• Macromolecular Research
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• 제11권6호
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• pp.495-500
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• 2003

UV-induced graft polymerization of glycidyl methacrylate (GMA) to a polypropylene (PP) membrane was carried out in the vapor phase with benzophenone (BP) as a photoinitiator. Attenuated total reflection Fourier transform infrared spectroscopy, atomic force microscopy (AFM), and scanning electron microscopy (SEM) were utilized to characterize the copolymer. The degree of grafting increased with increasing reaction time, increased UV irradiation source intensity, and increased immersion concentration of the BP solution. The optimum synthetic condition for the PP-g-GMA membrane was obtained with a reaction time of 2 hrs, a UV irradiation source intensity of 450 W, and an immersion concentration of the BP solution of 0.5 mol/L. The pure water flux decreased upon increasing the degree of grafting and increasing the amount of diethylamino functional group introduced. The analysis of AFM and SEM images shows that the graft chains and diethylamino groups of PP-g-GMA grew on the PP membrane surface, resulting in a change in surface morphology.

• 공업화학
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• 제3권1호
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• pp.172-178
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• 1992

$F^{3+}(FeCl_3{\cdot}6H_2O)$을 광증감제로 하여 Chitosan 필름에 아크릴로니트릴 단량체를 수용액상에서 자외선 조사하여 그라프트 공중합시켰다. 그라프트 공중합체의 확인은 IR 스펙트럼과 전자 현미경으로 행하였다. 단량체의 농도, 광증감제의 농도, 중합반응시간, 중합반응온도 등 여러 중합반응의 파라미터를 조사하였다. 단량체의 농도와 광증감제의 농도가 증가할수록 퍼센트 그라프팅은 증가하였으며 중합반응시간과 중합반응온도가 증가하여도 퍼센트 그라프팅은 증가하였다.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2011년도 제44차 학술발표회
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• pp.31-31
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• 2011

Lanasol dyes containing ${\alpha}$-bromoacrylamide or ${\alpha},{\beta}$-dibromopropionylamide group are used for wool dyeing. They are normally applied to wool under pH 4.5 to 6.5 at $100^{\circ}C$. Although wool fabric can be dyed to obtain deep colour, high light and wet fastness, the dyeing processes need long dyeing time at high temperature, with salt addition, which inevitably causes environmental problems. Grafting is a modification method for textile where monomers are covalently bonded onto the polymer chain. It can be initiated by ozone, ${\gamma}$ rays, electron beams, plasma, corona discharge and UV irradiation. Coloration by UV-induced photografting exhibits several advantages such as fast reaction rate, energy saving, simple equipment, easy exploitation and environmentally friendliness. Also it requires much lower energy compared to the conventional dyeing and less damage to the substrate. In this study, a direct sequential UV-induced photografting onto wool fabrics was discussed. To understand the graft polymerization mechanism further, several characterization methods were used. Moreover, the effects of several principal factors on the graft photopolymerization were investigated. Furthermore, the colorfastness results were compared with conventional dyeing methods.

• Korean Chemical Engineering Research
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• 제57권3호
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• pp.392-399
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• 2019

A highly transparent interfacial layer (HTIL) to enhance the performance of dye-sensitized solar cells (DSSCs) was prepared via a polymer-assisted (PA) approach. Poly(vinyl chloride)-graft-poly(oxyethylene methacrylate) (PVC-g-POEM) was synthesized via atom-transfer radical polymerization (ATRP) and was used as a sacrificial template. The PVC-g-POEM graft copolymer induced partial coordination of a hydrophilic titanium isopropoxide (TTIP) sol-gel solution with the POEM domain, resulting in microphase separation, and in turn, the generation of mesopores upon calcination. These phenomena were confirmed using Fourier-transform infrared (FT-IR) spectroscopy, UV-visible light transmittance spectroscopy, scanning electron microscopy (SEM), and X-ray diffraction (XRD) analysis. The DSSCs incorporating HTIL60/20 (consisting of a top layer with a pore size of 60 nm and a bottom layer with a pore size of 20 nm) exhibited the best overall conversion efficiency (6.36%) among the tested samples, which was 25.9% higher than that of a conventional blocking layer (BL). DSSC was further characterized using the Nyquist plot and incident-photon to electron conversion efficiency (IPCE) spectra.

• 한국막학회:학술대회논문집
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• 한국막학회 1998년도 춘계 총회 및 학술발표회
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• pp.99-101
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• 1998

1. Introduction : The conventional grafting polymerization technique requires chemically reactive groups on the surface as well as on the polymer chains. For this reason, a series of prefunctionalization steps are necessary for covalent grafting. The surface prefunctionalizational technique for grafting can be used to ionization radiation, UV, plasma, ion beam or chemical initiators. Of these techniques, radiation method is one of the useful methods because of uniform and rapid creation of active radical sites without catalytic contamination in grafted samples. If the diffusion of monomer into polymer is large enough to come to the inside of polymer substrate, a homogeneous and uniform grafting reaction can be carried out throughout the whole polymer substrate. Radiation-induced grafting method may attach specific functional moieties to a polymeric substrate, such as preirradiation and simultaneous irradiation. The former is irradiated at backbone polymer in vacuum or nitrogen gas and air, and then subsequent monomer grafting by trapped or peroxy radicals, while the latter is irradiated at backbone polymer in the presence of the monomer. Therefore, radiation-induced polymerization can be used to modification of the chemical and physical properties of the polymeric materials and has attracted considerable interest because it imparts desirable properties such as blood compatibility. membrane quality, ion excahnge, dyeability, protein adsorption, and immobilization of bioactive materials. Synthesizing biocompatible materials by radiation method such as preirradiation or simultaneous irradiation has often used $\gamma$-rays to graft hydrophilic monomers onto hydrophobic polymer substrates. In this work, in attempt to produce surfaces that show low levels of anti-fouling of bovine serum albumin(BSA) solutions, hydroxyethyl methacrylate(HEMA) was grafted polypropylene membrane surfaces by preirradiation technique. The anti-fouling effect of the polypropylene membrane after grafting was examined by permeation BSA solution.

• 폴리머
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• 제28권5호
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• pp.397-403
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• 2004

광개시제를 이용한 UV 조사방법으로 설폰화 PET-g-GMA 극세 이온 교환 섬유를 합성하고 이들의 구조 및 흡착 특성을 확인하였다. PET-g-GMA의 그라프트율은 UV 조사량, 조사시간 및 반응온도가 증가함에 따라 증가하였으며, 최적 합성조건은 UV조사량, 시간, 반응온도가 각각 450 W, 60 min, $40^{\circ}C$이었다. 한편 최대 설폰화율과 이온 교환 용량은 각각 8.12 mmol/g, 3.25 meq/g의 값을 나타내었다. 또한 설폰화 PET-g-GMA 극세 이온 교환 섬유의 인장강도는 반응전 PET 기재의 인장강도보다 그라프트 반응율이 증가함에 따라 약간 낮아지는 경향을 보였다. 설폰화 PET-g-GMA 극세 이온 교환 섬유의 칼슘 이온, 마그네슘 이온에 대한 흡착 시험 결과 마그네슘 이온이 칼슘 이온보다 흡착 파과 시간이 길었으며, 칼슘 이온, 마그네슘 혼합 용액에서 마그네슘의 흡착 파과 시간은 더욱 길어지는 경향을 보였다.