• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.585-587
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• 2004

We report the characterization of white light emitting devices fabricated using conjugated polymer blends. Blue emissive poly[9,9-bis(4'-n-octyloxyphenyl) fluorene-2,7-diyl-co-10-(2'-ethylhexyl)phenothiazine-3,7-diyl] [poly(BOPF-co-PTZ)] and red emissive poly(2-(2'-ethylhexyloxy)-5-methoxy-1,4-phenylenevinylene) (MEH-PPV) were employed in the blends. The inefficient energy transfer between these blue and red light emitting polymers (previously deduced from the PL spectra of the blend films) enables the production of white light emission through control of the blend ratio. The PL and EL emission spectra of the blend systems were found to vary with the blend ratio. The EL devices were fabricated in the ITO/PEDOT/blend/LiF/Al configuration and white light emission was obtained for one of the tested blend ratios.

• 한국안전학회지
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• 제21권1호
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• pp.79-85
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• 2006

Olefinic compatibilized blend(R-PP/R-PE)/layered silicate composites have been prepared by melt intercalation technique directed from $Na^{+}$ montmorillonite(MMT) or organophilic montmorillonites while using magnesium hydroxide as flame retardant. Morphology and flammability properties were characterized by X-ray diffraction(XRD), transmission electron microscopy(TEM), scanning electron microscopy(SEM), thermogravimetry analysis(TGA), limiting oxygen index(LOI), UL94 test. It is found that the compatibilized blend/layered silicate(Cloisite 20A) nanocomposites have a mixed immiscible-intercalated structure and there is better intercalation when a compatibilizer is combined with the polymer and layered silicate to be melt blended. A very large increase in the LOI value was observed with hybrid filler addition and further enhancement in thermal stability and compatibility of blend was obtained for the compatibilized blend containing small amount of layered silicate.

• 한국환경보건학회지
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• 제24권3호
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• pp.48-53
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• 1998

Chitin is known as biodegradable natural polymer. But, in spite of various application of chitin from waste marine sources, commercial use of chitin has been limited due to highly resistance to chemicals and the absense of proper solvents. We made various viscosity of chitosan from chitin by change of Mima's method through the deacetylation which is various condition of NaOH concentration, reaction time and temperature. Also, Polyvinyl alcohol/chitosan blend films were prepared by different solution blends containing the ratio of 5, 10, 15 and 20% chitosan and low, medium, high molecular weight of chitosan to find a more useful biodegradable polymer. Thermal and mechanical properties of PVA/chitosan blend films such as DSC, impact strength, tensile strength and morphological changes by SEM were determined. The 10-15% PVA/chitosan(low, medium) blend films were similar to PVA. Also, PVA/chitosan blend films at the laboratory soil test(Pot Test) were completely degraded in month with four kinds of soils by microorganisms.

• Macromolecular Research
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• 제10권1호
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• pp.44-48
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• 2002

The supermolecular structures of poly(ethylene terephthalate) (PET), poly(ethylene 2,6-naphthalate) (PEN), and their blend were investigated with optical microscopy and small angle light scattering. With increasing the crystallization temperature, incomplete spherulitic texture was developed for the PET samples. At a high crystallization temperature of 220 $^{\circ}C$, the light scattering pattern represented a random collection of uncorrelated lamellae. The general morphological appearances for the PEN samples were similar to that of the PET. A notable feature was that the spherulites of the PEN formed at 200 $^{\circ}C$ showed regular concentric bands arising from a regular twist in the radiating lamellae. The spherulitic morphology of the PET/PEN blend was largely influenced by the changes of the sequence distribution in polymer chains determined by the level of transesterifcation. The increased sequential irregularity in the polymer chains via transesterification caused a morphological transition from a regular folded crystallite to a tilted lamellar crystallite.

• Elastomers and Composites
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• 제56권4호
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• pp.209-216
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• 2021

In this study, we observed the mechanical properties, thermal stability, and low temperature sealing performance of fluorosilicone elastic composites. When the blend ratio of Phenyl vinyl methyl silicone (PVMQ) was increased, the tensile strength, modulus at 100%, and compression set were decreased. The thermal stability of fluorosilicone elastic composites showed a similar tendency. These were caused by poorer green strength of PVMQ than Fluorosilicone rubber (FVMQ). The change in the tensile strength and elongation at -40℃ showed a decreasing tendency with increasing PVMQ blend ratio. By increasing the PVMQ blend ratio, low-temperature performance was improved. The Dynamic mechanical analysis (DMA) results showed that T_g was decreased and low-temperature performance was improved with increasing PVMQ blend ratio. However tanδ was decreased becaused of the poor green strength and elasticity of PVMQ. From a hysteresis loss at -40℃, the hysteresis loss value was increased and fluorosilicone elastic composites showed the decreasing tendency of elasticity with increasing PVMQ blend ratio. From the TR test, TR10 was decreased with increasing PVMQ blend ratio. FS-4 (45% PVMQ blended composites) showed a TR10 of -68.0℃ that was 5℃ lower than that of FS-1 (100% FVMQ). The gas leakage temperature was decreased with increasing PVMQ blend ratio. The gas leakage temperature of FS-4 was -69.2℃ that was 5℃ lower than that of FS-1. Caused by the polymer chain started to transfer from a glassy state to a rubbery state and had a mobility of chain under T_g, the gas leakage temperature showed a lower value than T_g. The sealing performance at low temperature was dominated by T_g that directly affected the mobility of the polymer chain.

• 폴리머
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• 제33권3호
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• pp.248-253
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• 2009

의료용으로 적용될 수 있는 새로운 재료를 제조하기 위하여 폴리카프로락톤(PCL)과 양친성 구조를 갖는 폴리(에틸렌 글리콜)(PEG)이 그래프트된 PCL을 이용하여 생분해성 블렌드를 제조하였다. 제조된 블렌드는 PCL을 기본으로 하고 여기에 그래프트 공중합체의 함량을 변화시키며 열적 그리고 결정화 특성을 관찰하였다. 그래프트 공중합체의 함량 변화에 따라 결정화 온도의 변화 및 결정화 속도가 변화하였고 이를 통해 그래프트 공중합체가 PCL의 결정화 거동에 영향을 미침을 확인하였다. 이는 광학현미경을 통한 결정의 교대 소광 밴드의 관찰을 통하여서도 확인할 수 있었다. 약물방출시스템과 같은 의료용 응용을 고려하여 블렌드 필름의 흡수거동과 단백질 흡착에 대한 특성도 평가하였다.

• Elastomers and Composites
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• 제6권1호
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• pp.71-81
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• 1971

The intention of this study is to investigate the properties of polymer blend, NBR/PVC vulcanizates and blending procedures such as roll-mixing temperatures and sequences for polymer blending of NBR and PVC(resin type). The results obtained are as follows: 1. The roll temperature applied for polymer blending is around $150^{\circ}C$. At this temperature region, the degradation of rubber stock, which may be caused by heat, can be minimized and mill processing in practical application in industries can also be facilitated. 2. It is obviously necessary that a small amount of plasticizers should be added to the stock for improving processibility of roll mixing and physical properties. 3. On roll-mixing sequence, it is more effective that PVC compounded with plasticizer is added to NBR milled on hot roll. 4. The vulcanizates of the blends with different degree of polymerization of PVC ale similar to one another in properties. 5. NBR/PVC(70/30) blends shows the better physical characters than eve,-made foreign latex blend except abrasion-resistance. 6. As PVC addition ratio is increased, the physical properties such as resistance to ozone, tear, heat and oil and tensile strength, modulus, hardness have also improved, on the other hand, tension set and rebound character decreased. 7. The curve of ultimate elongation have point of inflection at the ratio of $30\sim40$ part of PVC. 8. While CR is blended, the physical properties such as brittle point, rebound and resistance to oil in high temperature have improved. 9. Polymer blend of NBR and domestic PVC is applied for the industrial utility such as rubber sole and heel, electric wire cover and oil-resistant packing, coating and gasket, printing roll, film for food packing etc.

• 폴리머
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• 제35권3호
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• pp.249-253
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• 2011

PET/PEN 블렌딩에 의하여 발현되는 형태학적 변화가 PET/PEN 블렌드 유연기관 특성에 미치는 영향을 살펴보았다. PET와 PEN의 용융 블렌딩에 따른 two phase 형태학적 변화는 블렌드의 유연기관으로서의 치수안정성을 증가시킴을 알 수 있었다. PET/PEN 필름의 가공조건에 따른 상호에스테르 교환반응은 블렌드의 two phase 형태와 결정화도를 변화시키며 이러한 거시적 형태학적 변화는 유연기관으로서의 PET/PEN 필름의 치수안정성에 영향을 미침을 확인하였다. 결정화도가 높을수록 상호에스테르 교환반응이 낮을수록 PET/PEN 블렌드 필름의 치수안정성이 우수해짐을 알 수 있었다.

• 한국응용과학기술학회지
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• 제16권1호
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• pp.25-31
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• 1999

Algin is known as biodegradable natural polymer from marine plants. PVA/Algin blend films were prepared by solution blending method for the purpose of useful biodegradable polymer. Characteristics properties of PVA/Algin blend films such as DSC, Elongation, Tensile strength and Morphological change by SEM were determined. Tensile strength and Elongation were rapidly reduced as increasing the blend ratio of Algin. PVA/Algin blend films were found that phase separation was occured as more than 25wt% increasing the blend ratio of Algin. Blend films were observed to be less partially compatibility than 10wt% increasing the blend ratio of Algin by DSC, mechanical properties and SEM. Also, PVA/Algin blend films at the laboratory soil test(Pot Test) were completely degraded in months with four kinds of soils by microorganisms.

• 폴리머
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• 제24권3호
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• pp.366-373
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• 2000

본 연구에서는 poly(phenylene sulfide)(PPS)와 ABS의 물성을 상호보완하기 위하여 블렌드를 제조하였다. 각 성분간의 상용성을 증진시키기 위하여 소량의 무수말레인산을 ABS에 반응시켜 MABS (ABS-g-MAH)를 제조하였으며, PPS/ABS 및 PPS/MABS 블렌드는 이축 혼련 압출기를 이용하여 용융 흔합하였다. 블렌드에서 ABS의 화학적 개질이 블렌드의 모폴로지와 열적 성질에 미치는 영향을 관찰하였다. PPS/MABS 블렌드의 경우, 각 성분간에 강한 인력이 형성되는 것을 광학현미경과 SEM을 이용하여 확인하였으며, DMA 분석에서는 단일 유리전이 온도를 확인하였다. 또한 화학적으로 개질된 MABS를 사용한 PPS/MABS의 블렌드는 PPS/ABS보다 향상된 열적 성질을 나타내었다.