• 멤브레인
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• 제29권3호
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• pp.140-146
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• 2019

본 연구에서는 다공성 Polyacrylonitrile (PAN) 중공사막을 지지체막으로 하여 Poly styrene sulfonic acid (PSSA)와 polyethyleneimine (PEI)을 이용하여 layer-by-layer법으로 선택층을 형성시켰다. 코팅용액에 Mg염을 첨가하여 염석법(salting out method)을 이용하였다. 코팅용액의 이온세기, 고분자 농도, 코팅시간 등을 달리하여 나노여과막을 제조하였으며 NaCl, $MgCl_2$, $CaSO_4$ 100 mg/L를 공급액으로 하여 2 atm의 구동 압력에서 투과도와 염 배제율을 평가하였다. PSSA 20,000 ppm, 코팅시간 3분, 이온세기 1.0, PEI 30,000 ppm, 코팅시간 1분, 이온세기 0.1의 조건으로 코팅한 막이 가장 우수한 성능을 보여 주었다. 100 ppm의 NaCl, $MgCl_2$, $CaSO_4$ 공급액에서 각각 20.4, 19.4, 18.7 LMH의 투과도와 67, 90, 66.6%의 염 배제율을 나타내었다.

• 방사선산업학회지
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• 제17권2호
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• pp.173-181
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• 2023

3D printing is a technology that can transform and process computerized data obtained through modeling or 3D scanning via CAD. In the medical field, studies on customized 3D printing technology for clinical use or patients and diseases continue. The importance of research on filaments and molding methods is increasing, but research on manufacturing methods and available raw materials is not being actively conducted. In this study, we compare the characteristics of each material according to the manufacturing method of the phantom manufactured with 3D printing technology and evaluate its usefulness. We manufactured phantoms of the same size using poly methyl meta acrylate (PMMA), acrylonitrile butadiene styrene (ABS), and Poly Lactic Acid (PLA) based on the international standard phantom of aluminum step wedge. We used SITEC's radiation generator (DigiRAD-FPC R-1000-150) and compared the shielding rate and line attenuation coefficient through the average after shooting 10 times. As a result, in the case of the measured dose transmitted through each phantom, it was confirmed that the appearance of the dose measured for phantoms decreased linearly as the thickness increased under each condition. The sensitivity also decreased as the steps increased for each phantom and confirmed that it was different depending on the thickness and material. Through this study, we confirmed that 3D printing technology can be usefully used for phantom production in the medical field. If further development of printing technology and studies on various materials are conducted, it is believed that they will contribute to the development of the medical research environment.

• 폴리머
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• 제24권2호
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• pp.276-280
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• 2000

폴리아크릴로니트릴 (PAN) 직물을 매트릭스로 하여 전도성고분자인 폴리피롤(PPy)과 전도성 복합재료 직물을 제조하였다. 복합재료의 제조는 PAN 직물을 피롤과 산화제를 포함하는 용액에 일정 시간동안 함침하여 직물상에서 전도성 고분자의 중합을 in-situ로 유도하는 방법을 이용하였다. 복합재료의 물성을 최적화 하기 위한 반응 조건을 설정하였으며, 이때 arylsulfonate 계통의 도판트를 부가적으로 첨가하여 이들이 복합재료의 물성에 미치는 영향을 검토하였다. 본 연구에서 실험한 다양한 종류의 도판트 중에서 antraquinonesulfonate (AQSA)가 부가적으로 첨가된 전도성 PAN 직물이 가장 우수한 전기전도도와 열적 안정성 및 세탁 견뢰도를 나타내었다.

• Carbon letters
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• 제20권
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• pp.53-61
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• 2016

The reportedly synergistic effects of carbon nanotubes (CNTs) and graphene hybrids have prompted strong demand for an efficient modifier to enhance their dispersion. Here, we investigated the ability of poly(acrylonitrile) (PAN) to overcome the van der Waals interaction of multi-walled CNTs (MWCNTs) and graphene by employing a simple wrapping process involving ultrasonication and subsequent centrifugation of PAN/MWCNT/graphene solutions. The physical wrapping of MWCNTs and graphene with PAN was investigated for various PAN concentrations, in an attempt to simplify and improve the polymer-wrapping process. Transmission electron microscopy analysis confirmed the wrapping of the MWCNTs and graphene with PAN layers. The interaction between the graphitic structure and the PAN molecules was examined using proton nuclear magnetic resonance, ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, and Raman spectroscopy. The obtained results revealed that the cyano groups of the PAN molecules facilitated adhesion of the PAN molecules to the MWCNTs and graphene for polymer wrapping. The resulting enhanced dispersion of MWCNTs and graphene was verified from zeta potential and shelf-life measurements.

• 한국염색가공학회지
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• 제25권2호
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• pp.94-101
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• 2013

Poly(acrylonitrile) (PAN) nanofibers containing different amounts of titanium dioxide ($TiO_2$) have been prepared by electrospinning technique. Photocatalytic activity of these electrospun PAN/$TiO_2$ nanofibers and the effect of $TiO_2$ content on the photocatalytic efficiency of PAN/$TiO_2$ nanofibers have been evaluated by monitoring the photodecomposition of fluorescein dye, rhodamine B and methylene blue under UV irradiation with respect to irradiation time. Moreover, the effect of hydrogen peroxide ($H_2O_2$) on the photocatalytic behavior of PAN/$TiO_2$ nanofibers has also been investigated. The results showed that PAN/$TiO_2$ nanofibers are effective photocatalyst and their photocatalytic efficiency increases with the increase of $TiO_2$ content in the PAN/$TiO_2$ nanofibers. It is also observed that the presence of $H_2O_2$ significantly enhances the photocatalytic ability of PAN/$TiO_2$ nanofibers. The morphology and the photocatalytic behavior of the PAN/$TiO_2$ nanofibers containing different amounts of $TiO_2$ nanoparticles have been investigated by field-emission scanning electron microscopy (FE-SEM) and UV/Visible spectroscopy, respectively.

• 멤브레인
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• 제18권3호
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• pp.256-259
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• 2008

본 연구에서는 poly(acrylonitrile-butadiene-styrene) (ABS)에 carbon graphite와 zeolite 4A를 첨가하여 복합 필름을 제조하고 공기와 수증기 투과 특성을 살펴보았다. 복합 필름의 경우 모든 경우에서 순수한 ABS에 비해서 산소와 질소의 투과도가 감소하였으며, 산소의 투과도 감소가 질소의 투과도 감소보다 약간 큰 관계로 산소/질소 선택도도 조금 감소하였다. 또한, 수증기 투과도도 순수한 ABS에 비해서 약 1/2로 감소하였다. 이러한 투과도의 감소는 ABS에 filler를 첨가함으로 인하여 물질 확산 경로의 tortuosity가 증가했기 때문인 것으로 생각된다.

• 공업화학
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• 제7권4호
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• pp.777-786
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• 1996

Seed 중합 방법에 의하여 단분산성 다공의 폴리아크릴로니트릴-에틸렌글리콜 디메타크릴레이트 (PAN) 고분자 마이크로 겔이 제조되었다. PAN 마이크로 겔의 물리적인 특성을 모노머/seed와 희석제/모노머의 비율, 가교제의 농도 및 희석제의 종류에 따라 연구하였다. PAN 마이크로 겔의 입도 분포는 모노머/seed의 비율이 50 이하 일 때 단분산성을 나타냈으며, 가교제의 농도가 증가할수록 입자 내부의 미소 구체 (microsphere)의 크기가 작아져 더욱 밀집된 형태를 나타내기 때문에 입자의 비표면적이 증대되었다. 또한 희석제로 톨루엔을 사용하고 희석제/모노머의 비율이 1.0일 때 입자표면의 세공이 가장 발달되었다.

• EDISON SW 활용 경진대회 논문집
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• 제4회(2015년)
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• pp.304-307
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• 2015

Carbon nanotubes (CNTs) have been widely accepted and used as the enhancer for polymer nano-composites due to their remarkable mechanical properties. Understandably, the CNT fiber-polymer matrix interface plays a major role in determining the properties of the CNT-polymer nano-composites. Here, using the LCAODFT Lab tool available on the EDISON Nano-Physics site, we performed first-principles density-functional theory calculations to determine the atomic configurations and binding energies of the CNTs in contact with polymers. For the polymer matrixes, we chose poly(acrylonitrile) (PAN), which is one of the most well-known polymer matrixes for the carbon nanofiber nanocomposites. Different chiralities and diameters of pristine CNTs were considered, and several PAN-CNT configurations were prepared based on the atomistic positions and directions of cyano group in PAN. The most favorable configuration of PAN was obtained when the PAN bound parallel to the surface of CNT. Our finding indicates the binding configurations are determined by the direction of the cyano group dominantly rather than the atomistic position of PAN, or the symmetry of CNTs. The result of increasing the length of CNT diameter suggests that PAN is inclinable to align evenly on the surface of relatively large size of CNT with the configuration parallel to the surface. These results obtained in this study will provide the starting point for the design of improved PAN-CNT composites for the next-generation ultra-strong and ultra-light carbon nanofibers.

• Macromolecular Research
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• 제17권6호
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• pp.417-423
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• 2009

The effects of maleic anhydride-grafted polypropylene (PP-g-MAH) addition on polypropylene (PP) and poly(acrylonitrile-butadiene-styrene) (ABS) blends were studied. Blends of PP/ABS (70/30, wt%) with PP-g-MAH were prepared by a twin-screw extruder. From the results of mechanical testing, the impact, tensile and flexural strengths of the blends were maximized at a PP-g-MAH content 3 phr. The increased mechanical strength of the blends with the PP-g-MAH addition was attributed to the compatibilizing effect of the PP and ABS blends. In the morphological studies, the droplet size of ABS was minimized (6.6 ${\mu}m$) at a PP-g-MAH content of 3 phr. From the rheological examination, the complex viscosity was maximized at a PP-g-MAH content of 3 phr. These mechanical, morphological and rheological results indicated that the compatibility of the PP/ABS (70/30) blends is increased with PP-g-MAH addition to an optimum blend at a PP-g-MAH content of 3 phr.

• Macromolecular Research
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• 제8권2호
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• pp.95-101
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• 2000

Clay/poly(styrene-co-acrylonitrile) copolymer (SAN) hybrids have been prepared by simple meltmixing of two components, SAN and organophilic clays with a twin screw extruder. Effects of intercalant on the dispersibility of silicate layers in clay-dispersed nanocomposite were studied by using five different organophilic clays modified with the intercalants of different chemical structures and different fractions of intercalant. The dispersibility of 10-$\AA$-thick silicate layers of clay in the hybrid was investigated by using an X-ray diffractometer and a transmission electron microscope. It was found that if the fraction of intercalant in the organophilic clay becomes too high, SAN is difficult to intercalate into the inter-gallery of silicate layers in the hybrid prepared at 180$\^{C}$, and thus the hybrid shows poor dispersibility of silicate layers. The flexural modulus of the hybrid increases as the dispersibility of silicate layers in the hybrid increases.