• Journal of Korea Technical Association of The Pulp and Paper Industry
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• 제40권1호
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• pp.23-28
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• 2008

Functional hanji was manufactured using the bast fiber of Broussonetia kazinoki and various inorganic compounds such as kaolin, talc, elvan, and ocher, and the physical and optical properties were investigated. The residual percentages of kaolin, talc, elvan and ocher in the functional hanji were above 50%. The density of the hanji increased with the increase of the content of inorganic compounds. The hanji manufactured using ocher showed the highest density. The breaking length and burst factor decreased with the increase of inorganic materials, indicating that physical properties of hanji were not improved by adding inorganic materials. The emission rates of far-infrared radiation increased in the hanji manufactured using inorganic materials. The higher emission rates were observed in the hanji with elvan or ocher. Addition of inorganic compounds to hanji showed the flame retardative effect. The colorfastness to light of the hanji with elvan or ocher was the degree of 4, which explained by the characteristic color of the inorganics.

• Polymer Science and Technology
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• 제8권2호
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• pp.131-138
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• 1997

• Journal of the Korean Ceramic Society
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• 제47권5호
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• pp.381-386
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• 2010

Some basic properties of inorganic coatings hardened by the room temperature reaction with alkalies were examined. The coating paste was prepared from the powders in the system $Al_2O_3-SiO_2$-CaO using blast furnace slag, fly ash and amorphous ceramic fiber after mixing with a solution of sodium hydroxide and water glass. The mineralogical and morphological examinations were performed for the coatings prepared at room temperature and after heating to $1200^{\circ}C$ respectively. The binding force of the coating hardened at room temperature was caused by the formation of fairly dense matrix mainly composed of oyelite-containing amorphous phase formed by the reaction between blast furnace slag and alkali solution. At the temperature, fly ash and ceramic fiber was not reacted but imbedded in the binding phase, giving the fluidity to the paste and reinforcing the coating respectively. During heating up to $1200^{\circ}C$, instead of a break in the coating, anorthite and gehlenite was crystallized out by the reaction among the binding phase and unreacted components in ternary system. The crystallization of these minerals revealed to be a reason that the coating maintains dense morphology after heating. The maintenance of binding force after heat treatment is seemed to be also caused by the formation of welldispersed fiber-like mineral phase which is originated from the shape of the amorphous ceramic fiber used as a raw materials.

• Textile Coloration and Finishing
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• 제33권4호
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• pp.309-316
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• 2021

Due to the rigid nature of the silicon carbide fiber(SiC), fiber damage occurs from the friction during the carding process. This damage not only lowers the spun yarn yield, but also lowers the heat resistance of the spun yarn, so that ultra-high heat resistant yarn cannot be manufactured. Therefore, in the carding process where the most friction between fiber and machine(wire, etc.) occurs, some factors were modified and tested, and as a result of measuring the change in physical properties, fiber damage decreased due to the wire angle or wire density, resulting in improved yield. The test method used to measure the yield of SiC fiber was the carbonization method, and the content of SiC fibers was calculated using the remaining amount after carbonization. Carbonization test was performed at air condition, 700℃, and for 2 hours. Analysis by SEM-EDX showed that the carbide was consistent with the composition of the SiC fiber.

• Macromolecular Research
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• 제16권7호
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• pp.626-630
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• 2008

Poly(vinyl pyrrolidone) was used successfully to control the size and distribution of silver nanoparticles generated on inorganic silica nanofibers. The inorganic nanofibers were electro spun using sol-gel chemistry of silicates, and the diameter of the prepared nanofibers was unaffected by adding up to 7% of poly(vinyl pyrrolidone). The silver ions, in the form of silver nitrate, were introduced into the silica nanofibers and reduced to metallic silver by ultraviolet irradiation with a subsequent thermal treatment. The size of the generated silver particles was decreased dramatically by adding poly(vinyl pyrrolidone). The size of the silver nanoparticles was 73 nm when no poly(vinyl pyrrolidone) was added but 23 nm with the addition of only 1% of poly(vinyl pyrrolidone). The extent of reduction could be checked by determining the concentration of silver ions leached into water from the silica nanofibers. After thermal treatment of the silica nanofibers, more than 99% of the silver remained in the nanofibers, indicating almost complete reduction of the silver ions to silver metal.

• Membrane Journal
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• 제14권1호
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• pp.53-56
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• 2004

Direct Methanol Fuel Cell (DMFC) is considered as a candidate technology for applications in stationary, transportation as well as electronic power generation purposes. To develop a high performance direct methanol fuel cell(DMFC), a competent electrolyte membrane is needed. The electrolyte membrane should be durable and methanol crossover must be low. One of the approaches to increase the stability of generally used polymer electrolyte membranes such as Nafion against swelling or thermal degradation is to bond it with an inorganic material physically or chemically. In Noritake Company, we have developed a novel method of reinforcing the polymer electrolyte matrix with inorganic fibers. Methanol crossover values measured were significantly lower than the original polymer electrolyte membranes. These fiber reinforced electrolyte membranes (FREM) were used for DMFC study and stable power output values as high 160 mW/$\textrm{cm}^2$ were measured. The details of the characteristics of the membranes as well as I-V data of fuel cell stacks are detailed in the paper.

• Proceedings of the KSR Conference
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• 한국철도학회 2006년도 춘계학술대회 논문집
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• pp.630-635
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• 2006

• Macromolecular Research
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• 제14권2호
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• pp.146-154
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• 2006

Organic and inorganic hybrid nanocomposites based on poly(ethylene 2,6-naphthalate) (PEN) and silica nanoparticles were prepared by a melt blending process. In particular, polymer nanocomposites consisting mostly of cheap conventional polyesters with very small quantities of inorganic nanoparticles are of great interest from an industrial perspective. The crystallization behavior of PEN/silica hybrid nanocomposites depended significantly on silica content and crystallization temperature. The activation energy of crystallization for PEN/silica hybrid nanocomposites was decreased by incorporating a small quantity of silica nanoparticles. Double melting behavior was observed in PEN/silica hybrid nanocomposites, and the equilibrium melting temperature decreased with increasing silica content. The fold surface free energy of PEN/silica hybrid nanocomposites decreased with increasing silica content. The work of chain folding (q) for PEN was estimated as $7.28{\times}10^{-20}J$ per molecular chain fold, while the q values for the PEN/silica 0.9 hybrid nanocomposite was $3.71{\times}10^{-20}J$, implying that the incorporation of silica nanoparticles lowers the work required to fold the polymer chains.

• 한국문화재보존과학회:학술대회논문집
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• 한국문화재보존과학회 2004년도 제20회 발표논문집
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• pp.109-114
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• 2004

The purpose of this study lies in analyzing the characteristics of the carbonized textile fabrics and to know the carbonizing mechanism. Samples were Jiyo excavated from the grave of Mrs. Hansan Lee as the wife of Jinju Kang at Daeduk-gu, Daejon, and black fragements assumed as of the outside material of cotton skirt and black dusts collected out of Jikryung for official dress. The composition and status of the fiber were clarified by means of Microscopic FT-IR and both cross sectioanl and side parts of the fiber were observed using the technique of scanning electron microscopy(SEM). Finally EDS analysis was carried out to qualitatively analyze inorganic ingredients contained in the carbonized fiber. As a result of FT-IR measurement, characteristic peak was very strong around $1625cm^{-1}$ and could be found even between 2500 and $2300cm^{-1}$ because of a high-molecule pigmental substance, melanine. When SEM photography was applied to the fractions, the tissues were identified as silk fiborine through the observation of their side and cross sectional parts. SEM-EDS measurement indicated that both the cotton skirt and Jikryung for official dress contained a high proportion of inorganic substances such as Si, Ca suggesting the existence of silicide and calcium carbonate.

• Proceedings of the Korean Fiber Society Conference
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• 한국섬유공학회 2003년도 봄 학술발표회 논문집
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• pp.52-55
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• 2003

Poly (ethylene 2, 6-naphthalate) (PEN) has been used for a high performance engineering plastics such as fiber, film, and packaging, because of excellent physical properties and outstanding gas barrier characteristics [1-2]. However, the application of PEN is limited because PEN exhibits a relatively high melt viscosity. Recently, many researches for organic/inorganic composites by applying nano-particles to the polymer matrix have been carried out [3], and the nano-particles exhibited greatly improved mechanical and rheological properties [4]. (omitted)