• 폴리머
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• 제25권3호
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• pp.406-413
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• 2001

고분자의 블렌드는 새로운 성질을 가지는 재료의 제조를 위한 하나의 방법으로 제시되고 있다. 그러나 대부분의 재료는 재료사이의 점탄성, 표면에너지 그리고 상호결합력의 차이로 인하여 비상용성을 지니며, 이로 인하여 블렌드물은 예상되는 물성을 나타내지 못하는 경우가 있다. 실리콘 고무는 우수한 내열성과 전기적 성질을 가지며, ethylene propylene diene monomer (EPDM) 고무는 우수한 기계적 물성을 지니고 있다. 본 실험에서는 실리콘과 EPDM 고무의 블렌드를 통한 전기적 성질과 기계적 물성이 우수한 새로운 기능성 재료의 개발에 목적을 두었다.

• Elastomers and Composites
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• 제9권1호
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• pp.5-13
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• 1974

The characteristics of IR and IR blended elastomers, for footwear by means of blending with NR and SBR, have been studied. The results obtained were as follows: 1. The mastication of IR was almost not required, where as NR and SBR are necessary. Therefore mixing time was much reduced because of speedy filler feeding. 2. Disadvantage of low Mooney viscosity was covered by blending with NR and SBR, and by loading filler. Superior flow property in comparison to other polymers was worthy and valuable in providing formulas for mould flow, 3. The elongation property of green stocks and vulcanizates was shown smooth surface for extruded and calendered stocks, and facilitated fabrication processes. 4. Because of slow vulcanization, IR is required to control vulcanization time by adding proper accelerators. This property, in turn, made possible to improve the storing stability of green stocks by controlling scorch time.

• 펄프종이기술
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• 제35권3호
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• pp.13-20
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• 2003

This study was carried out to investigate the effect of surface modified pigments on the properties of coated paper. The selected core particle(clay, talc) and fine particle(TiO$_2$) were modified by hybridization. The optical properties of modified pigments, rheological properties of coating color, and optical properties of coated paper were investigated. It was found that particles formed sphere-like shape and became more uniform during the surface modification in the hybridization system. As a result, It was estimated that surface modification of TiO$_2$ turned out to be more effective in improving optical properties of pigment and coated paper than simply blending it.

• 대한조선학회논문집
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• 제45권6호
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• pp.601-610
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• 2008

This paper deals with a new geometrical surface modeling method of forebody's hull form which is fully defined by form parameters. The complex hull form in the forebody can be modeled by the combination of three parts: bare hull, bulbous bow and blending part which connects a bare hull and a bulbous bow. All these subdomain parts are characterized by each own form parameters and constructed with simple surface model. For this, we need only 2-dimensional hull form data and then the form parameters are calculated automatically from these data. Finally, the smooth hull form surfaces are generated by parametric design and fair-skinning. In the practical point of view, we show that this new method can be useful and efficient modeling tool by applying to the hull form surface modeling of Panamax container's forebody.

• 공업화학
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• 제5권5호
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• pp.819-824
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• 1994

Dimethylformamide를 공통용매로 하여 $H_3PMo_{12}O_{40}$와 polysulfone를 동시에 녹여 분리막 형태의 $H_3PMo_{12}O_{40}$-polysulfone 필름을 제조하였다. SEM 및 EDX 분석 결과 필름 촉매상에서 $H_3PMo_{12}O_{40}$는 매우 고른 상태로 잘 분산되어 있음을 확인되었다. ESCA 분석결과에 의하면 Mo의 산화상태에는 변화가 없었다. 에탄을 전환반응에서 $H_3PMo_{12}O_{40}$-polysulfone 필름 촉매는 $H_3PMo_{12}O_{40}$보다 낮은 산반응특성과 높은 산화반응 특성을 보였으며, 산화반응의 활성은 약 10배 정도 크게 나타났다. 산 특성의 감소는 $H_3PMo_{12}O_{40}$의 산점과 강하게 결합된 dimethylformamide에 기인하여, 산화특성의 증가는 촉매의 고른 분산에 기인하였다. 흡착실험 결과 블랜딩 후 $H_3PMo_{12}O_{40}$의 표면 특성은 크게 증가하였으나 내부 특성은 큰 변화가 없는 것으로 나타났다. 따라서 헤테로폴리산을 고분자와 블랜딩시킬 경우 헤테로폴리산이 지니는 산 및 산화환원 특성의 제어는 물론 촉매의 표면 및 내부 특성 제어가 가능할 것으로 여겨진다.

• 한국식품영양과학회지
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• 제35권8호
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• pp.1051-1056
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• 2006

온도와 ATP 증가에 따라 사과.당근 배합비율과 상관없이 혼합주스의 투과플럭스가 비례적으로 증가했으며, 특히 온도변화에 따른 투과플럭스의 증가가 뚜렷했다. 사과와 당근비가 3:1인 실험구에서 가용성 고형분과 총당의 함량이 높게 측정되었고, 가용성 고형분의 경우 시료배합비율의 영향이, 총당의 경우 온도의 영향이 큰 것으로 나타났다. 시료배합비율에 따른 비타민 C 함량차이는 크지 않았으나 당근의 함량이 많을수록 비타민 C의 함량이 높게 측정되었고, 압력증가에 따른 비타민 C 함량 증가가 뚜렷했다. 사과의 함량이 높을수록 산도도 높았고, 온도증가에 따른 산도의 증가도 뚜렷했다. 한외여과 결과, 전 시료에 걸쳐 우수한 청징효과를 나타내었고, 사과와 당근비가 3:1인 실험구에서 그 청징효과가 두드러졌으며, 또한 점도변화도 가장 컸다. 또한 공정최적화 결과 공정온도 및 ATP가 각각 $44.97^{\circ}C$, 113.57 kPa이고 사과의 혼합비율이 28.50%인 경우 $flux=0.216\;L/m^2.h$, soluble $solids=10.39^{\circ}Brix$, total sugar=71.32 mg/mL, vitamin C=315.18 mg%, acidity=7.78 mL, turbidity=0.017, viscosity=1.44 cp인 사과.당근 혼합과채주스를 제조할 수 있는 것으로 나타났다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.6-8
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• 2001

This report describes the effect of the blending of poly(trifluoropropylmethylvinylsiloxane) (PTFPMVS) with poly(dimethylsiloxane) (PDMS) on the surface properties such as water repellency using dynamic contact angle (DCA) measurement. We have investigated the surface molecular mobility of the PDMS/PTFPMVS blends via a DCA measurement and an adhesion tension relaxation. It could be shown that a flexible side-chain segment in PTFPMVS having higher surface energy, could be reoriented easily in water to decrease the interfacial tension of the polymer/water interface, which seems to play a major role at the decrease of the receding contact angle and the surface resistivity of PDMS/PTFPMVS blends.

• Elastomers and Composites
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• 제52권1호
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• pp.81-85
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• 2017

In order to improve the water resistance, we synthesized waterborne polyurethane by using polyester polyol, poly(propylene carbonate) (PPC), 4,4'-dicyclohexylmethane diisocyanate ($H_{12}MDI$), and dimethylolpropionic acid (DMPA). The properties of the synthesized waterborne polyurethane using poly(propylene carbonate) (WPUP) were evaluated by FT-IR, $^1H-NMR$, GPC, DSC, TGA, and UTM. The mechanical properties increased while the adhesion properties decreased with the increase in the amount of PPC. The highest water resistance was shown when the ratio of polyester polyol to PPC was 9:1.

• 펄프종이기술
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• 제44권3호
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• pp.1-8
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• 2012

The effects of several factors including organic pigment blending and calending conditions on the surface and optical properties of coated paper were investigated. When clay and calcium carbonate are blended in the ratio of 7 to 3, highest smoothness and relative sediment volume were obtained. When organic pigments were added to the mixture of clay and calcium carbonate, the relative sediment volume did not changed significantly. However, when organic pigments were added to calcium carbonate, sheet gloss and smoothness were improved, and showed the better results than that obtained from the mixture of organic pigment and clay. When organic pigment is blended with clay, the particles of organic pigment are buried in the packing structure of coating layer. However, the particle shape of calcium carbonate is quite different from that of clay, and the aspect ratio of calcium carbonate is similar to that of organic pigment. Thus organic pigment particles are not buried and improved effectively the physical characteristics of coating layer. When the hollow sphere pigment was blended, opacity and sheet gloss were improved significantly. Even though the coating color applied was reduced, the similar level of opacity was maintained. Also, if particle size and void volume are increased, gloss is improved, because coating layer is easily transformed in calendering. Therefore, even though lower pressure was applied during calendering, the smoothness of surface of coating layer was improved, and the decrease of void volume in coating layer was reduced, and the quality of coated sheet can be improved.

• 청정기술
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• 제15권3호
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• pp.180-185
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• 2009

자동차용 웨더스트립 제조공정 중 발생하는 에틸렌-프로필렌 고무 스크랩을 고온전단분쇄기를 이용하여 표면활성화 된 분말을 얻은 후 이를 폴리프로필렌과 블렌드하여 열가소성탄성체를 제조하기 위한 기초연구를 수행하였다. 에틸렌-프로필렌 고무 스크랩 분쇄 시 표면활성제를 1.5 phr 첨가하면 최적의 표면활성화 된 분말을 얻을 수 있었다. 폴리프로필렌의 경우는 maleic anhydride를 반응블렌드에 의해 그라프트시켜 기능화 하였다. 기능화된 에틸렌-프로펄렌 분말과 폴리프로필렌을 블렌드하여 열가소성탄성체를 제조할 때 계면젖음 특성이 중요하기 때문에 계면젖음성을 향상시키기 위하여 상용화제로 poly(ethylene-co-acrylic arid)를 폴리프로필렌에 첨가하였다. Poly(ethylene-co-acrylic acid)는 폴리프로필렌의 표면장력을 감소시켰으며 이로 인해 에틸렌-프로필렌 분말과의 계면젖음성이 크게 증진될 것으로 기대된다.