• Journal of Radiation Industry
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• v.5 no.1
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• pp.69-73
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• 2011

Polyamide 66 (PA66) nanofibers with Triallyl cyanurate (TAC) were obtained by electrospinning of formic acid and chloroform solution. Electron beam irradiation of PA66 nanofiber with and without TAC was carried out over a range of absorbed doses (20~100 kGy) in nitrogen. The characterization of the irradiated PA66 nanofibers and PA66 nanofibers with TAC was done by scanning electron microscopy (SEM), nuclear magnetic resonance (NMR), thermogravimetric analysis (TGA) and universal testing machine (UTM). The results of the SEM image analysis confirmed that the morphology of PA66 nanofibers was not altered by electron beam. The amount of TAC in PA66 nanofiber with TAC was identified by $^1H-NMR$ analysis. The degradation temperature of PA66 nanofibers with TAC at an absorbed dose of 20~100 kGy was higher than the irradiated PA66 nanofiber without TAC. On the other hand, the decreasing rate of modulus of irradiated PA66 nanofibers with TAC was less than PA66 nanofibers.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.3
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• pp.124-128
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• 2011

Electrospun webs have been widely investigated for applying to drug delivery system (DDS) because of their high specific surface area and high porosity. In this study, the composite webs of PLA (poly(lactic acid)) and $TiO_2$ were fabricated by melt-electro-spinning method for applying to drug delivery system. The morphologies of PLA/$TiO_2$, webs were observed using scanning electron microscope (SEM) and field emission transmission electron microscope (FE-TEM). The crystal structures of PLA/$TiO_2$ composite webs were confirmed by X-ray diffractometer (XRD).

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.386-390
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• 2009

In this study, sulfadiazine acrylamide monomer was synthesized by the reaction of sulfadiazine, known as an antibiotic substance, with acryloyl chloride. The monomer was characterized by $^1H-NMR$, and $^{13}C-NMR$. Using the synthesized sulfadiazine acrylamide monomer and styrene monomer, a copolymer, poly(styrene-co-sulfadiazine), was obtained by the free radical copolymerization and characterized by $^1H-NMR$, GPC, DSC and TGA. The copolymer nanofibers web has been successfully prepared by electrospinning technique under DMF solution. The diameter of the nanofibers was in the range between 500 and 800 nm. Antibacterial activity of the nanofiber web was evaluated utilizing the colony counting method against Staphylococcus aureus and Escherichia coli.

• Applied Chemistry for Engineering
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• v.17 no.3
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• pp.255-259
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• 2006

Ultrafine fibers having approximately 800 nm diameter were prepared by an electrospinning method from cellulose acetate. Cellulose acetate dissolved in acetone solutions were electrospun at various conditions. The cellulose polymer solutions of various concentrations were applied under different voltages, flow rates, and tip-to-collector distances (TCD). The diameter of fibers depended on the electrospinning parameters such as its viscosity. The fibers were not formed from the polymer solutions less than 12.0 cP viscosity. The minimum diameter was 800 nm at 12.5 wt% of polymer concentration, 12 kV of voltage, $100{\mu}L/min$ of flow rate, and 7.5 cm TCD.

• Journal of the Korean Electrochemical Society
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• v.5 no.3
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• pp.117-124
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• 2002

Poly(acrylonitrile)(PAN) solutions in dimethylformamide(DMF) were electrospun to prepare webs consisting of 400nm ultra-fine fibers. The webs were oxidatively stabilized, activated by steam and resulted to be activated carbon fibers(ACFs). The specific surface area was $800\~1230 m^2/g$, which showed a trend of a decrease of the surface area with an increase in activation temperature, showing opposite behavior to the other ACFs. The activation energy of the stabilized fibers for the steam activation was determined as 29.2 kJ/mol to be relatively low indicating the easier activation than that of other carbonized fibers. The ACF webs were characterized by pore size and specific surface uea which would be related to the specific capacitance of the electrical double layer capacitor (EDLC). The specific capacitances measured were 27 F/g, 25 F/g, 22 F/g at the respective activation temperature of $700^{circ}C,\;750^{\circ}C\;800^{\circ}C$, showing similar trend with the specific surface area i.e., the higher activation temperature was, the lower specific capacitance resulted.