• Title/Summary/Keyword: polyacrylonitrile

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The Preparation of Polyacrylonitrile Diagnostic Membranes for Blood Glucose Measurements (2) : Effects of Blood Constituents on the Measurements of Glucose Concentration (혈당측정을 위한 폴리아크릴로니트릴 진단막의 제조(2) : 혈액속의 성분들이 글루코우즈의 농도 측정에 미치는 영향)

  • Kwon, Suk-Ky;Choi, Mi-Ok
    • Membrane Journal
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    • v.18 no.4
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    • pp.268-273
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    • 2008
  • Diagnostics membranes which were made of polyacrylonitrile were prepared for the measurements of blood glucose concentration. Final absorbances at 680nm through polyacrylonitrile diagnostic membranes were measured at various concentration of glucose in blood. It was found that the end-point results of varing absorbance values as time (K/S) had a linear relationship toward the blood glucose concentration. The effects of possible constituents in human blood on the glucose concentration measurements were examined. As a result, most of the chemicals did not affect seriously on the blood glucose measurements.

Removal of Cu and Sr Ions using Adsorbent Obtained by Immobilizing Zeolite Synthesized from Jeju Volcanic Rocks in Polyacrylonitrile (제주 화산석으로 합성한 제올라이트를 Polyacrylonitrile에 고정화한 흡착제를 이용한 구리와 스트론튬 이온의 제거)

  • Lee, Chang-Han;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.27 no.12
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    • pp.1215-1226
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    • 2018
  • In this study, PAN-SZ (polyacrylonitrile scoria zeolite) beads were prepared by immobilizing Na-A zeolite (SZ-A) synthesized from Jeju volcanic rocks (scoria) on the polymer PAN. FT-IR and TGA analysis results confirmed that the SZ-A was immobilized in the PAN-SZ beads. SEM images showed that the PAN-SZ beads are a spherical shape with 2 mm diameter and exhibit a porous inner structure inside the bead. The most suitable mixing ratio of PAN to SZ-A as the adsorbent for removing Sr ions was PAN/SZ-A = 0.2 g/0.3 g. The adsorption kinetic data for Cu and Sr ions were fitted well with the pseudo-second-order model. The Cu and Sr ion uptakes followed a Langmuir isotherm model and the maximum adsorption capacities at $20^{\circ}C$ were 84.03 mg/g and 75.19 mg/g, respectively. The amount of Sr ion adsorbed by SZ-A on the PAN-SZ beads was about 160 mg/g, which was similar to that adsorbed by SZ-A powder. Thus, the PAN-SZ beads prepared in this study are considered to be effective adsorbents for removing metal ions in aqueous solutions.

Characterization of a New Poly(acrylonitrile-itaconate) based Gel-electrolyte (새로운 poly(acrylonitrile-itaconate)공중합체를 기초로 한 젤-전해질의 특성)

  • Choi B. K.;Kim S. H.;Gong M. S.
    • Journal of the Korean Electrochemical Society
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    • v.3 no.3
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    • pp.169-172
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    • 2000
  • A new gel polymer electrolyte based on the modified polyacrylonitrile (PAN), polyacrylonitrile-co-bis[2-(2-methoxyethoxy)ethyl]itaconate (abbreviated as PANI) copolymer was synthesized in expectation of enhanced trapping ability of liquid electrolytes. PAN and PANI blend was complexed with organic solvents, ethylene carbonate (EC) and dimethyl carbonate (DMC), and $LiClO_4$ salt. The highest room temperature conductivity of $2\times10^{-3}\;Scm^{-1}$ was found for a film of 25PAN+10PANl+50EC/DMC+$15LiClO_4$. The solvent-rich crystalline part decreases due to the blending of PANI and therefore number of charge carriers increases giving higher ionic conductivity. The addition of PAM as a host polymer in the PAN-based gels has beneficial effects such as higher ionic conductivity, better thermal characteristics, better miscibility with solvent, wider electrochemical stability, and better interfacial stability with lithium electrode, though it exhibits slightly less mechanical rigidity.

Studies on Polyacrylonitrile (2) Thermal Degradation of Polyacrylonitrile (폴리아크릴로니트릴에 關한 硏究 (第 2 報) 폴리아크릴로니트릴의 熱分解에 關하여)

  • ICK SAM NOH
    • Journal of the Korean Chemical Society
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    • v.11 no.2
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    • pp.70-76
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    • 1967
  • Structural changes attending polyacrylonitrile(PAN) upon heating and treating with nucleophilic reagents have been studied for some time and a few authors have studied on the thermal degradation, particularly on the characterization of degradation products in PAN. It is the purpose of this paper to report the kinetic study on the thermal degradation above $250^{\circ}C$ and make some suggestions as to the degradation process and mechanism in PAN. The degradation process in PAN is considered that three reactions are combined in two steps. Random chain scission accompanying the naphthylidine-type ring formation is the first step and the degradation of naphthylidine-type ring occurred as the next step. The reactions in the first step are competitive so that the maximum weight loss on pyrolysis of PAN, under such a condition that the degradation of naphthylidine-type ring is negligible, is depended on the relative reaction rate of these two competitive reactions.

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A Study on Stabilization and Mechanical Properties of Polyacrylonitrile-based Fiber with Itaconic acid (이타콘산을 함유한 폴리아크릴로니트릴계 전구체섬유의 열안정화 및 그 물성에 관한 연구)

  • 신익기;이신희;박수민
    • Textile Coloration and Finishing
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    • v.15 no.2
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    • pp.76-85
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    • 2003
  • In this study, a continuous stabilization process is used to make high-performance carbon fiber from polyacrylonitrile(PAM)-based fibers. The effect of oxygen content of PAN-based fiber on the stabilization process and the properties of the resultant carbon fibers is investigated. In order to research the progress of stabilization reaction FT-IR, elemental analysis, density, DSC, etc are used. Stabilization is carried out in air atmosphere from the 200 to $300^\circ{C}$ temperature range. An increase of PAN-based fibers diameter reduces the oxygen content during the continuous stabilization process. A higher oxygen content increase the density, tensile strength and modulus in the resultant carbon fibers. The most appropriate oxygen content in the stabilized fiber should be about 12%. Fibers having more than 2% oxygen content yield carbon fibers with inferior properties. Those carbon fibers also have sufficient commercial availability.

Grafting of Casein onto Polyacrylonitrile Fiber for Surface Modification

  • Jia Zhao;Du Shanyi
    • Fibers and Polymers
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    • v.7 no.3
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    • pp.235-240
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    • 2006
  • Polyacrylonitrile (PAN) fiber was grafted with casein after alkaline hydrolysis and chlorination reactions of the original fiber. The structures and morphologies of the casein grafted fiber were characterized by Fourier transform infrared spectroscopy (FTIR), X-Ray diffraction (XRD), and scanning electron microscope (SEM). Moisture absorption, specific electric resistance, water retention value, and mechanical properties were also investigated. The results showed that casein was grafted onto the surface of the PAN fiber and the grafted PAN fiber presented better hygroscopicity compared with the untreated fiber. With proper tensile strength, the modified fiber could still meet the requirement for wearing. A mechanism was proposed to explain the deposit of casein on the synthetic acrylic fiber.

Properties of Polyacrylonitrile/Single Wall Carbon Nanotube Composite Films Prepared in Nitric Acid

  • Kim Seong Hoon;Min Byung Gil;Lee Sang Cheol
    • Fibers and Polymers
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    • v.6 no.2
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    • pp.108-112
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    • 2005
  • Nanocomposite films were prepared by casting the solution of polyacrylonitrile (PAN) and single wall nanotube (SWNT) in nitric acid subsequent to sonication. Even though SWNT shows good dispersion visually, the reinforcing effect was not satisfactory. The G-band Raman spectra of the drawn film clearly demonstrated that SWNTs in the film are well-oriented along the drawing axis of the film. The electrical resistivity of the film prepared using nitric acid was lower than that of the film using DMF. Thus, nitric acid is presumably more effective in dispersing nanotubes than DMF.

Effect of Viscosity on the Morphology of Electrospun Polyacrylonitrile Fibers as a Linear Actuator and Artificial Muscles

  • Kim, Ye-Na;Lee, Deuk-Yong;Lee, Myung-Hyun;Lee, Se-Jong
    • Journal of the Korean Ceramic Society
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    • v.43 no.4 s.287
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    • pp.203-206
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    • 2006
  • Polyacrylonitrile (PAN) nanofibers, which are pH-sensitive and exhibit soft actuation as a linear actuator and artificial muscles, were prepared by electrospinning to investigate the effect of viscosity on the morphology of PAN fibers. Experimental results revealed that higher viscosity is critical for the formation of unbeaded nanofibers because surface tension is almost constant throughout the experiment. Uniform, smooth, and continuous fibers with diameters of about 700 nm were achieved for the 10 wt% PAN fibers at a flow rate of 0.5 mL/h and an electric field of 0.875 kV/cm.

Investigation on Polyacrylonitrile/Cellulose Acetate Blends

  • Barani, Hossein;Bahranmi, Seyad Hajir
    • Macromolecular Research
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    • v.15 no.7
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    • pp.605-609
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    • 2007
  • The molecular interactions of polyacrylonitrile (PAN) and cellulose acetate (CA) were investigated thoroughly via dilute solution viscometry in dimethylformamide (DMF) as a common solvent at $30^{\circ}C$. The intrinsic viscosities and viscometric interaction parameters were experimentally determined for both binary (polymer/dimethylformamide) and ternary (PAN/CA/dimethylformamide) systems. As all investigated PAN/CA ternaries evidenced negative viscometric interaction parameter values $({\Delta}b\;&{\Delta}k<0)$, the existence of repulsive intermolecular interactions was deduced, and PAN/CA blends were assigned as immiscible. Moreover, the results of microscopy photograph analysis indicated that pure PAN film evidences a homophasic structure, and the size of the phase domain increases gradually with increases in CA. In DSC analysis, it was determined that the glass transition temperature of the blend film increased slightly with increases in the CA content of the blend film.

Synthesis of Polyacrylonitrile as Precursor for High-Performance Ultrafine Fibrids

  • Kim, Subong;Kuk, Yun-Su;Jin, Fan-Long;Park, Soo-Jin
    • Bulletin of the Korean Chemical Society
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    • v.35 no.2
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    • pp.407-414
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    • 2014
  • Polyacrylonitrile (PAN) copolymers with different methyl acrylate (MA) contents were synthesized via solution polymerization and used as precursors for high-performance PAN ultrafine fibrids. The chemical structures of the copolymers were characterized using Fourier-transform infrared spectroscopy and $^{13}C$ nuclear magnetic resonance spectroscopy. Their particle sizes and aspect ratios increased with increasing viscosity, and the degree of crystallinity increased with decreasing concentration of copolymer solution. In contrast, their peak temperature and heat of exotherm increased with decreasing concentration of the copolymer solution. The aromatization indices (AIs) of the fibrids increased with increasing heat-treatment time; however, the AIs decreased when the heat-treatment temperature was higher than the onset temperature of the copolymers. On the other hand, the crystal sizes of the fibrids decreased with increasing concentration of the copolymer solution when the MA content was held constant.