al. 2001). The fiber diameter was in the range of 2 pm to 300 nm. 

Kenawy et al. studied the potential of electrospun fiber mats as drug delivery system for the release of tetracycline hydrochloride (Kenawy et al. 2002). Electrospun PEVA + PLA blended fibers were 1—3 pm in diameter while the PLA fibers were around 3-6 pm. Srinivasan and Reneker 1995 examined the crystal structure and morphology of the electrospun Kevlar fibers (Srinivasan and Reneker 1995). Fibers from 40 nm to a few hundreds of nanometers were produced. 

Electrospinning of PHA is still relatively new in scaffold fabrication. To date, P(3HB) and P(3HB-co-3HV) are the most common microbial polyesters to be electrospun into tissue-engineering scaffolds. Suwantong et al. (2007) prepared ultrafine electrospun fiber mats of P(3HB) and P(3HB-co-3HV) as scaffolding materials for skin and nerve generation, hi their study, they evaluated the in vitro biocompatibility of these fibers using mouse fibroblasts and Schwann cells... 

Gibson, R, Gibson, H. S., and Rivin, D. Electrospun Fiber Mats Transport Properties. AIChE Journal, 45(1), 190-195 (1999). 

Response Surfaces for Contact Angle (Ca) of Electrospun Fiber Mat 163... 

FIGURE 7 The predicted versus actual plot for AFD of electrospun fiber mat... 

Figure 10(a), (b), and (c) show the effect of solution concentration on CA of electrospun fiber mat. In this work, the CA of electrospun fiber mat decrease with increasing the solution concentration. 

The snrface plot in Figure 10(c), (e), and (f) represented the effect of volume flow rate on CA of electrospun fiber mat. Figure 10(c) shows the interaction between volume flow rate and solution concentration. As illustrated in Figure 10(e) and (f), the effect of volnme flow rate on CA of electrospun fiber mat was independent from applied voltage and spinning distance. 

The optimal conditions were established by desirability. Independent variables namely solution concentration, applied voltage, spinning distance, and volume flow rate were set in range and dependent variable (contact angle), was fixed at minimum. The optimal conditions in the tested range for minimum CAof electrospun fiber mat are shown in Table 5. 

TABLE 5 Optimum values of the process parameters for minimum CA of electrospun fiber mat. 

Conducting electrospun fiber mats based on PLA and PANI blends were reported by Picciani et al. It was observed that the resistivity values decreased with increasing PANI content and increased with increasing fiber diameter. The contact probability among fibers and the formation of the conductive pathways through the sample were introduced as a reason for that result. Thicker fibers had less contact probability in the same mat volume and an increase in fiber... 

Gibson, P.W., H.L. Schreuder-Gibson, and D. Rivin. 1999. Electrospun fiber mats Transport... 

The electrospun fiber mats possess a high surface area per unit mass, low bulk density, and high mechanical flexibihty. These features make these materials very attractive for a wide range of potential applications, as mentioned above. Among them, the use of electrospun polymer fibers for electronic applications is of particular interest. The high surface-to-volume ratio associated with electrospun conducting polymer fibers makes them excellent candidates for electrode materials since the rate of electrochemical reaction is proportional to the surface area of an electrode and diffusion rate of the electrolyte. 

Mass loss of TCH-loaded electrospun fiber mats using chloroform/methanol the fiber degradation. 

The striking structural similarity between an electrospun fiber mat such as the one shown in Fig. 2b and those water-repellent leaves shown in Fig. 1 suggests that an electrospun fiber mat has the intrinsic surface roughness required for superhy-drophobicity. As described in the several examples below, this is indeed the case. 

Figure 3. Water droplets on PS-PDMS/PS electrospun fiber mat. (Reproduced with permission from [21]. Copjnight American Chemical Society, 2005.)...

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