• 자원리싸이클링
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• 제13권5호
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• pp.23-27
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• 2004

플라스틱 중에서 열가소성 수지는 재활용이 가능하지만 재활용 수지에 대한 균일한 물성의 신뢰성이 부족하기 때문에 제한적으로 사용되고 잇다. 정확한 재활용의 정도에 따른 물성을 파악하여 사용 범위를 규정하는 것은 제한된 자원을 효율적으로 사용할 수 있는 중요한 방법이라 하겠다. 본 연구는 고밀도 폴리 에틸렌(HDPE)을 대상으로 재활용의 정도에 따른 물성의 변화를 실험적으로 수행하였다. 재활용을 하지 않은 수지와 재활용 수지를 중량비를 기준으로 혼합하여 실험을 수행하였으며 기계적인 물성의 변화를 측정하였다.

• 한국기계가공학회지
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• 제14권2호
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• pp.87-92
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• 2015

The injection molding process is widely used in the production of most plastic products. In order to make metal-colored plastic products like those found in modern luxury home alliances, metallic pigments are mixed with a basic resin material for injection molding. However, process control for metal-colored plastic products is extremely difficult due to the non-uniform melt flow of the metallic resin pigments. In this study, the effect of process parameters on the quality of a metal-colored plastic product is evaluated. A rapid mold cooling method using a compressed cryogenic fluid is also proposed to decrease the content of undesired compounds within the plastic product.

• Journal of the Korean Wood Science and Technology
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• 제37권3호
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• pp.216-221
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• 2009

인피섬유로 한지를 제조하고 남은 닥나무 목질부를 활용하기위한 방안으로 닥나무 목질부 파티클을 이용하여 보드를 제조하고 밀도 및 수지첨가량에 따른 물성을 검토하였다. 흡수율은 보드의 밀도 및 수지첨가량이 증가할수록 감소하였으며, 휨강도 및 Brinell 경도는 밀도 및 수지첨가량이 증가할수록 세포간 결합력이 커져 증가하였다. 흡수 두께 팽창율은 보드의 밀도가 증가함에 따라 증가하였고, 수지첨가량이 증가할수록 감소하였다.

• Elastomers and Composites
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• 제29권5호
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• pp.436-443
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• 1994

Melamine resin was mixed with polybutadiene rubber or wood flour in the ranges of $5{\sim}75%(wt.%)$. For mixtures, physical and thermal properties were tested experimentally. Physical properties were mainly influenced on the dispersed states of rubber or wood flour. The highest flexural and impact strength were obtained at wood flour content $65{\times}67%$. Rubber was homopolymerized by hardner, or partially copolymerized with melamine resin. At rubber content $3{\sim}6%$, cured products represented lower modulus without decreasing mechanical strength.

• Elastomers and Composites
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• 제32권1호
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• pp.11-19
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• 1997

[ ${\gamm}-Glycidoxy$ ] propyl trimethoxy silane, CTBN rubber(carboxyl terminated butadiene acrylonitrile rubber) and GMA(glycidyl methacrylate) were reacted on the surface of silica one by one in existence of TEA(triethylamine) or BPO(benzoyl peroxide). The amount of reactant was $2.5{\sim}5.8%$ of treated silica weight. The treated silica was mixed with epoxy resin and MTHPA(methyl tetrahydro phthalic anhydride) in the range of $0{\sim}60%$(wt.%) of total component. The thermal properties were tested for cured products. By using silica treated with silane/rubber or silane/rubber/vinyl, comparing with 3% of rubber mixed directly, it had 13% higher $T_g$ and 10% lower thermal expansion coefficient at $35{\sim}55%$ of silica contents.

• 한국전기전자재료학회논문지
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• 제26권9호
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• pp.656-661
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• 2013

In this study, the moisture content, charge discharge current, electrostatic capacity and dielectric loss tangent are measured for the specimen of bisphenol type epoxy resin which is mixed with squared amorphous silica filler and dipped in hot water of $50^{\circ}C$ for 169 days. The results of this study are listed below. The longer of deposition day, the charge and discharge current was increased. It is considered that the reason is because there was water attack through the squared silica surface. The longer of deposition day, the absorption rate of all specimens was increased. It found that the absorption rate reached saturated state after 100 days. The higher frequency and the longer of deposition day, the $tan{\delta}$ was decreased. Also, It found that the $tan{\delta}$ and electrostatic capacity of the specimen which is mixed with squared filler are greater.

• 한국전기전자재료학회논문지
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• 제21권2호
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• pp.188-193
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• 2008

Epoxy/Organically Modified Layered Silicate Nanocomposites were prepared by dispersing synthetic layered silicate modified with alkyl ammonium ions. In the dispersing process, the organically modified layered silicate were mixed in epoxy resin with shearing, and aggregation of the silicate were removed by centrifugal separation after mixing epoxy resin and silicates. Micrographs taken by transmission electron microscopy(TEM) indicate that the nanocomposites have a mixed morphology including both parallel silicate layers and exfoliated silicate layers area, As the thermal properties, the glass transition temperature of the nanocomposites was shifted to a higher temperature($+6^{\circ}C$)than pure epoxy. Furthermore, dispersion of OMLS will prevented relative permittivity from increasing at a high temperature above the glass transition temperature.

• Restorative Dentistry and Endodontics
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• 제4권1호
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• pp.29-34
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• 1978

The purpose of this study was to measure penetration of dye stuff(5% Methylene blue, Hematoxylin, Crystal violet and Safranin-O) on silicate cement, Adaptic, Hi-pol and unfilled resin. Each filling material was mixed on the mixing pad and the mixed material was inserted with condensation force of 500gr, 1000gr and 2000gr and without condensation force into preformed glass tube (10mm in diameter and 10mm in height). The specimen was stored in the air for 24 hours, then specimen was immersed in various dye solution (5% methylene blue, hematoxin, crystal violet and safranin-O) for different period of time (l hour and 24 hours). These dye-treated specimen was cut horizontally at the middle portion and the dye penetration in cut surface was measured. Following results were obtained. 1. Pentration of various dye was excessive in silicate cement with and without Condensation force. 2. There has been no evidence of dye penetration in unfilled resin. 3. Dye penetration occurced with in 1 hour period and the extending time didn't affect the dye penetration.

• Bulletin of the Korean Chemical Society
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• 제1권2호
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• pp.49-54
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• 1980

Solutions of $Ni^{2+}$ and $Cd^{2+}$ were mixed with the solutions of various dibasic organic acids in the presence of cation exchange resin at room temperature. The distribution ratios of the metal ions between resin and solution were measured, using radioactive metal ions as tracer. From the observed variation of the distribution ratios with acid anion concentrations, it was concluded that $Ni^{2+}$ and $Cd^{2+}$ formed one-to-one complexes with succinate, malonate, o-phthalate and tartarate ions in aqueous, 20 % ethanol-water and 20 % acetone-water solutions. The results of the present study indicated that the relative stabilities of the complexes in solution increased generally in the order : $Ni^{2+}$ < $Cd^{2+}$ complexes. Succinate < malonate < o-phthalate < tartarate complexes. Aqueous < mixed solvent systems.

• Bulletin of the Korean Chemical Society
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• 제1권3호
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• pp.78-82
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• 1980

Solutions of $Cd^{2+}$, $Co^{2+}$ and $Ni^{2+}$ were mixed with the solutions of hydroxycarboxylic acids such as salicylic, lactic and mandelic acids in the presence of cation exchange resin at room temperature. The distribution ratios of the metal ions between resin and solution were measured, using radioactive metal ions as tracer. From the observed variation of the distribution ratios with the acid anion concentrations, it was concluded that $Cd^{2+}$, $Co^{2+}$ and $Ni^{2+}$ formed the one-to-one complexes with salicylate, lactate and mandelate ions in aqueous, 20 % ethanol-water and 20 % acetone-water solutions. The results of the present study indicated that the relative stabilities of the metal-acid complexes in solution increased in the order: $Cd^{2+}$ <$Co^{2+}$ <$Ni^{2+}$ complexes. Salicylate