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S. S. Sternstein

Bio: S. S. Sternstein is an academic researcher from Rensselaer Polytechnic Institute. The author has contributed to research in topics: Fumed silica & Vinyl acetate. The author has an hindex of 4, co-authored 4 publications receiving 1285 citations.

Papers
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Journal ArticleDOI
08 Jul 2010-Polymer
TL;DR: In this paper, the state of the art regarding the understanding and prediction of the macro-scale properties of polymers reinforced with nanometer-sized solid inclusions over a wide temperature range is established.

778 citations

Journal ArticleDOI
TL;DR: In this article, composites of fumed silica with various surface treatments and matrices of poly(vinyl acetate) of different molecular weights as well as a copolymer matrix of vinyl acetate and vinyl alcohol are reported.
Abstract: Nonlinear viscoelastic properties are reported for composites of fumed silica with various surface treatments and matrices of poly(vinyl acetate) of different molecular weights as well as a copolymer matrix of vinyl acetate and vinyl alcohol. Data above the glass transition temperature are reported here. The increase in the composite storage and loss moduli measured at low strains, and their relative rates of decrease with strain, are found to depend on filler surface treatment. The nonlinear behavior of the loss factor with strain is dramatically altered by filler treatment and quite revealing as to the likely mechanism causing the nonlinearity. In addition, the relative reinforcement and the degree of nonlinearity are found to be the highest for the lowest molecular weight matrices. The effect of copolymer substitution for the homopolymer matrix is equivalent to an increase in molecular weight. The primary underlying mechanism for reinforcement and nonlinear behavior appears to be the filler−matrix inte...

494 citations

Journal ArticleDOI
TL;DR: In this article, the role of the mean distance between these nanofillers on the overall conformation of polymer chains and, more importantly, on the statistics of bridges, dangling ends, loops, and trains was investigated.
Abstract: Lattice Monte Carlo simulations were performed on monodisperse polymer melts, with DP's ranging from 100 to 400, filled with nanoparticles of sizes comparable to the chain Rg. We critically study the role of the mean distance between these nanofillers on the overall conformation of polymer chains and, more importantly, on the statistics of bridges, dangling ends, loops, and trains. We are motivated to study these issues since it has been suggested that the mechanical behavior of nanocomposites result from the formation of a long-lived transient filler network mediated by the chains. Further, the experimentally observed increase in low frequency, low strain amplitude elastic modulus on the addition of filler is attributed to strongly stretched bridge segments. We find that the overall chain statistics remain Gaussian regardless of filler loading (up to 27 vol %). Short bridges, loops, and tails are strongly stretched, but in a manner that is quantitatively equivalent to the statistics of subchains in a mel...

100 citations

Journal ArticleDOI
10 Sep 2007-Polymer
TL;DR: In this article, small-angle scattering (SAS) experiments were carried out on nanocomposites of polyvinyl acetate (PVAc) and fumed silica nanoparticles with different surface areas and chemical treatment, in the wave-vector (Q ) range: 0.0002-1.A −1.

13 citations


Cited by
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Journal ArticleDOI
07 Jan 2011-Polymer
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.

2,782 citations

Journal ArticleDOI
TL;DR: Characterization and Properties 3928 8.2.1.
Abstract: 5. In Situ Polymerization 3907 5.1. General Polymerization 3907 5.2. Photopolymerization 3910 5.3. Surface-Initiated Polymerization 3912 5.4. Other Methods 3913 6. Colloidal Nanocomposites 3913 6.1. Sol-Gel Process 3914 6.2. In Situ Polymerization 3916 6.2.1. Emulsion Polymerization 3917 6.2.2. Emulsifier-Free Emulsion Polymerization 3919 6.2.3. Miniemulsion Polymerization 3920 6.2.4. Dispersion Polymerization 3921 6.2.5. Other Polymerization Methods 3923 6.2.6. Conducting Nanocomposites 3924 6.3. Self Assembly 3926 7. Other Preparative Methods 3926 8. Characterization and Properties 3928 8.1. Chemical Structure 3928 8.2. Microstructure and Morphology 3929 8.3. Mechanical Properties 3933 8.3.1. Tensile, Impact, and Flexural Properties 3933 8.3.2. Hardness 3936 8.3.3. Fracture Toughness 3937 8.3.4. Friction and Wear Properties 3937 8.4. Thermal Properties 3938 8.5. Flame-Retardant Properties 3941 8.6. Optical Properties 3942 8.7. Gas Transport Properties 3943 8.8. Rheological Properties 3945 8.9. Electrical Properties 3945 8.10. Other Characterization Techniques 3946 9. Applications 3947 9.1. Coatings 3947 9.2. Proton Exchange Membranes 3948 9.3. Pervaporation Membranes 3948 9.4. Encapsulation of Organic Light-Emitting Devices 3948

1,915 citations

Journal ArticleDOI
TL;DR: In this paper, a multi-core model with the far-distance effect, which is closely related to an "interaction zones", has been proposed from consideration of mesoscopic analysis of electrical and chemical structures of an existing interface with finite thickness.
Abstract: Polymer nanocomposites possess promising high performances as engineering materials, if they are prepared and fabricated properly. Some work has been recently done on such polymer nanocomposites as dielectrics and electrical insulation. This was reviewed in 2004 based on the literatures published up to 2003. New significant findings have been added since then. Furthermore, a multi-core model with the far-distance effect, which is closely related to an "interaction zones", has been proposed from consideration of mesoscopic analysis of electrical and chemical structures of an existing interface with finite thickness. It is speculatively examined in the paper how the model works for various properties and phenomena already found in nanocomposites as dielectrics focusing on electrical characteristics, resistance to high voltage environment, and thermal properties.

903 citations

Journal ArticleDOI
TL;DR: In this article, the future of mesoscopic properties of nanocomposite polymers is discussed, and several interesting results to indicate the foreseeable future have been revealed, some of which are described on materials and processing, together with basic concepts and future direction.
Abstract: Polymer nanocomposites are defined as polymers in which small amounts of nanometer size fillers are homogeneously dispersed by only several weight percentages. Addition of just a few weight percent of the nanofillers has profound impact on the physical, chemical, mechanical and electrical properties of polymers. Such change is often favorable for engineering purpose. This nanocomposite technology has emerged from the field of engineering plastics, and potentially expanded its application to structural materials, coatings, and packaging to medical/biomedical products, and electronic and photonic devices. Recently these 'hi-tech' materials with excellent properties have begun to attract research people in the field of dielectrics and electrical insulation. Since new properties are brought about from the interactions of nanofillers with polymer matrices, mesoscopic properties are expected to come out, which would be interesting to both scientists and engineers. Improved characteristics are. expected as dielectrics and electrical insulation. Several interesting results to indicate the foreseeable future have been revealed, some of which are described on materials and processing in the paper together with basic concepts and future direction.

889 citations

Journal ArticleDOI
TL;DR: In this paper, the incorporation of silica nanoparticles into polyethylene increased the breakdown strength and voltage endurance significantly compared to the inclusion of micron scale fillers, and showed a decrease in dielectric permittivity for the nanocomposite over the base polymer.
Abstract: The incorporation of silica nanoparticles into polyethylene increased the breakdown strength and voltage endurance significantly compared to the incorporation of micron scale fillers. In addition, dielectric spectroscopy showed a decrease in dielectric permittivity for the nanocomposite over the base polymer, and changes in the space charge distribution and dynamics have been documented. The most significant difference between micron scale and nanoscale fillers is the tremendous increase in interfacial area in nanocomposites. Because the interfacial region (interaction zone) is likely to be pivotal in controlling properties, the bonding between the silica and polyethylene was characterized using Fourier transformed infrared (FTTR) spectroscopy, electron paramagnetic resonance (EPR), and x-ray photoelectron spectroscopy (XPS). The picture which is emerging suggests that the enhanced interfacial zone, in addition to particle-polymer bonding, plays a very important role in determining the dielectric behavior of nanocomposites.

817 citations