Journal ArticleDOI
Quantitative equivalence between polymer nanocomposites and thin polymer films
Amitabh Bansal,Amitabh Bansal,Hoichang Yang,Hoichang Yang,Chunzhao Li,Kilwon Cho,Brian C. Benicewicz,Sanat K. Kumar,Linda S. Schadler +8 more
TLDR
The thermomechanical properties of ‘polymer nanocomposites’ are quantitatively equivalent to the well-documented case of planar polymer films and it is conjecture that the glass-transition process requires that the interphase regions surrounding different particles interact.Abstract:
The thermomechanical responses of polymers, which provide limitations to their practical use, are favourably altered by the addition of trace amounts of a nanofiller. However, the resulting changes in polymer properties are poorly understood, primarily due to the non-uniform spatial distribution of nanoparticles. Here we show that the thermomechanical properties of ‘polymer nanocomposites’ are quantitatively equivalent to the well-documented case of planar polymer films. We quantify this equivalence by drawing a direct analogy between film thickness and an appropriate experimental interparticle spacing. We show that the changes in glass-transition temperature with decreasing interparticle spacing for two filler surface treatments are quantitatively equivalent to the corresponding thin-film data with a non-wetting and a wetting polymer–particle interface. Our results offer new insights into the role of confinement on the glass transition, and we conclude that the mere presence of regions of modified mobility in the vicinity of the particle surfaces, that is, a simple two-layer model, is insufficient to explain our results. Rather, we conjecture that the glass-transition process requires that the interphase regions surrounding different particles interact.read more
Citations
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Journal ArticleDOI
Functionalized graphene sheets for polymer nanocomposites
T. Ramanathan,Ahmed Abdala,Ahmed Abdala,Sasha Stankovich,Dmitriy A. Dikin,Margarita Herrera-Alonso,Richard D. Piner,Richard D. Piner,Douglas H. Adamson,Hannes C. Schniepp,Xinqi Chen,Rodney S. Ruoff,Rodney S. Ruoff,SonBinh T. Nguyen,Ilhan A. Aksay,Robert K. Prud'homme,L. C. Brinson +16 more
TL;DR: Modulus, ultimate strength and thermal stability follow a similar trend, with values for functionalized graphene sheet- poly(methyl methacrylate) rivaling those for single-walled carbon nanotube-poly(methyl methamphetamine) composites.
Journal ArticleDOI
Graphene-based polymer nanocomposites
TL;DR: A survey of the literature on polymer nanocomposites with graphene-based fillers including recent work using graphite nanoplatelet fillers is presented in this article, along with methods for dispersing these materials in various polymer matrices.
Journal ArticleDOI
Structural and mechanical properties of polymer nanocomposites
TL;DR: In this paper, a review of the processing, structure, and mechanical properties of polymer nanocomposites reinforced with respective layered silicates, ceramic nanoparticles and carbon nanotubes is presented.
Journal ArticleDOI
Covalent polymer functionalization of graphene nanosheets and mechanical properties of composites
TL;DR: In this paper, the initiator molecules were covalently bonded to the graphene surface via a diazonium addition and the succeeding atom transfer radical polymerization linked polystyrene chains (82 wt% grafting efficiency).
Journal ArticleDOI
Anisotropic self-assembly of spherical polymer-grafted nanoparticles
Pinar Akcora,Hongjun Liu,Sanat K. Kumar,Joseph Moll,Yu Li,Brian C. Benicewicz,Linda S. Schadler,Devrim Acehan,Athanassios Z. Panagiotopoulos,Victor Pryamitsyn,Venkat Ganesan,Jan Ilavsky,Pappanan Thiyagarajan,Ralph H. Colby,Jack F. Douglas +14 more
TL;DR: It is demonstrated that spherical nanoparticles uniformly grafted with macromolecules ('nanoparticle amphiphiles') robustly self-assemble into a variety of anisotropic superstructures when they are dispersed in the corresponding homopolymer matrix.
References
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Journal ArticleDOI
Size-Dependent Depression of the Glass Transition Temperature in Polymer Films
TL;DR: In this article, the glass transition temperature of thin polystyrene films has been measured as a function of film thickness, and it was found that the transition decreases in temperature as the thickness of the film is reduced.
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The distribution of glass-transition temperatures in nanoscopically confined glass formers
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Journal ArticleDOI
Effect of Free Surfaces on the Glass Transition Temperature of Thin Polymer Films.
TL;DR: The concept of cooperative rearrangement was introduced in an attempt to unify these two views of the glass transition by demonstrating that such cooperativity, coupled with a thermodynamic glass transition, resulted naturally insystem dynamics such as those described by the WLFequation for temperatures near freezing.
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Structure and Dynamics of Polymer-Layered Silicate Nanocomposites
TL;DR: In this article, the static and dynamic properties of polymer-layered silicate nanocomposites are discussed in the context of polymers in confined media, and both the local and global dynamics of the polymer in the hybrids are dramatically different from those in the bulk.
Journal ArticleDOI
The glass transition in thin polymer films
TL;DR: In this article, a detailed account of important recent developments in the rapidly evolving area of glass transitions in thin polymer films is presented. But the case of polymer films supported by substrates, and a definite experimental consensus exists.