![](./images/home.jpg)
![](./images/bar_spacer.gif)
Détail de l'auteur
Auteur Adhemar C. Ruvolo-Filho |
Documents disponibles écrits par cet auteur
![](./images/expand_all.gif)
![](./images/collapse_all.gif)
![](./images/orderby_az.gif)
Effect of blending protocol on the rheological properties and morphology of HDPE and LLDPE blend-based nanocomposites / Fabio R. Passador in INTERNATIONAL POLYMER PROCESSING, Vol. XXVII, N° 3 (07/2012)
![]()
[article]
Titre : Effect of blending protocol on the rheological properties and morphology of HDPE and LLDPE blend-based nanocomposites Type de document : texte imprimé Auteurs : Fabio R. Passador, Auteur ; Adhemar C. Ruvolo-Filho, Auteur ; L. A. Pessan, Auteur Année de publication : 2012 Article en page(s) : p. 378-385 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Alliages polymères
Anhydride maléique
Matériaux hybrides
Montmorillonite
Polyéthylène basse densité linéaire
Polyéthylène haute densité
Rhéologie
Structure cristalline (solide)Index. décimale : 668.4 Plastiques, vinyles Résumé : Nanocomposites based on high density polyethylene (HDPE)/linear low density polyethylene (LLDPE) blend were prepared by melt compounding in a torque rheometer using an organoclay (montmorillonite) as nano-filler and maleic anhydridegrafted linear low density polyethylene (LLDPE-g-MA) as compatibilizer. The effects of five blending protocols on microstructure, crystallinity and rheological properties of the prepared samples were examined. The steady state rheological properties showed that the addition of nanoclay to the HDPE/LLDPE blend increased its shear viscosity at low shear rates changing the behavior of the HDPE/LLDPE matrix to a more pronounced shear thinning behavior. The blending sequence (LLDPE/LLDPE-g-MA/20A)/HDPE (where LLDPE and LLDPE-g-MA were first mixed with organoclay and then this system was later blended with HDPE) showed a lower slope of the log g versus log γ curve and these results can be an indicative that the interactions between the matrix and the organoclay are stronger. The organoclay interlayer spacing and the crystallinity of the polymer domains were also influenced by the blending sequence. The crystallinity was calculated through the mathematical deconvolution of the peaks observed in the WAXD profiles. Overall, the crystallization of HDPE in the blends was hardly influenced by the presence of LLDPE. The blending sequence (LLDPE/LLDPE-g-MA/20A)/HDPE showed lower cristallinity when compared to others blending sequences. On the other hand, it was observed an increase in the organoclay interlayer spacing of this nanocomposite because the intercalation and/or exfoliation process occurs preferentially in the amorphous phase. DOI : 10.3139/217.2567 En ligne : https://drive.google.com/file/d/1lIQb9pM2Akh7QBUAGlF6qeWHZhiQIMFK/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15584
in INTERNATIONAL POLYMER PROCESSING > Vol. XXVII, N° 3 (07/2012) . - p. 378-385[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 13995 - Périodique Bibliothèque principale Documentaires Disponible Evaluating barrier properties of organic coatings by water permeation and electrochemical methods / P. C. Inone in JOURNAL OF COATINGS TECHNOLOGY (JCT), Vol. 75, N° 939 (04/2003)
[article]
Titre : Evaluating barrier properties of organic coatings by water permeation and electrochemical methods Type de document : texte imprimé Auteurs : P. C. Inone, Auteur ; C. M. Garcia, Auteur ; Adhemar C. Ruvolo-Filho, Auteur Année de publication : 2003 Article en page(s) : p. 29-36 Note générale : Bibliogr. Langues : Américain (ame) Tags : Absorption eau Impédance surface Peinture anticorrosion Epaisseur couche Protection corrosion Etude expérimentale Propriété physique Spectrométrie Méthode électrochimique Essai perméabilité Epoxyde résine Matériau revêtement Vernis Index. décimale : 667.9 Revêtements et enduits Résumé : Water permeation, water absorption, d.c. resistance, and electrochemical impedance spectroscopy (ElS) measurements were performed on films of epoxy-polyamide used as binder in paint formulations. Barrier properties were found to be highly dependent upon the thickness of films. In thick films, water permeation measurements revealed the presence of pathways attributed to frozen holes, through which the flow is not governed by diffusion. In thin films, the presence of pinholes was detected by d.c. resistance and ElS measurements. Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=5592
in JOURNAL OF COATINGS TECHNOLOGY (JCT) > Vol. 75, N° 939 (04/2003) . - p. 29-36[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 000564 - Périodique Bibliothèque principale Documentaires Disponible Influence of blending protocol on the thermal and mechanical properties of HDPE/LLDPE blend-based nanocomposites / Fabio R. Passador in INTERNATIONAL POLYMER PROCESSING, Vol. XXXI, N° 4 (08/2016)
![]()
[article]
Titre : Influence of blending protocol on the thermal and mechanical properties of HDPE/LLDPE blend-based nanocomposites Type de document : texte imprimé Auteurs : Fabio R. Passador, Auteur ; Adhemar C. Ruvolo-Filho, Auteur ; L. A. Pessan, Auteur Année de publication : 2016 Article en page(s) : p. 472-481 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Alliages polymères
Alliages polymères -- propriétés mécaniques
Alliages polymères -- Propriétés thermiques
Anhydride maléique
Charges (matériaux)
Copolymères greffés
Matériaux hybrides -- Propriétés mécaniques
Matériaux hybrides -- Propriétés thermiques
Montmorillonite
Nanoparticules
Polyéthylène basse densité linéaire
Polyéthylène haute densité
Polyéthylène maléate
RhéométrieIndex. décimale : 668.4 Plastiques, vinyles Résumé : Nanocomposites based on high density polyethylene (HDPE)/linear low density polyethylene (LLDPE) blend were prepared by melt compounding in a twin-screw extruder using an organoclay (montmorillonite) as nano-filler and maleic anhydride-grafted linear low density polyethylene (LLDPE-g-MA) as compatibilizer. The effects of two blending protocols were also investigated. In the first blending protocol LLDPE and LLDPE-g-MA were first reinforced with organoclay and then this nanocomposite was later blended with HDPE, and the second blending protocol LLDPE-g-MA was mixed with organoclay first and then this masterbatch was diluted with HDPE and LLDPE. The preparation of the masterbatch resulted in the degradation of polyethylene, with crosslinking formation which increase the viscosity of the polymer and facilitated the dispersion of the organoclay in the polymeric matrix. WAXD and TEM were used to determine the effect of blending protocol and organoclay content on the intercalation and mechanical properties. The introduction of a maleated polyethylene was required to improve the organoclay dispersion in the nanocomposites. Thermal and mechanical properties of the nanocomposites were affected by blending protocols and the content of organoclay. The degree of crystallinity of the materials prepared using the first blending protocol decreased upon the intercalation of clay platelets whereas for the materials obtained using the second blending protocol the degree of crystallinity decreased due the crosslinking which further restricted mobility and diffusion of polymer chains. The nanocomposites show higher values of tensile modulus, flexural modulus and HDT compared to the blend without the addition of organoclay. The OMMT content added to the polymer blend results in significant and well correlated improvements in tensile and flexural moduli. Note de contenu : - EXPERIMENTAL : Materials - Melt processing - Swelling measurements - Nanocomposite preparation - Characterization of the nanocomposites
- RESULTS AND DISCUSSION : Rheometric torque curves - WAXD and TEM analysis - Thermal properties - Mechanical propertiesDOI : 10.3139/217.3238 En ligne : https://drive.google.com/file/d/1SjcBsX-9U4ulsD2GK9mQjCy-2SsOns42/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=26809
in INTERNATIONAL POLYMER PROCESSING > Vol. XXXI, N° 4 (08/2016) . - p. 472-481[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 18238 - Périodique Bibliothèque principale Documentaires Disponible LLDPE/proton exchanged layered niobate K4Nb6O17 nanocomposites / H. Otaguro in INTERNATIONAL POLYMER PROCESSING, Vol. XXVII, N° 4 (08/2012)
![]()
[article]
Titre : LLDPE/proton exchanged layered niobate K4Nb6O17 nanocomposites Type de document : texte imprimé Auteurs : H. Otaguro, Auteur ; Adhemar C. Ruvolo-Filho, Auteur Année de publication : 2012 Article en page(s) : p. 406-413 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Charges (matériaux)
Diffractométrie de rayons X
Extrudeuse bi-vis
Matériaux hybrides
Microscopie électronique à balayage
Nanoparticules
Oxydes lamellaires
Polyéthylène basse densité linéaire
Potassium niobate -- Synthèse
ThermogravimétrieIndex. décimale : 668.4 Plastiques, vinyles Résumé : The potassium hexaniobate was synthesized by reacting, in stoichiometric proportions, Nb2O5and K2CO3at 1100 °C and modified with octadecylamine from an acid-base reaction. Through X-ray diffraction, an interlayer space of 4.27 nm was observed in comparison with 0.79 nm of unmodified oxide; this was also shown by SEM microscopy. The hybrid nanofiller previously obtained was incorporated into LLDPE by melt intercalation (0 up to 10 wt.%) using a twin screw extruder and LLDPE-g-MAH as compatibilizer. From TGA results, all nanocomposites (LLDPE/LLDPE-g-MAH/lamellar oxide) have increased the onset degradation temperature, while the oxide lost during processing for LLDPE/LLDPE-g-MAH/lamellar oxide nanocomposites was higher for the highest content in comparison with LLDPE matrix. According to the Eyring equation, the activation volume of the samples could be calculated using the relationship between the yield strength and strain rate from tensile stress-strain curves. The activation volume decreased with increase of nanofiller concentration, suggesting a good adhesion between the layered oxide and the polymeric matrix for high concentration. This can be attributed to the restricted segmental motion near the nanofiller/polymeric interface, while a poor interaction between them was observed for low concentration. However, the Young’s modulus showed a 50% improvement for low nanofiller concentration, especially in the case of 1 wt.% of nanofiller, which was also confirmed by modulus and toughness balance. Considering all the results, it has been revealed that the proton exchanged layered niobate can improve the thermal and mechanical properties of LLDPE/LLDPE-g-MAH/lamellar oxide nanocomposites. DOI : 10.3139/217.2384 En ligne : https://drive.google.com/file/d/1dJ8StmaAO34Z82B_aOwgI1c7UFU9VUA5/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=15702
in INTERNATIONAL POLYMER PROCESSING > Vol. XXVII, N° 4 (08/2012) . - p. 406-413[article]Réservation
Réserver ce document
Exemplaires (1)
Code-barres Cote Support Localisation Section Disponibilité 14087 - Périodique Bibliothèque principale Documentaires Disponible