• Fibers and Polymers
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• v.7 no.4
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• pp.367-371
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• 2006

Thermal properties of copolyetherester/silica nanocomposites were examined by using DSC and TGA. The segmented block copolyetheresters with various hard segment structures and hard segment contents (HSC) were synthesized and their silica nanocomposite films were prepared by solution casting method. The nano-sized fumed silica particles were found to act as a nucleating agent of the copolyetheresters. The nanocomposites always showed reduced degree of supercooling or faster crystallization than the corresponding copolyetheresters. The nanocomposites also showed increased hard segment crystallinity except HSC 35 sample which had short hard segment length. In case of 2GT [poly(ethylene terephthalate)] copolyetheresters, which were not developed commercially because of their low crystallization rate, the hard segment crystallinity increased considerably. The copolyetherester/silica nanocomposites showed better thermal stability than copolyetheresters.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.75-78
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• 2003

자동차용 타이어는 고무와 고무의 보강 및 치수 안정용으로 사용되는 다량의 타이어코드로 이루어져 있다. 고무는 신축성이 크고 공기압 등에 의해 물성이 현저하게 저하하므로 신축을 적게 하고 물성의 저하를 막기 위해 보강용으로 사용되는 타이어코드는 타이어의 성능과 수명을 좌우하는 중요 요소가 된다[1]. 타이어코드용 PET섬유는 타이어 내에서 계속적인 신장, 굽힘 및 압축변형 등의 물리적 피로를 받고 있기 때문에 이들로 인하여 내피로성이 아주 중요한 의미를 가진다. 이러한 타이어코드용 섬유의 내피로성에 가장 큰 영향을 미치는 것은 섬유의 미세구조인데 주로 결정영역보다는 비결정영역의 구조이고, 피로를 가했을 때 크랙의 성장으로 인해 내피로성이 감소하며 파단이 일어난다. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.372-375
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• 2002

타이어코드는 복합재료의 원조라고도 불리는 타이어의 적절한 보강용 재료로 복합재료용 섬유의 선구자라고 할 수 있다. 1888년 Du Pont에서 공기를 넣는 타이어를 만든 이후 타이어코드는 마, 면, 레이온, 나일론, 스틸, 폴리에스테르, 글라스, 아라미드 등과 같은 새로운 소재가 계속적으로 개발되어 타이어의 고기능화와 함께 타이어코드의 고기능화도 이루어져 왔다[1]. 이러한 타이어 코드 소재로는 현재 여러 가지가 있으나, High Modulus Low Shrinkage (HMLS) 타입의 PET 타이어코드는 다른 소재에 비해 가격이 안정적이고, 강도가 탄성률이 우수하며 특희 나일론에 비하여 초기 탄성계수 및 치수 안정성이 우수하여 평탄점(flot spot)현상도 적기 때문에 레이온을 대신하여 승합차용으로 사용량이 계속 증가되고 있다[2]. (중략)

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.277-280
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• 2002

유,무기 입자가 첨가된 고분자 복합 소재는 고분자 매트릭스에 기계적, 열적 특성을 향상시킬 뿐만 아니라 이들의 다양한 기능성을 부여할 수 있다[1]. 특히 첨가되는 유,무기 입자가 나노 크기로 감소할 경우 단위무게 당 표면적이 증가하므로 이들의 효과가 더욱 현저히 나타나는 장점이 있으며 그 밖에 고유한 광학적, 전기적 특성을 나타내게 된다[2-4]. 그러나 나노 입자간의 강한 표면 작용력으로 인해 균일한 분산상을 얻기 힘든 단점[5]이 있어 최근 이를 개선하기 위한 연구가 활발히 진행되고 있다. (중략)

• Textile Coloration and Finishing
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• v.15 no.4
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• pp.1-7
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• 2003

We investigated the effect of color depth on polyester fabrics by plasma treatment. In this study, although it have many paper about effects of plasma treatment, we observed interfacial electrokinetic potential of polyester fabrics by plasma treatment and also we investigated relationship between deep coloring agent and plasma treatment to get the effect of color depth on polyester fabrics. The results obtained are as follows, 1. Plasma treatment did not enhanced the effect of color depth of polyester fabrics by plasma treatment independently. 2. In the case of using the deep coloring agent with plasma treatment on polyester fabrics, lightness was more decreased than using the deep coloring agent itself. 3. Plasma treatment could not affect surface shape and tensile strength of treated polyester fabrics.

• Textile Coloration and Finishing
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• v.8 no.2
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• pp.56-63
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• 1996

Low-temperature plasma treatment or sputter etching is of interest as one of the techniques to modify polymer surface. In this study, poly(ethylene terephthalate)(PET), nylon 6 and cotton fabrics dyed three black dyes were subjected to low-temperature argon plasma and also sputter etching. In relation to bathochromic effect, the surface characteristics of the treated fabrics and films were investigated by means of critical surface tension, SEM and ESCA measurement. The depth of shade of fabrics more increased by the sputter etching technique than argon plasma treatment. Many microcraters on the fiber surface formed by the sputter etching resulted in increase of surface area of the fiber and wettability, but the hydrophobic group was increased by the results of ESCA analysis. In particular the change in reflective index of the fibers was much more effective than the chemical composition of the fiber surface on increasing of the depth of shade.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.12 no.1
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• pp.45-49
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• 2003

Tensile strength of the woven glass fiber reinforced PET (Poly-Ethylene-Terephthalate) matrix composite manufactured by rapid press consolidation technique was investigated and evaluated. During pre-heating, consolidation and solidification stages, the optimal manufacturing conditions for this composite were discussed based on the void content and tensile properties depending on vacuum condition. It is found that the effect of vacuum condition during preheating gives a substantial difference on the strength as well as microstructure. It is also found that the failure micromechanism shows several energy absorption processes enhancing fracture toughness.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.15 no.3
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• pp.105-111
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• 2009

In this work, source reduction of poly ethylene terephthalate (PET) packaging are discussed as aspect of sustainability, such as reuse, refill and recycling through the various treatment methods and historical studies for municipal solid waste (MSW) disposal. Since PET has good chemical, physical and mechanical properties, and provides good oxygen and carbon dioxide barrier properties, PET is one of the most widely used thermoplastic polyester in the U.S. and around the world. As the demand for non-renewable PET is increasing, several approaches have been developed to meet economical feasibility and environmental responsibility without degrading material performance. Several companies, such as Coca-Cola Co., Easterform Packaging Co. and Kraft, have tried to develop lightweight PET bottle, and some of lightweight PET bottles are already commercialized. Reuse and refilling for PET container is well developed in Europe, such as Denmark, German and Netherland by supportive legislation and policies. Recycling process is the best way to economically reduce PET waste. In consequence, advanced technique and further development must be provided due to increasing PET packaging waste.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.33 no.10
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• pp.773-777
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• 2009

In this study, the strain sensing characteristics of single-wall carbon nanotubes(SWCNTs) networks were investigated to develop a film sensor for strain sensing. The SWCNTs film are formed on flexible substrates of poly(ethylene terephthalate) (PET) using spray process. In this manner we could control the transparency and obtain excellent uniformity of the networked SWCNT film. The carbon nanotube film is isotropic due to randomly oriented bundles of SWCNTs. Using experimental results it is shown that there is a nearly linear change in resistance across the film when it is subjected to tensile stress. The results presented in this study indicate the potential of such films for high sensitive transparent strain sensors on macro scale.

• Textile Coloration and Finishing
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• v.30 no.2
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• pp.70-76
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• 2018

The dyeing behaviors of poly(ethylene terephthalate)(PET) bulky yarns, DTY(draw textured yarn) and SSY(latent crimped yarn), were investigated with different energy type disperse dyes compared with those of SDY(spin draw yarn). The maximum exhaustions of E-type disperse Red 60, Blue 56 and Yellow 54 on SSY were 99%, 94% and 93%, respectively. The maximum exhaustions of S-type disperse Red 179, Blue 79 and Orange 30 on SSY were 96%, 97% and 97%, respectively. The K/S values of SSY were significantly higher than those of DTY and SDY in all energy type of disperse dyes. The knit fabric composed of SSY became bulky at the end of high temperature dyeing process because of their thermal shrinkage property due to melt viscosity difference.