Direct measurement of the constrained polymer region in polyamide/clay nanocomposites and the implications for gas diffusion

Adame, Daniel; Beall, Gary W.

doi:10.1016/j.clay.2008.03.005

Cited by 148 publications

(83 citation statements)

References 19 publications

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“…The improved barrier properties of polymer-clay nanocomposites seem to be due to a increased tortuosity of the diffusive path for permeants (Figure 2), forcing them to travel a longer path to diffuse through the film. This theory was developed by Nielsen (1967) and was further corroborated by other authors (Mirzadeh & Kokabi, 2007;Adame & Beall, 2009). The increase in path length is a function of the aspect ratio of the clay and the volume fraction of the filler in the composite.…”

Section: Fig 1 Types Of Composites From Polymer-clay Interactionssupporting

confidence: 69%

“…The increase in path length is a function of the aspect ratio of the clay and the volume fraction of the filler in the composite. Nielsen's model has been used effectively to predict permeability of systems at clay loadings of less than 1%, but some experimental data have reported much lower permeabilities than predicted at higher loadings (Adame & Beall, 2009). Beall (2000) proposed a new model to predict permeability of nanocomposites focused on the polymer-clay interface as an additional governing factor to the tortuous path, thus providing a correction factor to Nielsen's model.…”

Section: Fig 1 Types Of Composites From Polymer-clay Interactionsmentioning

confidence: 99%

See 1 more Smart Citation

Nanocomposites in Food Packaging – A Review

Azeredo¹,

Mattoso²,

McHugh³

2011

Advances in Diverse Industrial Applications of Nanocomposites

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Section: Fig 1 Types Of Composites From Polymer-clay Interactionssupporting

confidence: 69%

Section: Fig 1 Types Of Composites From Polymer-clay Interactionsmentioning

confidence: 99%

Nanocomposites in Food Packaging – A Review

Azeredo¹,

Mattoso²,

McHugh³

2011

Advances in Diverse Industrial Applications of Nanocomposites

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“…Hence much attention has been paid to obtain such morphologies, characterized by a high degree of clay exfoliation. However, the simple tortuous path model which considers the nanocomposite as an ideal binary system can not explain some experimental observations in the literature that yield either much lower [43][44][45] or on the contrary much higher permeability values than predicted [22,[28][29][30]. New conceptual approaches consisting in considering heterogeneous materials as resulting from three phases, namely the continuous phase, the dispersed phase and the interface, have progressively come to light [22,28,30,[43][44][45][46][47].…”

Section: Introductionmentioning

confidence: 99%

Reinforcement of the Gas Barrier Properties of Polyethylene and Polyamide Through the Nanocomposite Approach: Key Factors and Limitations

Picard

Gérard

Espuche

2013

Oil Gas Sci. Technol. – Rev. IFP Energies nouvelles

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Re´sume´-Renforcement des proprie´te´s barrie`re aux gaz de matrices polye´thyle`ne et polyamide par l'approche nanocomposite : facteurs cle´s et limitations -Dans cette e´tude, des nanocomposites sont pre´pare´s par voie fondue pour deux matrices, une matrice polyamide 6 (PA6) et une matrice polye´thyle`ne (PE), leur morphologie ainsi que leurs proprie´te´s barrie`res sont e´tudie´es. Les argiles organophiles sont choisies en fonction de la nature chimique de chacune des matrices polyme`res. Les nanocomposites pre´pare´s a`partir de polyamide 6 pre´sentent une structure exfolie´e et des proprie´te´s barrie`res ame´liore´es alors qu'une morphologie de type microcomposite ne conduisant aà ucune ame´lioration des proprie´te´s barrie`res est obtenue pour le syste`me PE/montmorillonite. Diffe´rents polye´thyle`nes modifie´s sont alors e´value´s en tant qu'agents compatibilisants pour les syste`mes PE. Les effets de la masse molaire, de la polarite´et de la fraction massique d'agent compatibilisant sur la dispersion des charges et sur les proprie´te´s barrie`res sont e´tudie´s. Un taux massique d'agent compatibilisant e´gal a`4 fois celui des charges s'ave`re eˆtre optimal pour l'ensemble des agents compatibilisants. Par ailleurs, la masse molaire des agents compatibilisants joue un roˆle primordial sur l'e´tat de dispersion des charges. Contrairement aux syste`mes PA, les proprie´te´s barrie`res des syste`mes PE ne sont pas directement relie´es a`l'e´tat de dispersion des charges mais de´pendent e´galement des interfaces charges/matrice. Les PE oxyde´s de faible masse molaire sont identifie´s comme des agents compatibilisants particulie`rement inte´ressants pour les proprie´te´s barrie`res et une optimisation pas a`pas des syste`mes est entreprise. Une combinaison de PE oxyde´de faible masse molaire et de PE greffe´anhydride male´ique de haute masse molaire conduisant a`diviser la perme´abilite´aux gaz du nanocomposite d'un facteur 2 par rapport a`la matrice PE s'ave`re particulie`rement inte´ressante.Abstract -Reinforcement of the Gas Barrier Properties of Polyethylene and Polyamide Through the Nanocomposite Approach: Key Factors and Limitations -In this study, polyamide 6 (PA6) and polyethylene (PE) nanocomposites were prepared from melt blending and a detailed characterization of the nanocomposite morphology and gas barrier properties was performed. The choice of the organoclay was adapted to each polymer matrix. Exfoliated morphology and improved gas transport Oil & Gas Science and Technology -Rev. IFP Energies nouvelles, Vol. 70 (2015), No. 2, pp. 237-249 Ó E. Picard et al., published by IFP Energies nouvelles, 2013 DOI: 10.2516 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.properties were obtained by melt mixing the polar PA6 matrix and the organoclay, whereas a microcomposite with poor...

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“…Beall et al reported that there are three regions around the clay platelets: the surface modifier region, the constrained polymer region, and the unconstrained polymer region. The surface modifier region is about 1-2 nm, while the constrained polymer region may extend 50-100 nm away from the clay platelet surface [43]. Therefore, DSC does not detect any traces of thermal transitions for the CLM with a complete exfoliated structure, where the motion of disk-like CL with a thickness of about 2 nm is completely constrained by MMT platelets (i.e., the DSC curves of the CLM with mass ratio +2:1 prepared at pH of 7 and 3).…”

Section: Glass Transition Behaviormentioning

confidence: 99%

Plane-interface-induced lignin-based nanosheets and its reinforcing effect on styrene-butadiene rubber

Jiang¹,

He²,

Yu³

et al. 2014

Express Polym. Lett.

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Abstract. Lignin was viewed as a spherical microgel in aqueous alkali. While spread out in a monolayer or adsorbed on a surface, lignin was made up of flexible, disk-like molecules with approximately the same thickness of 2 nm. According to this principle, we employed the lamina of montmorillonite (MMT) as a plane template to anchor cationic lignin (CL) on its two sides, resulting in the formation of CL-MMT hybrid materials (CLM). The isotherm adsorption behavior and structure characteristics of CLM were studied. The results showed that CLM was individually dispersed nanosheets with a thickness of about 5 nm when the mass ratio of CL to MMT is more than 2:1 and prepared at acidic or neutral pH. Compared to the cocoagulation of lignin and styrene-butadiene rubber (SBR), CLM obviously accelerated the coagulation rate, due to the reduction of surface activity of CL restricted by MMT. The nanoscale dispersion of CLM in SBR matrix significantly improved the tensile strength of CLM/SBR nanocomposites to 14.1 MPa by adding only 10 phr CLM and cardanol glycidyl ether (CGE) as compatibilizer. Dynamic mechanical analysis (DMA) showed that the glass transition temperature of SBR/CLM nanocomposites decreased with increasing CLM loading. Correspondingly, a special interfacial structure was proposed.

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Direct measurement of the constrained polymer region in polyamide/clay nanocomposites and the implications for gas diffusion

Cited by 148 publications

References 19 publications

Nanocomposites in Food Packaging – A Review

Nanocomposites in Food Packaging – A Review

Reinforcement of the Gas Barrier Properties of Polyethylene and Polyamide Through the Nanocomposite Approach: Key Factors and Limitations

Plane-interface-induced lignin-based nanosheets and its reinforcing effect on styrene-butadiene rubber

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