• Title/Summary/Keyword: PTT

검색결과 339건 처리시간 0.211초

Effect of Heat-treatment on Stretch of Poly(trimethylene terephthalate) Woven Fabric

  • Yoon, Kwan-Han;Jeong, Young-Jin;Min, Byung-Ghyl
    • Fibers and Polymers
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    • 제4권2호
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    • pp.84-88
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    • 2003
  • The properties of a woven fabric made of poly(trimethylene terephthalate) (PTT) were investigated. The PTT fab-ric of draw textured yarn (DTY) showed excellent stretch as good as a fabric containing spandex. However, the unique stretch of the PTT fabric reduced dramatically by simple heat-treatment even at as low as $80^{\circ}C$. To understand the phenomenon, the crimp rigidity of the DTY was observed by SEM. It was found that the drastic reduction of stretch was caused by irreversible uncrimping of PTT DTY after heat-treatment. Conclusively, it is of importance to optimize the texturing conditions for PTT DTY to make the crimp more stable.

PTT 섬유의 염색성 (2) - 용제 처리한 PTT 섬유의 염색성 및 물성 - (Dyeing Properties of PTT Fiber (2) - Effect of Solvent Treatment on Dyeing and Physical Properties of PTT Fiber -)

  • 이두환;정동석;김호정;이문철
    • 한국염색가공학회지
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    • 제15권4호
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    • pp.8-16
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    • 2003
  • Poly(trimethylene terephthalate)(PTT) fiber was pretreated with organic solvent/water solution of various compositions. The organic solvents used in this experiment were benzyl alcohol, n-buthanol, and N,N-dimethylformamide(DMF). Density of the fibers were investigated as a measure of crystallite region. The dye uptake increased in the order of pretreatment with hot water < untreated < 5% benzyl alcohol < 100% benzyl alcohol < 90% benzyl alcohol; hot water < untreated $\risingdotseq$ 5% butanol < 100% beutanol < 90% butanol; hot water $\risingdotseq$ 5% DMF < untreated < 90% DMF < 100% DMF. The dye uptake increases with increase of crystallinity. It seems likely that the recrystallization process during the pretreatment with organic solvent/water solutions leads to an increase in the microvoid and then a large increase in the dye uptake. Also the dyeing rate increased and the dyeing transition temperature decreased with the pretreatments. The results obtained are corresponds with the plasticization of the fiber structure formed during the pretreatrnent.

초음파 재활치료 시 PTT와 생리변수의 상관관계 분석 (Analysis of Relations Between Physiologic Parameters and Pulse Transit Time on the Ultrasound Therapy)

  • 김성민;최상혁;이만표;최병철;정회승;박성윤
    • 전기학회논문지
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    • 제56권8호
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    • pp.1514-1520
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    • 2007
  • Currently, the signal of the human body is measured with various methods, and a noninvasive investigation of various methods is useful diagnosis method. PTT(Pulse Transit Time) which is noninvasive investigation make use of to estimate the physiological phenomena. PTT has a latent information of cardiovascular system. So we have the experiments for analysis of the relations between PTT and physiological parameters. We examine to correlate to the physiological parameters, an age and degree of paralysis on the ultrasound therapy. The 40 patients who has a such paralysis join our experiment, and we obtain the PTT data that normal condition and states after ultrasound therapy. We study that PTT after the ultrasound therapy for patients who have a paralysis was related to an age and degree of paralysis.

분산염료에 의한 Poly(trimethylene terephthalate) 섬유의 염색거동의 해석 (The Interpretation of Dyeing Behavior of Poly(trimethylene terephthalate) Fiber with a Disperse Dye)

  • 윤석한;김태경;임용진;조규민
    • 한국염색가공학회지
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    • 제13권4호
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    • pp.249-255
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    • 2001
  • To interpret the dyeing behavior of PTT fiber with C. I. Disperse Violet 1, the thermodynamic Parameters of dyeing, such as standard affinity, heat of dyeing(enthalpy change), entropy change, diffusion coefficient, and activation energy of diffusion, were obtained from isotherms and dyeing rates at various temperatures and compared with those of PET fiber. The heat of dyeing(enthalpy change) and the entropy change of PTT fiber showed smaller negative values than those of PET fiber. This means that the dye molecules in the PTT fiber are combined more loosely than in the PET fiber and that is due to the flexibility of polymer chains of PTT fiber. The diffusion coefficients of C. I. Disperse Violet 1 into the PTT fiber were larger than those for PET fiber, and the activation energy of diffusion on PTT fiber was smaller than that on PET fiber.

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IMS망에서 PTT서비스의 통화 처리 성능 향상을 위한 프로토콜 압축 기법 (A Protocol Compression Scheme for Improving Call Processing of Push-To-Talk Service over IMS)

  • 정인환
    • 한국멀티미디어학회논문지
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    • 제12권2호
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    • pp.257-271
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    • 2009
  • 본 논문에서는 유/무선 통합 패킷 망인 IMS(IP Multimedia Subsystem)에서 대표적인 응용 서비스인 PTT(Push-To-Talk) 서비스의 통화 처리 성능 향상을 위한 프로토콜 압축 기법을 제안한다. IMS망에서 PTT서비스를 하기 위해서는 현재 상용화 되어있는 Mobile망과 TRS(Trunked Radio System)망과 동일한 호 설정을 가져야 하며 다수의 단말기들 사이에 동일한 내용을 실시간으로 교환할 수 있어야하기 때문에 빠른 호 설정 및 통화 시에 대역특이 충분해야한다. 본 논문에서 제안한 A+SigComp기법은 PTT의 호 설정 프로토콜인 SIP의 세션 설정 단계의 지연 시간을 약 10% 줄였으며 A+ROHC기법은 음성 통화시 교환되는 RTP 헤더의 크기를 줄임으로써 전송 효율 약 5% 높였다.

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PTT를 이용한 자전거 운동 중 지속적인 혈압의 예측 (Continuous Blood Pressure Prediction Using PTT During Exercise)

  • 김철승;문기욱;권정훈;엄광문
    • 대한의용생체공학회:의공학회지
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    • 제27권6호
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    • pp.370-375
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    • 2006
  • The purpose of this work is to predict the systolic blood pressure (BP) during exercise from pulse transit time (PTT) for warning of possible danger. PTT was calculated as the time between R-peak of ECG and the peak of differential photoplethysmograph (PPG). For the PTT-BP model, we used regress equations from previous studies and 3 kinds of new models combining linear and nonlinear regress equation. The model parameters were estimated with the data measured under low to middle intensity exercise, and then was tested with the data measured under high intensity exercise. Predicted BP values after high intensity exercise were compared with those measured by cuff-type sphygmomanometer. The results showed that the error between measured and predicted values were acceptable for the monitoring BP. We tested PTT-BP models 1 month after the identification without further calibration. Models could predict the BP and the errors between measured and predicted BP were about 5mmHg. The suggested system is expected to be helpful in recognizing any danger during exercise.

Thermal Properties of Poly(trimethylene terephthalate)/ Poly(ethylene terephthalate) Melt Blends

  • Son, Tae Won;Kim, Kwang Il;Kim, Nam Hun;Jeong, Min Gi;Kim, Young Hun
    • Fibers and Polymers
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    • 제4권1호
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    • pp.20-26
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    • 2003
  • The thermal behavior, morphology, ester-interchange reaction of Poly(trimethylene terephthalate) (PTT)/poly(ethylene terephthalate) (PET) melt blends were investigated over the whole composition range(xPTT/(1-x)PET) using a twinscrew Brabender. The melt blends were analyzed by differential scanning calorimetry (DSC), nuclear magnetic resonance spectroscopy ($^{13}{C-NMR}$), and scanning electron microscopy (SEM). Single glass transition temperature ($T_g$) and cold crystallization temperature ($T_cc$) were observed in all melt blends. Melt blends were found to be due to the ester-interchange reaction in PTT/PET blend. Also the randomness of copolymer increases because transesterification between PT and PET increases with increasing blending time This reaction increases homogeneity of the blends and decreases the degree of crystallinity of the melt blends. In PTT-rich blends, mechanical properties decrease with increase of PET content compared with that of pure PTT. And, in PET-rich blends, tensile modulus decreases with increase of PTT content, but tensile strength and elongation is similar to that of pure PET.

Hydrolytic Degradation of Synthetic Polytrimethylene Terephthalate and Characterization by MALDI-TOF Mass Spectrometry

  • Yang, Eun-Kyung;Jang, Sung-Woo;Cho, Young-Dal;Choe, Eun-Kyung;Park, Chan-Ryang
    • Bulletin of the Korean Chemical Society
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    • 제32권2호
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    • pp.477-482
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    • 2011
  • The structural analysis of polytrimethylene terephthalate (PTT) and characterization of the hydrolytic degradation products after acid hydrolysis were performed using MALDI-TOF mass spectrometry. Mass spectra of the PTT samples were analyzed using a self-calibration method as well as an internal calibration method with standard materials of known masses. PTT structures constituting the samples were determined from the analyses of the spectra, and their relative compositions were estimated. The MALDI-TOF mass spectra of the acid-hydrolyzed PTT sample showed three main series of oligomer products with different end groups in accordance with the hydrolysis schemes. From the spectra of both $Na^+$ and $K^+$ adducts, it was concluded that the PTT samples have higher affinity for $Na^+$ compared with $K^+$ and therefore show higher ionization efficiency with sodium ions when dithranol is used as a matrix. Two different wavelength laser beams ($\lambda$ = 337 nm and 355 nm) were tested and it was observed that the 355 nm beam was more efficient in obtaining the MALDI spectra of PTT using dithranol as a matrix under our experimental conditions.

감성의류용 형상기억 PP직물 소재 개발과 물성분석 (Development and Analysis of Physical Property of PP Shape Memory Fabrics for Emotional Garment)

  • 김현아;김승진
    • 감성과학
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    • 제14권1호
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    • pp.117-126
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    • 2011
  • 이 연구는 감성의류용 형상기억 메모리직물의 제조 방법과 물성을 조사하기 위해 저온열처리와 정장열처리 가연법을 폴리프로필렌 POY와 SDY에 각각 적용하고 이들 사를 사용하여 PP형상기억메모리 직물을 air-jet직기에서 제조하였다. 물성비교를 위해서 PET와 PTT형상기억메모리 직물도 같이 제직하여 4가지 형상기억 메모리 직물시료를 만들고 이들의 여러 가지 물성을 측정 비료분석하여 다음과 같은 결론을 얻었다. PP형상기억 메모리 직물에 사용하기 위해 저온가연법과 정장열처리법에 의해 만든 PP가연사의 물성은 절단강 신도가제직성에 문제가 없는 값을 가졌으며 특히 열수축율이 습열은 1.5% 이하 건열은 3~5% 범위를 가짐으로써 PTT의 5~8%의 높은 열수축율에 비해 열적 안정성을 가졌다. PP형상기억 메모리 소재의 변형된 형태를 유지하는 소성적 성능 특성 평가법인 Toray 방추성 평가는 PP소재가 PTT와 같은 5급을 나타냄으로써 우수한 변형 유지특성을 보였다. 또한 PP형상기억 메모리소재의 보온성은 PTT소재보다 약 56% 향상된 결과를 보였으며 스프레이법에 의한 발수성은 PTT소재에 발수처리한 소재와 동일하게 5급의 우수한 발수성을 보였다. 그리고 PP형상기억 메모리소재의 형상기억 특성을 평가 할 목적으로 3D 이미지 방법과 카메라 측정결과 PTT소재와 비슷한 형상기억 특성을 보임을 확인 할 수 있었다.

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PET와 PTT사의 열처리후 물성변화 (Change of physical property on PET and PTT yarn after heat treatment)

  • 김일래;김광수
    • 한국섬유공학회:학술대회논문집
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    • 한국섬유공학회 2003년도 봄 학술발표회 논문집
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    • pp.337-338
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    • 2003
  • PTT(poly trimethylene terephthalate)섬유는 PET(polyethylene terephthalate)섬유에 비하여 탄성 (elasticity)가 우수하고 염색성이 PET와 유사한 점에서 차세대섬유로 분류되고 있다. 분자의 구조가 trans-trans의 fully extended chain(rod shape)형태인 PET에 비하여 trans-gauche-gauche-trans의 스프링과 같은 extended zigzag(helix shape)이어서 탄성회복성이 우수하다. 또한 PTT의 탄성계수값은 PET에 비하여 $\frac{1}{2}$정도이다. 의복을 착용중 신장과 수축을 반복하는 과정에서 섬유는 탄성을 점차 상실하게 되는데, 이 응력완화의 변화특성에 따라서 착용감이 영향을 끼친다. (중략)

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