• Textile Coloration and Finishing
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• v.21 no.4
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• pp.46-56
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• 2009

In order to establish the standard manufacturing condition of PET flame retardant sheets, physicochetnical properties of the samples made by the conventional flame-retardant finishing were systematically investigated, including compatibility among flame retardant agent and finishing auxiliaries, surface property, and wicking property. From this results, the addition of washing and renapping process after the shearing process was required for the more effective in producing PET flame-retardant sheet by the standard finishing. The effect of the modification of the regular flame retardant finishing process was studied by FTIR, TGA, and flame retardancy test.

• Macromolecular Research
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• v.16 no.3
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• pp.212-217
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• 2008

PVDF ($Kynar^{(R)}$ 761) nanofibers were made by electrospinning with an external voltage of 6-10 kV, a traveling distance of 7-15 cm and a flow rate of 0.4-1 mL/h. Although the mean diameter of the fibers has not changed significantly, the conditions affected the change in diameter distribution. This was attributed to interactions, both attraction and repulsion, between the positive charges on the polymer solutions and the electrically grounded collector. Higher voltages and traveling distance increased the level of attraction between the positive charge on the polymer solution and the electrically grounded collector, resulting in a narrow diameter distribution, In addition, a high flow rate allowed a high population of uniformly charged solutions to travel to the grounded collector, which resulted in a narrow diameter distribution. The optimum conditions for electrospinning of PVDF in DMAc/acetone (3/7 by wt) were a collector voltage of 6 kV, a syringe tip to collector of 7 cm, a flux rate of 0.4 mL/h and 10 kV, 10 cm, 1 mL/h, Since PVDF is widely used as a filtration membrane, it was electrospun on a PET support with a rotating drum as a grounded collector. Surprisingly, some straight nanofibers were separated from the randomly deposited nanofibers. The straight nanofiber area was transparent, while the randomly deposited nanofiber area was opaque. Both straight nanofibers and aligned nanotibers could be obtained by manipulating the PET drum collector. These phenomena were not observed when the support was changed to an Al sheet. This suggests that a pseudo dual collector was generated on the PET sheet. No negative charge was created because the PET sheet was not a conductive material. However, less charge was created when the sheet was not perfectly attached to the metal drum. Hence, the nanotibers jumped from one grounded site to the nearest one, yielding a straight nanofiber.

• Journal of the Korean institute of surface engineering
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• v.39 no.1
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• pp.9-12
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• 2006

Al-doped ZnO(AZO)/Ag/AZO multi-layer films deposited on PET substrate by RF magnetron sputtering have a much better electrical properties than Al-doped ZnO single-layer films. The multi-layer structure consisted of three layers, AZO/Ag/AZO, the optimum thickness of Ag layers was determined to be $112{\AA}$ for high optical transmittance and good electrical conductivity. With about $1800{\AA}$ thick AZO films, the multi-layer showed a high optical transmittance in the visible range of the spectrum. The electrical and optical properties of AZO/Ag/AZO were changed mainly by thickness of Ag layers. A high quality transparent electrode, having a resistance as low as $6\;W/{\square}$ and a high optical transmittance of 87% at 550 nm, was obtained by controlling Ag deposition parameters.