• Tribology and Lubricants
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• v.25 no.3
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• pp.176-181
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• 2009

Aminated polyacrylonitrile as the new organic disperse phases of the anhydrous ER fluid has been synthesized and ER effect of the suspension composed of aminated polyacrylonitrile in silicone oil investigated. The suspension showed a typical ER response (Bingham flow behavior) upon application of an electric field. The shear stress for the suspension exhibited the dependence with a factor equals to 1.6 power on theelectric field. The current density and the conductivity of the of aminated polyacrylonitrile suspension increase with the electric field intensity and moreover the conductivity of the suspension is about 8 order of magnitude higher than that of the silicone oil. On the basis of the the results, aminated polyacrylonitrile suspension showed the ER flow behavior upon application of the electric field due to the polarizability of the branched amine polar group of the aminated polyacrylonitrile particles.

• Journal of Korea Foresty Energy
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• v.17 no.1
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• pp.30-35
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• 1998

The cellulose modification can be made in steps, giving a range of new products having properties quite different from the parent cellulose. Effective molecular weight control and narrow molecular weight distribution of the polyacrylonitrile can be accomplished by anionic polymerization technique. Preformed polyacrylonitrile was grafted precisely onto cellulose acetate by SN$_2$ reaction mechanism in a simple and effective way under homogeneous reaction condition. The 3.5g of completely dried cellulose acetate(DS=2.4) dissolved in 50ml of dry THF was transferred to the 215m1 polyacrylonitrile solution. The mixture was stirred vigorously under nitrogen atmosphere for 2 hrs. FTIR spectra of cellulose acetate and grafted cellulose acetate were taken, and their characteristic bands were identified.

• Polymer(Korea)
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• v.35 no.3
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• pp.232-237
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• 2011

The relaxation spectra of polyacrylonitrile-poly(vinyl chloride) copolymer filament fibers were obtained by applying the experimental stress relaxation curves to the theoretical equation of relaxation spectrum. The theoretical equation of relaxation spectrum was derived from the Ree-Eyring and Maxwell model. The experimental of stress relaxation was carried out using a tensile tester with a solvent chamber. The determination of relaxation spectra was performed by computer calculation. From the relaxation spectra, the fine structures, viscoelastic properties and hole volumes of solid polymers were studied. It was observed that the relaxation spectra of these samples were directly related to the distribution of molecular weights and self diffusions of flow segments.

• Journal of the Korean Chemical Society
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• v.11 no.2
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• pp.77-80
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• 1967

Radiolysis of polyacrylonitrile(PAN) has been studied. Parameters for crosslinking and scission induced by gamma-ray irradiation were obtained by means of sol-gel partitioning method. G-value of crosslinking in PAN ($\bar{M}n=6{\times}10^5$) was 0.038 and the gel dose 21.6 Mrad. The effects of irradiation on the thermal degradation rate in PAN was also studied. No appreciable changes in thermal degradation rate observed up to 81.8 Mrad of irradiation dose.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.279-280
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• 2003

아크릴계 섬유를 포함하여 기존 섬유의 새로운 용도 창출 및 부가가치를 높이기 위하여 특수한 기능성을 나타내는 섬유들에 대한 관심이 꾸준히 증가하고 있다[1]. 이러한 이유로 유기물질과 무기물질의 복합체 제조는 일찍이 1980년대 초부터 연구되고 있고, 새로운 성능 및 기능 화대를 목표로 계속 이루어지고 있다[2]. 폴리아크릴로니트릴(Polyacrylonitrile, PAN)은 용액방사를 하는 대표적인 합성섬유로 담요, 카페트, 커튼 등 다양한 제품으로 응용되고 있으며, 그 성질이 천연섬유인 양모와 유사하기 때문에 양모 대체용으로 많이 사용되고 있다[1]. (중략)

• Carbon letters
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• v.24
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• pp.36-40
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• 2017

Polyacrylonitrile/pitch nanofibers were prepared by electrospinning as a precursor for a gas sensor material. Pitch nanofibers were properly fabricated by incorporating polyacrylonitrile as an electrospinning supplement component. Polyacrylonitrile/pitch nanofibers were activated with steam at various temperatures followed by subsequent carbonization to make carbon nanofibers with a highly conductive graphitic structure. Steam activation was effective in facilitating gas adsorption onto the carbon nanofibers due to the increased surface area. The carbon nanofibers activated at $800^{\circ}C$ had a larger surface area and a lower micro pore fraction resulting in a higher variation in electrical resistance for improved CO gas sensing properties.

• Membrane Journal
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• v.19 no.3
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• pp.222-227
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• 2009

Polyacrylonitrile diagnostic membranes were prepared to make blood-glucose self-checking system for diabetics. After the prepared polyacrylonitrile membranes were stored at sereval different environments, final absorbances at 680 nm were measured at various concentration in blood. The mesured blood-glucose level did not show the big differences at the various storage temperatures. It was found that the blood-glucose level decreased a little bit compared to the standard value after $10{\sim}30$ hours at high humidities.

• Membrane Journal
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• v.17 no.4
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• pp.369-374
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• 2007

Polyacrylonitrile diagnostic membranes were prepared to measure blood glucose level of diabetics. Final absorbances at 680 nm through activated polyacrylonitrile membranes were measured at various concentration of glucose in plasma. The end-point results of K/S values obtained from the absorbances had a linear relationship toward the glucose concentration. The effect of temperature on the measurements of glucose concentration was studied. The stability of polyacrlonitrile diagnostic membranes was examined at RH 80%.

• Polymer(Korea)
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• v.32 no.2
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• pp.150-156
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• 2008

Two different polyacrylonitrile samples (PANs, triad tacticity fraction is 0.25 and 0.64) were synthesized and used to study the kinetics of cyclization. Polymers were treated at different temperatures between 250 to $300^{\circ}C$ under air atmosphere, and analyzed by X-ray diffractometer. The sharp and strong peak at $2{\theta}=16.5^{\circ}$ corresponds to a lateral repeat distance that is the (100) diffraction in hexagonal lattice, while the peak at $2{\theta}=25.5^{\circ}$ reflects the (101) diffraction. In comparing their areas of different heat treated samples, the cyclization of both PANs was identified as a first-order reaction. The rate constants of cyclization reaction at different temperatures and the active energy parameter were obtained. This results might provide an important effect on pre-oxidation of polyacrylonitrile fiber.

• Macromolecular Research
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• v.15 no.6
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• pp.565-574
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• 2007

In this study, five representative, commercially available polymers, Ultem 1000 polyetherimide, Kapton polyimide, phenolic resin, polyacrylonitrile and cellulose acetate, were used to prepare pyrolyzed polymer membranes coated on a porous {\alpha}-alumina$ tube via inert pyrolysis for gas separation. Pyrolysis conditions (i.e., final temperature and thermal dwell time) of each polymer were determined using a thermogravimetric method coupled with real-time mass spectroscopy. The surface area and pore size distribution of the pyrolyzed materials derived from the polymers were estimated from the nitrogen adsorption/desorption isotherms. Pyrolyzed membranes from polymer precursors exhibited type I sorption behavior except cellulose acetate (type IV). The gas permeation of the carbon/{\alpha}-alumina$ tubular membranes was characterized using four gases: helium, carbon dioxide, oxygen and nitrogen. The polyetherimide, polyimide, and phenolic resin pyrolyzed polymer membranes showed typical molecular sieving gas permeation behavior, while membranes from polyacrylonitrile and cellulose acetate exhibited intermediate behavior between Knudsen diffusion and molecular sieving. Pyrolyzed membranes with molecular sieving behavior (e.g., polyetherimide, polyimide, and phenolic resin) had a $CO_2/N_2$ selectivity of greater than 15; however, the membranes from polyacrylonitrile and cellulose acetate with intermediate gas transport behavior had a selectivity slightly greater than unity due to their large pore size.