• Title/Summary/Keyword: UV energy

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Surface Treatment and Dyeability of Poly(phenylene sulfide) Films by UV/O3 Irradiation (UV/Ozone 조사에 의한 Poly(phenylene sulfide) 필름의 표면처리와 염색성)

  • Jang, Yong-Joon;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.23 no.4
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    • pp.284-289
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    • 2011
  • Poly(phenylene sulfide)(PPS) films were photooxidized under UV/ozone irradiation. The effect of UV energy on the surface properties of the UV-irradiation PPS films were investigated by the measurement of reflectance, surface roughness, and contact angle. Reflectance decreased at the wavelength of 400nm and the surface roughness increased with increased UV energy. The improvement in hydrophilicity with increased $O_{1s}/C_{1s}$ was caused by the introduction of hydrophilic $SO_2$ bond. Surface energy increased from 46.6 to $78.3mJ/m^2$ with increased UV energy up to $21.2J/cm^2$. Also zeta potential decreased with increased UV energy. The increased dyeability to cationic dyes may be due to the photochemically introduced anionic and dipolar dyeing sites on the PPS films surfaces.he photochemically introduced anionic and dipolar dyeing sites on the PPS films surfaces.

Photooxidation of Poly(butylene succinate) Films by UV/Ozone Irradiation (자외선/오존 조사에 의한 Poly(butylene succinate) 필름의 광산화)

  • Joo, Jin-Woo;Jang, Jinho
    • Textile Coloration and Finishing
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    • v.26 no.3
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    • pp.159-164
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    • 2014
  • Biodegradable Poly(butylene succinate), PBS, was photooxidized by UV/ozone irradiation and the effect of UV energy on the surface properties of the UV-irradiated PBS film were investigated by the measurement of reflectance, surface roughness, contact angles, chemical composition, and zeta potential. With increasing UV energy, reflectance decreased in the visible and ultraviolet regions particularly at the wavelength of 380nm. The irradiation produced nano-scale surface roughness including the maximum peak-to-valley roughness increased from 106nm for the unirradiated sample to 221nm at the UV energy of $10.6J/cm^2$. The improved hydrophilicity was due to the higher $O_{1s}/C_{1s}$ resulting from the introduction of polar groups such as C-O and C=O bonds. The surface energy of the PBS increased from $42.1mJ/m^2$ for the unirradiated PBS to $56.8mJ/m^2$ at the irradiation of $21.2J/cm^2$. The zeta potentials of the UV-irradiated PBS also decreased proportionally with increasing UV energy. The cationic dyeability of the PBS increased accordingly resulting from the improved affinity of the irradiated PBS surfaces containing photochemically introduced anionic and dipolar dyeing sites.

Decomposition of Oxalic Acid in Nitric Acid by UV Radiation (질산매질에서 UV 조사에 의한 옥살산 분해)

  • Kim, Eung-Ho;Kim, Young-Hwan;Chung, Dong-Yong;Yoo, Jae-Hyung
    • Applied Chemistry for Engineering
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    • v.8 no.1
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    • pp.108-113
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    • 1997
  • Decomposition of oxalic acid was studied in nitric acid media by using UV radiations. The UV source is Hg-lamp, emitting $2537{\AA}$ wavelength. Oxalic acid was not decomposed by itself in spite of UV radiation, but in the presence of nitric acid decomposed easily under UV radiation. It is believed that oxygen radical generated from nitrate ion by UV radiation results in the decomposition of oxalic acid. Decomposition rate of oxalic acid reached a maximum in around 0.5M $HNO_3$ and then gradually decreased with nitric acid concentration. The decrease can be also explained to be due to the reaction between oxygen radical and $NO_3{^-}$.

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Photooxidation of Poly(vinyl butyral) Films by UV/Ozone Irradiation (자외선/오존 조사에 의한 Poly(vinyl butyral)의 광산화)

  • Joo, Jin-Woo;Jang, Jinho
    • Textile Coloration and Finishing
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    • v.27 no.2
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    • pp.113-118
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    • 2015
  • Poly(vinyl butyral), PVB was photooxidized by UV/ozone irradiation and the effect of UV energy on the surface properties of the UV-irradiated PVB film were investigated by the measurement of reflectance, surface roughness, contact angles, elemental composition, and zeta potential. With increasing UV energy, reflectance decreased in the visible and ultraviolet regions particularly at the wavelength of 400nm. The irradiation produced nano-scale surface roughness including the maximum peak-to-valley roughness increased from 274nm for the unirradiated PVB to 370nm at the UV energy of $5.3J/cm^2$. The improved hydrophilicity was due to the higher $O_{1s}/C_{1s}$ resulting from the introduction of polar groups such as C=O bonds. The surface energy of the PVB film increased from $35.3mJ/m^2$ to $39.3mJ/m^2$ at the irradiation of $15.9J/cm^2$. While the zeta potentials decreased proportionally with increasing UV energy, the cationic dyeability of the PVB increased accordingly resulting from the improved affinity of the irradiated PVB surfaces containing the photochemically introduced anionic and dipolar dyeing sites.

Surface Modification of PET Irradiated by Ultra-Violet (Part I) -Transformation of Chemical Structure and Surface Properties- (UV조사를 통한 PET의 표면개질 (제1보) -화학구조 변화 및 표면특성 변화-)

  • Choi Hae Young;Lee Jung Soon
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.3_4 s.141
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    • pp.561-568
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    • 2005
  • The irradiation of Ultra-Violet (UV) is an efficient treatment for polymer to improve hydrophilic properties. 4-Channel PET knit fabrics were treated with UVA and UVC to develop functional and environment-friendly fabric. The fabric was treated with various treatment times and distances from UV lamps having different wavelength. FT-IR and XPS investigated the chemical changes. To confirm the change of surface properties, contact angle, surface energy and SEM were examined. The study of UV as a treatment for PET knit fabric shows significant changes in chemical and surface properties, which is proved by analyses. FT-IR and XPS analyses prove the augmentation of carboxylic, Hydrophilic groups on the surfaces treated by UV. The increase of water contact angle and surface energy means more water wettable and surface energy of PET film was substantially increased by UV irradiation time. The ageing after surface treatment had little influence on the surface energy of the irradiated PET film. SEM proves the surface modification of PET such as etching, bubble and crack. The negative effects are increased in accordance with increasing treatment time.

Photo-oxidation and Dyeability of Poly Ketone by UV/O3 Irradiation (자외선/오존 조사에 의한 Poly Ketone의 광산화와 염색성)

  • Kim, Min-Su;Jang, Yong-Joon;Jang, Jinho
    • Textile Coloration and Finishing
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    • v.25 no.1
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    • pp.25-29
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    • 2013
  • Poly ketone (PK) was photo-oxidized by UV/ozone irradiation and the effect of UV energy on the surface properties of the UV-irradiated PK film was investigated by the measurement of reflectance, surface roughness, contact angles, ESCA, and ATR. Reflectance, particularly at the wavelength of 380nm, decreased with increasing UV energy. And the irradiation produced nano-scale roughness on the surface uniformly. The maximum surface roughness increased from 25.3nm for the unirradiated sample to 104.9nm at the irradiation of $42.4J/cm^2$. The improvement in hydrophilicity was caused by the introduction of polar groups such as C-O and C=O bonds resulting in higher $O_{1s}/C_{1s}$. The surface energy of PK film increased from $43.3mJ/m^2$ for the unirradiated sample to $71.9mJ/m^2$ at the irradiation of $31.8J/cm^2$. The zeta potential of the UV-irradiated PK decreased with increased UV energy and the dyeability to cationic dyes increased accordingly, resulting from the photochemically introduced anionic and dipolar dyeing sites on the PK films surfaces.

Hydrophilic Modification of Poly(ethylene oxide) by UV Irradiation

  • Koo, Gwang-Hoe;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.21 no.5
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    • pp.16-20
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    • 2009
  • Films of Poly(ethylene oxide), PEO, were modified to impart hydrophilicity via UV irradiation. The UV irradiation treatment produced new photo-oxidized groups of carbonyl and ether groups as indicated in ATR and ESCA analysis. It was found that water contact angle decreased from $15^{\circ}C$ to $10^{\circ}C$ and total surface energy of PEO increased from 54.2 mN/m to 76.6 mN/m with increasing UV energy, which was attributed to significant contribution of acid base interaction of the photo-oxidized PEO rather than nonpolar interaction originating from the dominant increase in Lewis acid parameter. The increased hydrophilicity and surface energy were also proved by the decreased water wetting time.

Continuous Surface Treatment and Dyeability of PTT Film via $UV/O_3$ Irradiation (UV/Ozone 조사에 의한 PTT 필름의 연속식 표면처리와 염색성)

  • Jang Jinho;Park Dae Sun
    • Textile Coloration and Finishing
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    • v.17 no.1
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    • pp.7-13
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    • 2005
  • Continuous and intense UV irradiation on PTT film using two types of UV bulbs at different irradiation power level was carried out to modify surface characteristics of the film including zeta potential, wettability, surface energy, and dyeability. ESCA analysis of the irradiated film showed higher O/C ratio than the untreated film indicating photooxidation of outer surface layer. ATR analysis showed that the ester bonds were broken and some new groups were produced such as carboxylic acid, phenolic hydroxy, and other esters, implying that ester bonds of PTT was responsible for the observed photooxidation effect. The surface of the treated PTT film became more hydrophilic and wettable to water, coupled with increased surface energy. Polar component of the surface energy increased and nonpolar component decreased with increasing irradiation energy. The treatment also decreased zeta potential of the modified surface and nanoscale roughness increased with increasing irradiation. The dyeability of the treated films to catonic dyes was significantly improved by electrostatic and polar interaction between dye molecules and the anionic film surface. The UV irradiation seems to be a viable polymer surface modification technology, which has advantages such as no vacuum requirement and continuous process unlike plasma treatment.

Optical Properties of PVA Polarizing Films Surface-modified by UV Irradiation (자외선 조사에 의해 표면 개질된 PVA 편광필름의 광학특성)

  • Koo, Gwang-Hoe;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.18 no.6 s.91
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    • pp.49-56
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    • 2006
  • Surface treatment using UV irradiation was carried out to improve optical properties of polarizing films. The effects of UV energy of the UV-treated PVA films were investigated by measuring reflectance, surface roughness, contact angles, ESCA, and ATR. Reflectance decreased at wavelength of 450 nm or less and surface roughness increased with increasing UV energy. Water contact angle increased in the irradiated PVA films and surface energy decreased with increase in w energy. An analysis showed that the OH groups were broken and some new groups were introduced such as C=C and C=O bonds together with increased $O_{1s}/C_{1s}$, resulting in the observed surface modification effect. Surface modified PVA polarizing films showed improvement in light transmittance of polarizing films at high wavelength region without deteriorating polarization efficiency, which was not affected by UV irradiation sequence during manufacturing processes such as coloring and drawing.