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Diameter profile measurements for CO2 laser heated drawing process of PET fiber / W. Okumura in INTERNATIONAL POLYMER PROCESSING, Vol. XVIII, N° 1 (03/2003)
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Titre : Diameter profile measurements for CO2 laser heated drawing process of PET fiber Type de document : texte imprimé Auteurs : W. Okumura, Auteur ; T. Kanegae, Auteur ; Y. Ohkoshi, Auteur ; Y. Gotoh, Auteur ; M. Nagura, Auteur Année de publication : 2003 Article en page(s) : p. 46-52 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : Poly (ethylene terephthalate) (PET) fiber was heated by carbon dioxide laser radiation in the continuous drawing process. By this procedure, the position of the deformation region could be fixed precisely in the air. The location of neck-like deformation fluctuated within a range of about 0.2 mm for draw ratios of 4.0 to 4.5 and within a range of about 0.5 mm for draw ratios of 5.5 to 6.0, but the location fluctuated over a range of 1.0 mm for a draw ratio of 5.0. Fiber diameter profiles, which were used to calculate Hencky strain rate profiles and apparent elongational viscosity profiles, were obtained from high-speed video camera images of the deformation region. Regardless of draw ratio, apparent elongational viscosity exhibited almost the same minimum value. Apparent elongational viscosity is much lower than the value obtained by measurement at a low, constant strain rate, but the elongational stress acting at the point where apparent elongational viscosity begins to increase steeply (Hencky strain of about 1.0) is of the same order of magnitude as the reported value. For draw ratios less than 5.0, the temperature where apparent viscosity is lowest is about 100 to 120°C, which corresponds to the flow temperature of amorphous PET, whereas for draw ratios exceeding 5.0 the temperature where apparent viscosity is lowest is about 80°C, which corresponds to the glass transition temperature. Thus, the former corresponds to so-called neck-like deformation typically observed in high-speed spinning, and the latter corresponds to necking typically observed in cold drawing. These two types of deformation appear in turns for a draw ratio of 5.0, and therefore the location of the deformation region fluctuates greatly. This measurement system can be used as a high-strain-rate elongational rheometer for analyzing practical polymer processing systems, which can easily measure the precise on-line deformation history with a time resolution in the μs level. DOI : 10.3139/217.1717 En ligne : https://drive.google.com/file/d/18cpYQeUC2dJ8-nnMcvKYs8LJfHHYcDc-/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15850
in INTERNATIONAL POLYMER PROCESSING > Vol. XVIII, N° 1 (03/2003) . - p. 46-52[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 001023 - Périodique Bibliothèque principale Documentaires Disponible Direct measurement of fiber temperature in the continuous drawing process of PET fiber heated by CO2 laser radiation / W. Okumura in INTERNATIONAL POLYMER PROCESSING, Vol. XVII, N° 2 (06/2002)
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Titre : Direct measurement of fiber temperature in the continuous drawing process of PET fiber heated by CO2 laser radiation Type de document : texte imprimé Auteurs : W. Okumura, Auteur ; T. Yamaguchi, Auteur ; Y. Ohkoshi, Auteur ; Y. Gotoh, Auteur ; M. Nagura, Auteur Année de publication : 2002 Article en page(s) : p. 124-132 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : Poly(ethylene terephtalate) (PET) fiber was heated by carbon dioxide laser radiation during the continuous drawing process. Numerical calculation shows that the PET fiber can be heated much more rapidly and uniformly by heat radiation than by convective heat transfer through the fiber surface. During CO2 laser heated drawing, temperature in the vicinity of a neck-like deformation can be measured on-line with high precision, because the neck-like deformation is located within a range of 0.5 mm. We measured the fiber temperature profiles on the drawing process by IR thermometer that has a range resolution of 0.355 mm. The temperature at which neck-like deformation of the fiber initiates is higher than Tg when draw ratio is less than 4.5, but lower than Tg when draw ratio is more than 5.5. The maximum fiber temperature in the drawing process increases with draw ratio, up to 208°C for a draw ratio of 6.0. The rate of orientation-induced crystallization in the drawing process was estimated by comparison of measured temperature profiles with calculated temperature profiles. Note de contenu : - EXPERIMENTAL : Drawing system and material - Drawing tension - Density - Fiber temperature
- DISCUSSION : Comparison of radiation heating and conduction heating from fiber surface - Numeraical calculation of fiber temperature profiles
- APPENDIX : Absorption coefficient - Temperature distribution in the fiber cross-section - Absorptance of fiberDOI : 10.3139/217.1684 En ligne : https://drive.google.com/file/d/1eOzKEBB28dFq9HOJwrpxLtnhdtZ96iWb/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15932
in INTERNATIONAL POLYMER PROCESSING > Vol. XVII, N° 2 (06/2002) . - p. 124-132[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 001020 - Périodique Bibliothèque principale Documentaires Disponible Effects of take-up speed of melt spinning on the structure and mechanical properties of maximally laser drawn PA9-T fibers / A. J. Uddin in INTERNATIONAL POLYMER PROCESSING, Vol. XXI, N° 3 (07/2006)
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Titre : Effects of take-up speed of melt spinning on the structure and mechanical properties of maximally laser drawn PA9-T fibers Type de document : texte imprimé Auteurs : A. J. Uddin, Auteur ; T. Hara, Auteur ; R. Endo, Auteur ; M. Nagura, Auteur ; Y. Gotoh, Auteur ; Y. Ohkoshi, Auteur Année de publication : 2006 Article en page(s) : p. 263-271 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : A new semiaromatic polyamide, PA9-T, was melt-spun at takeup speeds from 200 to 1000 m min–1. The as-spun fibers were drawn with CO2 laser-heated drawing to their maximal draw ratio (DRmax). The drawing stress was recorded during this process. The effects of take-up speed of melt-spinning on maximally drawn fibers were characterized through measurements of density, birefringence, wide-angle X-ray diffraction, crystal orientation, tensile testing, and dynamic viscoelastic analysis. All as-spun fibers were essentially amorphous and their birefringence and density increased slightly with the increase of take-up speed. Lower take-up speeds yielded higher DRmax values, and fibers drawn to their DRmax exhibited superior structure and mechanical properties. The tensile strength and Young’s modulus achieved were the highest reported to date for PA9-T: 737 MPa and 5.8 GPa, respectively. DOI : 10.3139/217.0090 En ligne : https://drive.google.com/file/d/1la6EGiL1qawbKLNwPnxBa4dyGXnOoBZ3/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2840
in INTERNATIONAL POLYMER PROCESSING > Vol. XXI, N° 3 (07/2006) . - p. 263-271[article]Réservation
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Code-barres Cote Support Localisation Section Disponibilité 005042 - Périodique Bibliothèque principale Documentaires Disponible High-strength PET fibers produced by conjugated melt spinning and laser drawing / K. Nakata in INTERNATIONAL POLYMER PROCESSING, Vol. XXVII, N° 3 (07/2012)
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Titre : High-strength PET fibers produced by conjugated melt spinning and laser drawing Type de document : texte imprimé Auteurs : K. Nakata, Auteur ; F. Nakamura, Auteur ; Y. Ohkoshi, Auteur ; Y. Gotoh, Auteur ; M. Nagura, Auteur ; A. Hamano, Auteur ; S. Takada, Auteur ; Takeshi Kikutani, Auteur Année de publication : 2012 Article en page(s) : p. 386-391 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Fibres textiles -- Propriétés mécaniques
Fibres textiles synthétiques
Filature
Frittage laser
Polyéthylène téréphtalateIndex. décimale : 668.9 Polymères Résumé : The mechanical properties of conjugated-spun and laser drawn poly(ethylene terephthalate) (PET) fibers were investigated. The as-spun fibers used for the laser drawing were made by conjugated melt spinning with the copolymer of p-hydroxybenzoicacid and 2-hydroxy-6-naphthoicacid or polystyrene. The PET fibers prepared by conjugated spinning could be laser drawn to higher draw ratios under lower drawing stresses. The drawn fiber could be re-drawn up to a higher total draw ratio. Thus, a PET fiber having a tensile strength of 1.14 N/tex could be produced. DOI : 10.3139/217.2573 En ligne : https://drive.google.com/file/d/1KbHVwS8W9OJD0i0OtOzSsXpSiu88jshm/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15585
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Code-barres Cote Support Localisation Section Disponibilité 13995 - Périodique Bibliothèque principale Documentaires Disponible