• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2011년도 춘계학술논문집 1부
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• pp.332-335
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• 2011

원적외선, 음이온 방출과 항균, 탈취, 난연등의 효과를 가지는 황토를 합성수지와 혼합하여 복합소재를 연구하여 환경 친화적인 특징과 원적외선, 음이온의 방출을 이룰 수 있는 복합소재 조성을 연구하였다. PP는 MI가 2~60이고, TPE로 Ethylene계을 사용하였으며, 황토와 PP의 혼련을 도와주기 위하여 MA-g-PP를 첨가하였고, 활제, 분산제 및 산화방지제를 첨가하여 compounding 하였다. 또한 황토의 종류에따라 적황토, 호황토, 홍토, 백토, 흑토등으로 구분되고, 각각의 황토 마다 다양한 종류의 입도를 가지고 있으며, 또한 환경 친화적이며 난연성을 부여하기 위하여 다양한 조성으로 compounding 하였다, 황토의 종류에 따른 복합재료의 물성으로부터 기계적 특성치, 원적외선 방사율, 난연성등을 확인하고, 친환경 난연 복합소재 기술을 연구하였다. 적황토의 경우 황토의 함량이 많을수록 인장강도는 작아지는 경향을 나타냈으며, 입도가 작을수록 인장강도가 커지는 경향을 나타냈다. 파단신율의 경우 적황토(#2000)에서 가장 양호하게 나타났으며, 굴곡강도, 충격강도의 경우 적황토(#5000)에서 MI 의 경우 적황토(#325)에서 양호하게 나타났다.

• 반도체디스플레이기술학회지
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• 제11권1호
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• pp.21-27
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• 2012

The optical diffuser for direct-lit LED backlight unit was prepared by using extrusion compounding followed by thermoforming process. Poly(methyl methacrylate) (PMMA) with superior optical characteristics and polycarbonate (PC) with good thermal property were used as base resins, and crosslinked polystyrene (PS) and PMMA beads as diffusing agents were incorporated into resin matrix to derive light scattering and diffusing action. In the compounded plate, the diffusing beads were observed to be dispersed uniformly and distinctly in the continuous phase. The inclusion of polymeric beads up to 3 wt% substantially enhanced the optical characteristics such as luminance, luminance uniformity, haze for the diffuser. Two different diffusers of PC and PMMA-based compound with various compositions were compared in terms of measured optical, thermal, and mechanical properties, which would be expected to be utilized for the industrial application of LED backlight unit.

• 대한의용생체공학회:의공학회지
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• 제30권3호
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• pp.233-240
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• 2009

Using a spatial compound imaging technique in a medical ultrasound imaging system, the average speed of sound in a medium of interest is measured, and imaging of its distribution is implemented. When the brightness reaches the highest level in an ultrasonic image obtained as the speed of sound used in focusing is varied, it turns out that the focusing has been accomplished satisfactorily and that the speed of sound which has been adopted becomes the sought-after average speed of sound. Because spatial compound imaging provides many different views of the same object, the adverse effect of erroneous speed-of-sound estimation tends to be more severe in compound imaging than in plain B-mode imaging. Thus, in compound imaging, the average speed of sound even in the case of speckled images can be accurately estimated by observing the brightness change due to different speeds of sound employed. Using this new method that offers spatial diversity, we can construct an image of the speed of sound distribution in a phantom embedded with a 10-mm diameter plastic cylinder whose speed of sound is different from that of the background. The speed of sound in the cylinder is found to be different from that of the surrounding medium.

• 한국응용과학기술학회지
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• 제20권2호
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• pp.165-172
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• 2003

Fireproofing polyolefin nanocomposite for the application of power distributing panel was prepared by compounding linear low density polyethylene(LLDPE), decabromodiphenyl oxide (DBDPO), $Sb_2O_3$ as flame retardant agents, and modified nano clay as filler. The optimized formulation ratio of compounds to prepare the fireproofing polyolefin nanocomposite was obtained. The flame retardant properties for nanocomposite prepared by compounding 22.5 phr of nano clay and 18 phr of DBDPO based on 100 phr of LLDPE were shown that the combustion time. 10${\sim}$18 s, combustion distance, 12${\sim}$15 mm and non-melt dropping characteristics. In particular. the content of DBDPO in nanocomposite could be decreased to 18 phr from 40 phr DBDPO for fireproofing composite containing 30 phr of clay. The electrical properties measured from tracking test, had an excellent antitracking properties by not showing the phenomenon of leakage current and sparking.

• Elastomers and Composites
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• 제38권2호
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• pp.122-127
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• 2003

환경에 유해한 PVC 재질의 바닥재나 시트를 대체하기 위하여 styrene-ethylene-butadiene-styrene(SEBS)과 같은 열가소성고무를 사용하고 polypropylene(PP) 등의 폴리머와 오일, 무기물 및 안정제 등을 혼합하여 내충격성 또는 탄성이 우수한 새로운 소재를 개발하기 위한 컴파운딩 연구를 진행하였다. SEBS와 오일의 혼합물에서 경도는 오일의 함량이 증가함에 따라서 선형적으로 감소하였고, SEBS/oil/PP의 조성물에서는 PP의 함량이 증가하면 인장강도는 선형적으로 증가하는 반면, 신율은 PP가 50phr상에서는 거의 영향이 없었다. PVC 소재의 바닥재나 시트를 대체 사용하기 위한 실질적인 SEBS 혼합물의 조성물에서도 인장 및 인열강도, 그리고 경도는 PP 함량에 비례하여 증가하는 것으로 나타났으나, 용융지수는 PP 함량이 증가하면 감소하는 것으로 나타났다.

• Elastomers and Composites
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• 제33권3호
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• pp.201-209
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• 1998

고무배합물의 충진제로 사용되는 알루미나 분말의 제조에 있어서 재래식 및 마이크로파 에너지원에 의하여 황산용액중의 카올린으로 부터 알루미나를 얻는다. 이때 카올린으로부터 알루미나 분말의 최대 추출율은 각각 재래식의 경우는 $80^{\circ}C$, 1M 황산, 180분에서 72.8%이고, 마이크로파 추출 공정의 경우는 $90^{\circ}C$, 1m 황산, 60분에서 $99\%$였다. 또한 추출된 시료는 TG/DTA, XRD, SEM, Atomic Emission Spectroscopy 및 BET법에 의하여 분석하였다..

• Elastomers and Composites
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• 제44권3호
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• pp.260-268
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• 2009

Clay의 표면을 bis[(3-triethoxysilylpropyl)tetra sulfide (TSS)으로 처리하면 clay 표면의 소수성이 증가 될 뿐만 아니라 high temperature vulcanization 형 silicone rubber(HTV)와 화학적 반응이 가능하기 때문에 clay와 silicone rubber 사이의 상용성이 향상될 수 있을 것으로 예상되어 TSS를 이용하여 Na-MMT와 Fe-MMT의 silicate 층 표면에 tetra sulfide 그룹을 도입시킨 Na-$MMTS_4$와 Fe-$MMTS_4$를 각각 제작하였다. 이들 clay를 HTV silicone rubber와 compounding하여 silicone rubber/clay composites를 제작하였으며, clay의 종류 및 표면개질에 따른 silicone rubber 복합체의 열적안정성 및 기계적 물성을 평가하였다.

• Macromolecular Research
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• 제12권3호
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• pp.293-302
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• 2004

We added surface-modified silica nanoparticles to poly(ethylene 2,6-naphthalate) (PEN) to investigate their effect on the mechanical properties on the PEN nanocomposite material. The torque and total torque values of the composites decreased in the silica nanoparticle composites. The tensile modulus of the composites reinforced with unmodified silica nanoparticles increased upon increasing the silica content, while the tensile strength and elongation decreased accordingly. In contrast, stearic acid-modified, silica nanoparticle reinforced PEN composites exhibited an increase in elongation and a decrease in tensile modulus upon addition of the silica nanoparticles because the stearic acid that had adsorbed onto the surface of the silica nanoparticle in multilayers could act as a plasticizer during melt compounding. Stearic acid modification had a small effect on the crystallization behavior of the composites. We calculated theoretical values of the tensile modulus using the Einstein, Kerner, and Nielsen equations and compared these values with the experimental data obtained from the composites. The parameters calculated using the Nielsen equation and the Nicolais- Narkis model revealed that the interfacial adhesion between silica nanoparticles and the PEN matrix could be improved.

• 한국식생활문화학회지
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• 제19권2호
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• pp.193-199
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• 2004

The purpose of this study was to determine the organoleptic charateristics of cauliflower pickles made in various compounding ratio according to central conposite design for optimum organoleptic characteristics of the cauliflower pickles. The optimum mixing condition of cauliflower pickles were optimized, using central composite design with 3 variables and 3 levels, by response surface methodology. The various kinds of cauliflower pickle were made in various compounding ratio of vinegar, salt and sucrose - critical ingredients of pickle recipe - and were presented to reliable panels, who graded the subjects in 7 degrees for 4 items : color, flavor, hardness and overall quality. The optimum mixing conditions of cauliflower pickle were 603.50g of vinegar, 80.13g of salt and 251.07g of sucrose in the maximum point of overall quality.

• Elastomers and Composites
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• 제54권3호
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• pp.220-224
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• 2019

Herein, three polymer compounds were manufactured using three polymer combination methods, ethylene-vinyl acetate/ethylene-propylene-diene-copolymer (EPDM), ethylene-vinyl acetate (EVA)/polyethylene-A (PE-A; density: 0.870), and ethylene-vinyl acetate (EVA)/polyethylene-B (PE-B; density: 0.885), for making cable sheath for use in the shipping industry. In this study, EVA, EPDM, PE-A, and PE-B were used as matrix polymers, and EVA-grafted maleic anhydride was used as a coupling agent for compounding with various compounds such as a fire retardant, cross-linking agent, filler, and other additives, besides the plasticizer. ${\Delta}T$, Mooney viscosity, and tensile strength increased in order of EPDM < PE-A < PE-B, the probable reason is due to the different crosslinking effect. The three compounds showed similar results for fire resistance and aging resistance after compounding process, but they showed excellent cold resistance owing to the non-polarity of the polymers and sufficient plasticizer content.