Effect of mixing conditions and polymer particle size on the properties of polypropylene/graphite nanoplatelets micromoldings / Renze Jiang in INTERNATIONAL POLYMER PROCESSING, Vol. 37, N° 4 (2022)  

[article]  inINTERNATIONAL POLYMER PROCESSING > Vol. 37, N° 4 (2022) . - p. 372-382 Titre : Effect of mixing conditions and polymer particle size on the properties of polypropylene/graphite nanoplatelets micromoldings Type de document : texte imprimé Auteurs : Renze Jiang, Auteur ; Piyush Lashkari, Auteur ; Shengtai Zhou, Auteur ; Andrew N. Hrymak, Auteur Année de publication : 2022 Article en page(s) : p. 372-382 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation Composites à fibres -- Moulage par micro-injection Composites à fibres de graphite Conducteurs organiques Microstructures Nanoparticules Polypropylène Thermocinétique Index. décimale : 668.4 Plastiques, vinyles Résumé : In this study, properties of polypropylene/graphite nanoplatelets (PP/GNP) composites and corresponding micromoldings were systematically studied in terms of filler loading concentrations and mixing methods. PP of different forms, i.e., PP pellets and powders, were adopted to fabricate PP/GNP composites. Additionally, a comparative study of precoating GNP and PP powders using solvent-based solution blending and ultrasonication-assisted mixing was performed. Results showed that PP/GNP composites prepared using powder form PP resulted in at least one order of magnitude higher electrical conductivity than using pellet form PP and further reduced the percolation threshold from 12.5 to 10 wt%, which was related to the state of filler distribution within corresponding moldings. Morphology observations revealed that microparts prepared with powder-PP/GNP composites exhibited less preferential alignment of GNP particles along the flow direction when compared with those molded using pellet-PP/GNP counterparts, which was helpful in improving the overall electrical conductivity for PP/GNP micromoldings. Note de contenu : - EXPERIMENTAL SECTION : Materials - Sample preparation - CHARACTERIZATION : Electrical conductivity - Morphology - Differential scanning calorimetry - RESULTS AND DISCUSSION : Electrical conductivity - Morphology - Differential scanning calorimetry - Table 1 : Characteristic Data from DSC Scans for PP/GNP feeds (top row) and µIM microparts (bottom row). Cycle 1: 1st heating cycle. Cycle 2: cooling cycle. Cycle 3: 2nd heating cycle DOI : https://doi.org/10.1515/ipp-2022-0004 En ligne : https://drive.google.com/file/d/1qw8Ibyf-E7sqUi1vjl_V9cgnu7o1L3jN/view?usp=shari [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37913 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
23739	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Effect of the chemical and morphological conditions of the die wall on the extrusion of linear polyolefins / H. J. Larrazabal in INTERNATIONAL POLYMER PROCESSING, Vol. XXI, N° 2 (05/2006)  

[article]  inINTERNATIONAL POLYMER PROCESSING > Vol. XXI, N° 2 (05/2006) . - p. 132-140 Titre : Effect of the chemical and morphological conditions of the die wall on the extrusion of linear polyolefins Type de document : texte imprimé Auteurs : H. J. Larrazabal, Auteur ; John Vlachopoulos, Auteur ; Andrew N. Hrymak, Auteur Année de publication : 2006 Article en page(s) : p. 132-140 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : This study examines the effects of average surface roughness and composition of the die wall surface on the critical shear stress for the onset of instabilities in die extrusion. Increasing the average surface roughness of the die wall from 0.1 to 15 lm produced an increase of the critical shear stress for the onset of flow instabilities by as much as 20% during the extrusion of HDPE. The surface of the extrudates obtained with dies having an average surface roughness greater than 5 lm showed lines and grooves along the direction of extrusion. Chrome-plated and nickel-plated dies showed an average 28% increase in the critical shear stress as compared to conventional steel dies. The chemical composition of uncoated steel dies wall surfaces, including the presence of iron oxide, did not affect the critical shear stress for the onset of sharkskin significantly regardless of the type of resin used. DOI : 10.3139/217.0067 En ligne : https://drive.google.com/file/d/1Yxiub4WHfm2v8T1JdUQyyg_03cF_TsAl/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=2906 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
004675	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Electrical, morphological and thermal properties of microinjection molded polypropylene/multi-walled carbon nanotubes nanocomposites / S.-T. Zhou in INTERNATIONAL POLYMER PROCESSING, Vol. XXXIII, N° 4 (08/2018)  

[article]  inINTERNATIONAL POLYMER PROCESSING > Vol. XXXIII, N° 4 (08/2018) . - p. 514-524 Titre : Electrical, morphological and thermal properties of microinjection molded polypropylene/multi-walled carbon nanotubes nanocomposites Type de document : texte imprimé Auteurs : S.-T. Zhou, Auteur ; Andrew N. Hrymak, Auteur ; Musa R. Kamal Année de publication : 2018 Article en page(s) : p. 514-524 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Composites à fibres -- Moulage par micro-injection Composites à fibres de carbone Composites à fibres de carbone -- Propriétés électriques Composites à fibres de carbone -- Propriétés thermiques Mélanges-maîtres (chimie) Nanotubes de carbone à parois multiples Un nanotube de carbone multifeuillet est constitué de plusieurs feuillets de graphènes enroulés les uns autour des autres. Il existe deux modèles pour décrire la structure des nanotubes multifeuillets : - le modèle poupée russe: les plans de graphène sont arrangés en cylindres concentriques ; - le modèle parchemin: un seul feuillet de graphène est enroulé sur lui-même, comme une feuille de papier. Polypropylène Index. décimale : 668.4 Plastiques, vinyles Résumé : A series of polypropylene/multi-walled carbon nanotubes (PP/CNT) nanocomposites were prepared by masterbatch dilution, then followed by microinjection molding under a defined set of processing conditions. A micropart (μ-part) which has a three-step decrease in thickness along the flow direction was fabricated to study the effect of abrupt geometrical changes in mold cavities on the distribution of CNT in PP. To facilitate characterization, the μ-parts were divided into three sections based on thickness. The distribution of CNT within each section of subsequent μ-parts was evaluated by morphological observations and electrical resistivity measurements. In addition, the thermal properties of pure PP and PP/CNT nanocomposites as well as each section of subsequent μ-parts, were assessed by differential scanning calorimetry and thermogravimetric analysis. Note de contenu : - EXPERIMENTAL SECTION : Materials - Preparation of microparts - Characterization - RESULTS AND DISCUSSION : DC electrical resistivity and dielectric measurements - Morphology - Differential scanning calorimetry - Thermogravimetric analysis DOI : 10.3139/217.3541 En ligne : https://drive.google.com/file/d/1D1_reEOphAhQ8gOARPxFYLxIFILFle_z/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=30891 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
20077	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Flow instabilities of linear PE in capillary dies / H. J. Larrazabal in INTERNATIONAL POLYMER PROCESSING, Vol. XVII, N° 1 (03/2002)  

[article]  inINTERNATIONAL POLYMER PROCESSING > Vol. XVII, N° 1 (03/2002) . - p. 44-48 Titre : Flow instabilities of linear PE in capillary dies : Materials of construction of dies Type de document : texte imprimé Auteurs : H. J. Larrazabal, Auteur ; Andrew N. Hrymak, Auteur Année de publication : 2002 Article en page(s) : p. 44-48 Note générale : Bibliogr. Langues : Anglais (eng) Index. décimale : 668.9 Polymères Résumé : Flow instabilities of linear polyethylenes have been studied in capillary dies. The effect of shear stress temperature, molecular weight and material of construction of the dies on both the critical shear stress for the onset of slip and slip velocities have been evaluated. Flow curves were obtained using capillary dies with constant L/D and different diameters. Slip velocities were calculated using the Mooney technique [1] as a function of sheer stress. The onset of slip and slip velocity are affected by the material of construction of the capillary die. Flow instabilities were eliminated when brass dies were used under specific conditions. Instabilities persisted when naval brass and copper capillary dies were used. DOI : 10.3139/217.1673 En ligne : https://drive.google.com/file/d/1YsuibdPYsbZrDZ-ak1B_zmec4APkdO4R/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15960 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001019	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Flow stabilization and coating thickness reduction through use of multi-slot air-knife in gas jet wiping / J. R. McDermid ; Andrew N. Hrymak ; F. E. Goodwin in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 19, N° 1 (01/2022)  

[article]  inJOURNAL OF COATINGS TECHNOLOGY AND RESEARCH > Vol. 19, N° 1 (01/2022) . - p. 143-158 Titre : Flow stabilization and coating thickness reduction through use of multi-slot air-knife in gas jet wiping Type de document : texte imprimé Auteurs : J. R. McDermid, Auteur ; Andrew N. Hrymak, Auteur ; F. E. Goodwin, Auteur Année de publication : 2022 Article en page(s) : p. 143-158 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Fluides, Mécanique des Galvanisation Matériaux -- Epaisseur Revêtements Tags : 'Balayage  au  jet  de  gaz'  'Réduction  l'épaisseur  du  revêtement'  'Lame  d'air  multi-fentes'  'Galvanisation  à  chaud  continue'  'Modélisation  des  turbulences'  'Mesures  d'épaisseur Index. décimale : 667.9 Revêtements et enduits Résumé : This paper investigates the gas jet wiping process, which is widely employed for controlling the final zinc-alloy coating thickness of a moving steel strip in the continuous hot-dip galvanizing process. In this study, large eddy simulation (LES) was employed to determine the effect of lower velocity symmetric auxiliary jets on main jet stabilization and coating thickness reduction during the gas jet wiping process. For validation purposes, experimental measurements of coating thickness were also carried out for the prediction of final coating thickness via a novel prototype multi-slot air knife used as the wiping actuator. Good agreement was found between the experimental measurements and model predictions for the coating weight, which also confirmed the applicability of the Elsaadawy et al.1 model for the prediction of final coating weight for the multi-slot air knife geometry used. It was found that the jet flapping observed during single jet wiping could be prevented through use of the multi-slot air knife operating with lower velocity symmetric auxiliary jets (Rea/Rem =  0.45) situated on both sides of the main jet. The auxiliary jets modified the flow field in the main jet shear layer and diminished the formation of alternating vortices, which are the main cause of jet flow oscillations. As a result, a stabilized impinging flow with a longer potential core was found for the multi-slot jet configuration. This led to increased pressure gradient and increased shear stresses in the vicinity of the wiping region and, consequently, lower coating weights were obtained through use of the multi-slot air knife compared to the conventional single slot jet. Note de contenu : - Analytical model of film thickness - Experimental setup - Numerical simulation - Results and discussion - Table 1 : Working liquid properties in the experimental facility DOI : https://doi.org/10.1007/s11998-021-00570-1 En ligne : https://link.springer.com/content/pdf/10.1007/s11998-021-00570-1.pdf Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=37152 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
23313	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Influence of mold cavity thickness on electrical, morphological and thermal properties of polypropylene/carbon micromoldings / Shengtai Zhou in INTERNATIONAL POLYMER PROCESSING, Vol. 38, N° 2 (2023)  

Permalink

Modeling short-range interactions in concentrated newtonian fiber bundle suspensions / N. Meyer in INTERNATIONAL POLYMER PROCESSING, Vol. 36, N° 3 (2021)  

Permalink

Nozzle injection of physical blowing agents in the injection molding of microcellular foams / V. L. Bravo in INTERNATIONAL POLYMER PROCESSING, Vol. XX, N° 2 (06/2005)  

Permalink

Numerical investigation of multiple-slot jets in air-knife wiping / A. Yahyaee Soufiani in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 14, N° 5 (09/2017)  

Permalink

Numerical simulation of the dip-coating process with wall effects on the coating film thickness / Mahyar Javidi in JOURNAL OF COATINGS TECHNOLOGY AND RESEARCH, Vol. 12, N° 5 (09/2015)  

Permalink

---

1 (1 - 10 / 10)