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Analysis of a single screw extruder with a grooved plasticating barrel - Part I : the melting model / José Antonio Avila Alfaro in INTERNATIONAL POLYMER PROCESSING, Vol. XXX, N° 2 (05/2015)
[article]
Titre : Analysis of a single screw extruder with a grooved plasticating barrel - Part I : the melting model Type de document : texte imprimé Auteurs : José Antonio Avila Alfaro, Auteur ; Eberhardt Grünschloß, Auteur ; Stefan Epple, Auteur ; Christian Bonten, Auteur Année de publication : 2015 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Extrudeuse monovis
Matières plastiques -- Extrusion -- Appareils et matériels
Modèles mathématiques
Polymères -- Fusion
Prévision, Théorie de la
Vis barrièreIndex. décimale : 668.4 Plastiques, vinyles Résumé : Single screw extruders with barrier screws, grooved feed zones and grooved melting zones were introduced to the European plastics industry in 1999. These extruders have an improved melting and conveying capacity among other advantages, such as a lower melt temperature, less wear, less torque and less energy consumption. The aim of this paper is to present a mathematical model for predicting the melting rate in this type of extrusion system. Based on the classical melting mechanism observed in conventional extruders, it was possible to study the effect of the geometry of the grooved barrel on the melting rate of a polymer. It was shown that the grooves on the barrel notably increase the melting rate, when compared to conventional single screw extruders. A good agreement between theory and experimental data was found. Note de contenu : - THEORETICAL MODEL : Melting rate in the space between two grooves
- EXPERIMENTS : Model validation - Parameter study
- RESULTS AND DISCUSSION : Solid bed length validation - Melting rate validation - Parameter study - Extruder simulationDOI : 10.3139/217.3021 En ligne : https://drive.google.com/file/d/1ovEnaF589jCnoFhVELhjOll5L4VAA8D8/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=23911
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Code-barres Cote Support Localisation Section Disponibilité 17180 - Périodique Bibliothèque principale Documentaires Disponible Crystallization kinetics and multiple melting behavior of biodegradable poly(3-hydroxybutyrate-co-4-hydroxybutyrate) / B.-B. Tong in INTERNATIONAL POLYMER PROCESSING, Vol. XXXIII, N° 5 (11/2018)
[article]
Titre : Crystallization kinetics and multiple melting behavior of biodegradable poly(3-hydroxybutyrate-co-4-hydroxybutyrate) Type de document : texte imprimé Auteurs : B.-B. Tong, Auteur ; Y.-H. Ding, Auteur Année de publication : 2018 Article en page(s) : p. 669-676 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Calorimétrie
Cinétique chimique
Cristallisation
Diffractométrie de rayons X
Poly(3-hydroxybutyrate- co -4-hydroxybutyrate)
Polymères -- FusionIndex. décimale : 668.4 Plastiques, vinyles Résumé : The crystallization and melting behavior of biodegradable poly(3-hydroxybutyrate-co-4-hydroxybutyrate) [P(3HB-co-4HB)] with 11 % 4HB content was investigated by differential scanning calorimetry (DSC), small and wide angle X-ray scattering (SAXS and WAXS). The Avrami analysis was performed to obtain the kinetic parameters of crystallization. The results showed that the Avrami equation was suitable for describing the isothermal and nonisothermal crystallization processes of P(3HB-co-4HB). Based on the values of the equilibrium melting temperature and the half-time of crystallization, its nucleation constant of crystal growth kinetics was obtained by using the Lauritzen-Hoffman model, which was found to be 1.92 × 105 K2, lower than that for pure PHB. During the subsequent heating process, quite different multiple melting behaviors were observed for P(3HB-co-4HB) crystallized isothermally or nonisothermally. The origins of the multiple melting behaviors were discussed based on either the presence of dual lamellar thicknesses or the melt-recrystallization mechanism. In general, the crystallization and melting behaviors were elucidated by this work. Note de contenu : - EXPERIMENTAL SECTION : Materials - Differential scanning calorimetry - X-Ray measurements
- RESULTS AND DISCUSSION : Isothermal crystallization kinetics and melting behavior - Crystal growth analysis - Nonisothermal crystallization and melting behavior of P (3HB-co-4HB)DOI : 10.3139/217.3599 En ligne : https://drive.google.com/file/d/1UT-URNmOjBjTKXpkEvqjONtnlMnDCA8b/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=31406
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Code-barres Cote Support Localisation Section Disponibilité 20352 - Périodique Bibliothèque principale Documentaires Disponible Design and manufacture of an additive manufacturing printer based on 3D melt electrospinning writing of polymer / Behnam Akhoundi in INTERNATIONAL POLYMER PROCESSING, Vol. 38, N° 3 (2023)
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Titre : Design and manufacture of an additive manufacturing printer based on 3D melt electrospinning writing of polymer Type de document : texte imprimé Auteurs : Behnam Akhoundi, Auteur ; Vahid Modanloo, Auteur ; Ahmad Mashayekhi, Auteur Année de publication : 2023 Article en page(s) : p. 424-433 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Electrofilature
Fibres textiles synthétiques
Impression tridimensionnelle
Nanofibres
Poly-e-caprolactone
Polylactique, AcideL'acide polylactique (anglais : polylactic acid, abrégé en PLA) est un polymère entièrement biodégradable utilisé dans l'alimentation pour l'emballage des œufs et plus récemment pour remplacer les sacs et cabas en plastiques jusqu'ici distribués dans les commerces. Il est utilisé également en chirurgie où les sutures sont réalisées avec des polymères biodégradables qui sont décomposés par réaction avec l’eau ou sous l’action d’enzymes. Il est également utilisé pour les nouveaux essais de stent biodégradable.
Le PLA peut-être obtenu à partir d'amidon de maïs, ce qui en fait la première alternative naturelle au polyéthylène (le terme de bioplastique est utilisé). En effet, l'acide polylactique est un produit résultant de la fermentation des sucres ou de l'amidon sous l'effet de bactéries synthétisant l'acide lactique. Dans un second temps, l'acide lactique est polymérisé par un nouveau procédé de fermentation, pour devenir de l'acide polylactique.
Ce procédé conduit à des polymères avec des masses molaires relativement basses. Afin de produire un acide polylactique avec des masses molaires plus élevées, l'acide polylactique produit par condensation de l'acide lactique est dépolymérisé, produisant du lactide, qui est à son tour polymérisé par ouverture de cycle.
Le PLA est donc l’un de ces polymères, dans lequel les longues molécules filiformes sont construites par la réaction d’un groupement acide et d’une molécule d’acide lactique sur le groupement hydroxyle d’une autre pour donner une jonction ester. Dans le corps, la réaction se fait en sens inverse et l’acide lactique ainsi libéré est incorporé dans le processus métabolique normal. On obtient un polymère plus résistant en utilisant l'acide glycolique, soit seul, soit combiné à l’acide lactique.
Polymères -- FusionIndex. décimale : 668.4 Plastiques, vinyles Résumé : - Objectives : Electrospinning is one of the most well-known approaches to producing polymer nanofibers from a polymer solution by applying a potential difference (voltage) between the spinner and the collector, which is used in various industries such as medicine and military. This method has some significant restrictions, like low process efficiency due to the evaporation of the solvent, remaining solvent on the fibers, which are sometimes toxic, and inability to control the geometry of the produced fibers. On the other hand, preparing some solvents used in the electrospinning of polymer solutions is costly. Polymer melt electrospinning writing is a replacement for this type of electrospinning, which can be mentioned in terms of economy, efficiency, and production of solvent-free fibers. Therefore, in this research, a melt polymer electrospinning device was designed and manufactured according to existing extrusion-based additive manufacturing (AM) devices (3D printer).
- Methods : Changes in an extrusion-based 3D printer to convert it into a writing electrospinning device experimentally.
- Results : PLA and PCL fibers with diameters ranging from 8 to 84 μm were produced. The effect of process variables on the produced fibers’ diameter was investigated: Applied potential difference between the nozzle and the substrate: As its increases, the fiber diameter decreases. Increasing temperature: As its increases, the fiber diameter decreases. Distance between the nozzle and the substrate: As its increases, the fiber diameter increases. Flow rate: As its increases, the fiber diameter increases.
- Conclusions : By presenting a 3D printer-electrospinning device, it is possible to control the fiber’s diameter and the 3D geometry in the 3D printing-electrospinning process.Note de contenu : - The effect of the applied potential difference between the nozzle and the substrate on the diameter of the PLA fibers
- Effect of melting temperature on the diameter of the PLA fibers
- The effect of the distance between the nozzle and the substrate on the diameter of the PLA fibers
- The effect of variation in melt flow (extra extrusion multiplier) rate on the diameter of PLA fibers
- Investigating the possibility of controlling the fiber geometry
- Table 1 : Input parameters and their levelsDOI : https://doi.org/10.1515/ipp-2023-4352 En ligne : https://drive.google.com/file/d/1BOqMdf_6KdQ0sLWOTJWpgolfw0USqNLj/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39703
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Code-barres Cote Support Localisation Section Disponibilité 24318 - Périodique Bibliothèque principale Documentaires Disponible Estimation of bulk melt-temperature from in-mold thermal sensors for injection molding, part B : validation / G. A. Mendible in INTERNATIONAL POLYMER PROCESSING, Vol. XXXI, N° 3 (07/2016)
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Titre : Estimation of bulk melt-temperature from in-mold thermal sensors for injection molding, part B : validation Type de document : texte imprimé Auteurs : G. A. Mendible, Auteur ; David O. Kazmer, Auteur ; R. X. Gao, Auteur ; S. P. Johnston, Auteur Année de publication : 2016 Article en page(s) : p. 278-284 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Capteurs thermiques
Etat fondu (matériaux)
Matières plastiques -- Moulage par injection
Plan d'expérience
Polymères -- Fusion
Simulation par ordinateurIndex. décimale : 668.4 Plastiques, vinyles Résumé : An analytical method for estimating the bulk melt temperature in the injection molding process by means of in-mold temperature sensors was presented in Part A of this article. This method was validated using a transient cooling simulation of an injection molding process. The simulation considered the heat flux and heat accumulation in the mold starting from process startup until steady state was achieved. For the simulation, a full 3D model of the mold geometry was developed. The average coolant temperature and the initial cavity wall temperature were evaluated as boundary conditions. The first was found to provide a more accurate prediction of the bulk melt temperature although it increases the sensitivity of the method to the temperature measurement. Overall, the trends correlated well for both simulated and experimental data as well as the bulk temperature measurements. Note de contenu : - METHODOLOGY : Molding trials - Materials properties - Simulation
- RESULTS : Simulation accuracy - Validation of the prediction methodDOI : 10.3139/217.3024 En ligne : https://drive.google.com/file/d/1zgvr2KT5imM7WG9qIarnkjL5z5wy7eu_/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=26639
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Code-barres Cote Support Localisation Section Disponibilité 18175 - Périodique Bibliothèque principale Documentaires Disponible Experimental and theoretical study on screw filling in starve fed single screw extruders / Krzysztof J. Wilczynski in INTERNATIONAL POLYMER PROCESSING, Vol. XXXIII, N° 2 (05/2018)
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Titre : Experimental and theoretical study on screw filling in starve fed single screw extruders Type de document : texte imprimé Auteurs : Krzysztof J. Wilczynski, Auteur Année de publication : 2018 Article en page(s) : p. 171-179 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Extrudeuse monovis
Facteur de remplissage (technologie)
Matières plastiques -- Extrusion
Polyéthylène basse densité
Polyéthylène haute densité
Polymères -- Fusion
Pression
TempératureIndex. décimale : 668.4 Plastiques, vinyles Résumé : An extensive experimental and theoretical study has been performed on screw filling in starve fed/flood fed single screw extruders. The effect of screw speed, flow rate (level of starvation) and die geometry has been investigated. A “screw pulling-out” technique was used in the study. The solid conveying, melting positions, the extent of starvation, and the fully filled regions were observed. It was seen that filling of the screw increases with an increase of the flow rate at a fixed screw speed, and decreases with an increase of the screw speed at a fixed flow rate. The screw filling is strongly dependent on the die geometry and increases with an increase of the resistance of the die. The pressure was also measured, and it was observed that it considerably decreases with starvation. Mechanism of screw filling has been discussed. The simulations and experiments were performed for low density polyethylene (LDPE) and high density polyethylene (HDPE) at various operating conditions, both for starve fed and flood fed extrusion. Fill factor, pressure, temperature and melting profiles have been computed and validated experimentally. All the experimental observations were consistent with the simulations. Note de contenu : - Starve feeding vs. flood feeding
- Simulations
- Experimental validation of process simulationDOI : 10.3139/217.3386 En ligne : https://drive.google.com/file/d/1TFYZRY4IEBnZzYZJHwYR73VM1CoOIZyQ/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=30565
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Code-barres Cote Support Localisation Section Disponibilité 19873 - Périodique Bibliothèque principale Documentaires Disponible Filtration equipment for polymer melt lines / Stefan Vandendijk in CHEMICAL FIBERS INTERNATIONAL, Vol. 63, N° 4 (12/2013)
PermalinkFiltration equipment for polymer melt lines / Stefan Vandendijk in CHEMICAL FIBERS INTERNATIONAL, (10/2014)
PermalinkFusion bond epoxy for protection of metal pipes / Debi Prasad Mishra in PAINTINDIA, Vol. LXVII, N° 9 (09/2017)
PermalinkMatériaux thermoplastiques à base de biopolymère pour leur impression 3D par dépôt de fil fondu / Laurent Chaunier in RHEOLOGIE, Vol. 38 (12/2020)
PermalinkMelting mechanisms in corotating twin-screw extrusion : a critical review / Bruno Vergnes in INTERNATIONAL POLYMER PROCESSING, Vol. 39, N° 1 (2024)
PermalinkMelting model for starve fed single screw extrusion of thermoplastics / Krzysztof J. Wilczynski in INTERNATIONAL POLYMER PROCESSING, Vol. XXVIII, N° 1 (03/2013)
PermalinkMonitoring the production of polymer nanocomposites by melt compounding with on-line rheometry / S. T. Mould in INTERNATIONAL POLYMER PROCESSING, Vol. XXVII, N° 5 (11/2012)
PermalinkPlastiques. Résines phénoliques. Détermination de la plage de fusion par la méthode du tube capillaire - Norme NF T 51-435 / Association Française de Normalisation (Paris) / Saint-Denis La Plaine : Association Française de Normalisation (AFNOR) (1985)
PermalinkRhéologie dans la zone de transition cristallisation / fusion : application à des copolymères / M. Aris-Brosou in RHEOLOGIE, Vol. 30 (12/2016)
PermalinkSimulation of micropelletization mechanisms in polymer melt – air systems / Christian Schäfer in INTERNATIONAL POLYMER PROCESSING, Vol. XXXIII, N° 1 (03/2018)
PermalinkThe influence of different melt temperatures on the mechanical properties of injection molded PA-12 and the post process detection by thermal analysis / T. Meyer in INTERNATIONAL POLYMER PROCESSING, Vol. XXXII, N° 1 (03/2017)
PermalinkUnderstanding kneading holistically / Jochen Kettemann in KUNSTSTOFFE INTERNATIONAL, Vol. 110, N° 6 (2020)
PermalinkVerifying the melting behavior in single-screw plasticization units using a novel simulation model and experimental method / M. Aigner in INTERNATIONAL POLYMER PROCESSING, Vol. XXIX, N° 5 (11/2014)
PermalinkVirtual melting and feed section design / Christian Hopmann in KUNSTSTOFFE INTERNATIONAL, Vol. 103, N° 10 (10/2013)
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