Literature on polymer composites

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  • Giant magnetic susceptibility enhancement in field-structured nanocomposites, James.E. Martin et al. (2008)
    TitleGiant magnetic susceptibility enhancement in field-structured nanocomposites
    AuthorsJames.E. Martin, E.L. Venturini, D.L. Huber
    PublicationJournal of Magnetism and Magnetic Materials
    VolumeIn Press, Accepted Manuscript
    Date18 April 2008
    AbstractWe demonstrate through experiment and simulation that when mono-domain Fe nanoparticles are formed into chains by the application of a magnetic field, the susceptibility of the resulting structure is greatly enhanced (11.4-fold) parallel to the particle chains, and is much larger than transverse to the chains. Simulations show that this significant enhancement is expected when the susceptibility of the individual particles approaches 5 in MKS units, and is due to the spontaneous magnetization of individual particle chains, which occurs because of the strong dipolar interactions. This large enhancement is only possible with nanoparticles, because demagnetization fields limit the susceptibility of a spherical multi-domain particle to 3 (MKS). Experimental confirmation of the large susceptibility enhancement is presented, and both the enhancement and the susceptibility anisotropy are found to agree with simulation. The specific susceptibility of the nanocomposite is 54 (MKS), which exceeds the highest value we have obtained for field-structured composites of multi-domain particles by a factor of four.
  • In-situ synthesis of poly(dimethylsiloxane)–gold nanoparticles composite films and its application in microfluidic systems, Q. Zhang et al. (2007)
    TitleIn-situ synthesis of poly(dimethylsiloxane)–gold nanoparticles composite films and its application in microfluidic systems
    AuthorsQ. Zhang, J. Xu, Y. Liu, H. Chen
    PublicationLab on a Chip
    DateNov, 2007
    AbstractWe presented a simple approach for in-situ synthesis of poly(dimethylsiloxane) (PDMS)–gold nanoparticles composite film based on the special characteristics of PDMS itself. It is an environmentally safe synthesis method without the requirement of additional reducing/stabilizing agents. The region where the resulting gold nanoparticles distribute (in the matrix or on the surface of the polymer) and the size of the nanoparticles, as well as the colour of the free-standing films, can be simply controlled by adjusting the ratio of curing agent and the PDMS monomer. The chemical and optical properties of these composite films were studied. Using such a method, gold nanoparticle micropatterns on PDMS surfaces can be performed. And based on the gold nanoparticles micropattern, further modification with antibodies, antigens, enzymes and other biomolecules can be achieved. To verify this ability, an immobilized glucose oxidase (GOx) reactor in microchannels was built and its performance was studied. The experiments have shown that the resulting composite film may have a lot of potential merits in protein immobilization, immunoassays and other biochemical analysis on PDMS microchips.
  • Doping nanoparticles into polymers and ceramics using ultrasound radiation, Aharon Gedanken (2007)
    TitleDoping nanoparticles into polymers and ceramics using ultrasound radiation
    AuthorAharon Gedanken
    PublicationUltrasonics Sonochemistry
    DateApril 2007
    AbstractIn materials science, sonochemistry is mostly used for the fabrication of nanomaterials, but it has also been used for the polymerization of monomers. The current review is aimed at introducing a new application of sonochemistry to materials science, i.e., the doping of nanoparticles into polymers and ceramic bodies. The introduction will present a short overview of sonochemistry, and will outline the advantages of sonochemistry as a tool for fabricating nanomaterials.
  • Novel highly elastic magnetic materials for dampers and seals: part II. Material behavior in a magnetic field, S. Abramchuk et al. (2007)
    TitleNovel highly elastic magnetic materials for dampers and seals: part II. Material behavior in a magnetic field
    AuthorsS. Abramchuk, E. Kramarenko, D. Grishin, G. Stepanov, L. V. Nikitin, G. Filipcsei, A. R. Khokhlov, M. Zr�nyi
    PublicationPolymers for Advanced Technologies
    AbstractThe combination of polymers with magnetic particles displays novel and often enhanced properties compared to the traditional materials. They can open up possibilities for new technological applications. The magnetic field sensitive elastomers represent a new type of composites consisting of small particles, usually from nanometer range to micron range, dispersed in a highly elastic polymeric matrix. In this paper, we show that in the presence of built-in magnetic particles it is possible to tune the elastic modulus by an external magnetic field. We propose a phenomenological equation to describe the effect of the external magnetic field on the elastic modulus. We demonstrate the engineering potential of new materials on the examples of two devices. The first one is a new type of seals fundamentally different from those used before. In the simplest case, the sealing assembly includes a magnetoelastic strip and a permanent magnet. They attract due to the magnetic forces. This ensures that due to high elasticity of the proposed composites and good adhesion properties, the strip of magnetoelastic will adopt the shape of the surface to be sealed, this fact leading to an excellent sealing. Another straightforward application of the magnetic composites is based on their magnetic field dependent elastic modulus. Namely, we demonstrate in this paper the possible application of these materials as adjustable vibration dampers. Copyright � 2007 John Wiley & Sons, Ltd
  • Fabrication and Characterization of Nickel Nanowire Polymer Composites, H. Denver et al. (2007)
    TitleFabrication and Characterization of Nickel Nanowire Polymer Composites
    AuthorsH. Denver, J. Hong, D. Borca-Tasciuc
    PublisherMaterials Research Society
    AbstractMagnetic polymers are multi-functional composites emerging as a new category of smart materials. This work focuses on fabrication and characterization of magnetic polymer nanocomposites based on polydimethylsiloxane (PDMS) elastomer matrix. The magnetic fillers are commercially available Ni nanoparticles and respectively in-house fabricated Ni nanowires. Synthesis of Ni nanowires is achieved by electroless deposition inside nanoporous anodic alumina templates. After template removal, the nanowires are coated with 1-Octodecanethiol surfactant and mixed with PDMS using a FlackTek SpeedMixer. In parallel, nanoparticles are mixed with PDMS, without undergoing surfactant coating. Both composites are evaluated by scanning electron microscope (SEM) to determine dispersion uniformity. Mechanical properties are resolved by tensile tests performed by an instron. Preliminary results suggest that surfactant addition enhances dispersion, while mechanical properties of the composites for up to 5 vol. % of added nickel remain close to that of the polymer matrix without filler.
  • Complete UV emission of ZnO nanoparticles in a PMMA matrix, Xi-Wen Du et al. (2006)
    TitleComplete UV emission of ZnO nanoparticles in a PMMA matrix
    AuthorsXi-Wen Du, Ying-Song Fu, Jing Sun, Xue Han, Jim Liu
    PublicationSemiconductor Science and Technology
    AbstractPreparation and photoluminescence (PL) properties of zinc oxide (ZnO) nanoparticles embedded in a lipophilic polymethyl methacrylate (PMMA) matrix are reported in detail with an unbalanced sol-gel route. A high-resolution transmission electron microscope (HRTEM) indicates that ZnO particles are highly crystallized, with a size of 5-6 nm and hexagonal wurtzite structure. During the sol-gel reaction, partial ester groups of R-COOCH3 in PMMA are hydrolyzed to form carboxylic ion groups, which chemisorb on the surface of ZnO nanoparticles to eliminate the defects; thus ZnO nanoparticles in the PMMA matrix exhibit complete ultraviolet (UV) emissions, while emissions in the visible region are fully quenched.
  • Electric and Magnetic Field-Structured Smart Composites, Zsolt Varga et al. (2005)
    TitleElectric and Magnetic Field-Structured Smart Composites
    AuthorsZsolt Varga, Genov�va Filipcsei, Andr�s Szil�gyi, Mikl�s Zr�nyi
    PublicationMacromolecular Symposia
    AbstractThe combination of polymers with nanomaterials displays novel and often enhanced properties compared to the traditional materials. They can open up possibilities for new technological applications. The electric- and magnetic- field-sensitive elastomers represent a new type of composites consisting of small particles, usually from nanometer range to micron range, dispersed in high elastic polymeric matrix. Coupling of electric and/or magnetic fields with elastic properties leads to a number of striking phenomena that are exhibited in response to impressed external fields.The ability of such materials to change their size and mechanical properties in a reversible manner has inherent interest, if for no other reason than the uniqueness having giant elastic response to polarization. The giant deformational effect, high elasticity, anisotropic properties, and quick response to either electric or magnetic fields open new opportunities for using such materials for various applications. Since electric and magnetic fields are convenient stimuli from the point of signal control, it is of great importance to develop and study such flexible, smart polymeric systems.
  • Polydimethylsiloxane-magnetite nanoparticle complexes and dispersions in polysiloxane carrier fluids, K.S. Wilson et al. (2005)
    TitlePolydimethylsiloxane-magnetite nanoparticle complexes and dispersions in polysiloxane carrier fluids
    Authors K.S. Wilson, J.D. Goff, J.S. Riffle, L.A. Harris, T.G. St.Pierre
    PublicationPolymers for Advanced Technologies
    AbstractDispersions of sterically stabilized magnetite nanoparticles in polydimethylsiloxane (PDMS) carrier fluids have been prepared for potential biomedical applications. Trivinylsiloxy-terminated PDMS was functionalized with mercaptoacetic acid or mercaptosuccinic acid to afford PDMS stabilizers containing either three or six carboxylic acid groups, respectively, at one chain-end. Magnetite nanoparticles were synthesized by a chemical co-precipitation reaction of FeCl2 and FeCl3 with hydroxide at pH 9-10. Subsequently, the PDMS stabilizers were adsorbed onto the magnetite nanoparticle surfaces via the carboxylate groups in an interfacial reaction at an acidic pH. The complexes were characterized with transmission electron microscopy to establish an average particle diameter of 7.4 ± SD 1.7 nm and approximately spherical shape. Complexes containing up to 67 wt% magnetite were prepared using these PDMS stabilizers, resulting in maximum saturation specific magnetizations of ?50 emu g-1. The polymer-magnetite nanoparticle complexes could be dispersed in PDMS oligomers to afford polysiloxane ferrofluids. Copyright © 2005 John Wiley & Sons, Ltd.
  • Magnetic, electrical and optical properties of metal-polymer nanocomposites, A.D. Pomogailo et al. (2005)
    TitleMagnetic, electrical and optical properties of metal-polymer nanocomposites
    AuthorsA.D. Pomogailo, V.N. Kestelman
    AbstractHighly dispersed nanoscale particles in polymer matrices are currently attracting great interest in many fields of chemistry, physics, and materials science. This book presents and analyzes the essential data on nanoscale metal clusters dispersed in, or chemically bonded with polymers. Special attention is paid to the in situ synthesis of the nanocomposites, their chemical interactions, and the size and distribution of the particles in the polymer matrix. Numerous novel nanocomposites are described with regard to their mechanical, electrophysical, optical, magnetic, catalytic, and biological properties. Their applications, present and future, are outlined. The book is addressed both to researchers who actively use these materials and to students entering this multidisciplinary field.
  • Composite elastic magnet films with hard magnetic feature, Weisong Wang et al. (2004)
    TitleComposite elastic magnet films with hard magnetic feature
    AuthorsWeisong Wang, Zhongmei Yao, Jackie C. Chen, Ji Fang
    PublicationJournal of Micromechanics and Microengineering
    AbstractHard magnetic materials with high remnant magnetic moment, Mr, have unique advantages that can achieve bi-directional (push-pull) movement in an external magnetic field. This paper presents the results on the fabrication and testing of novel composite elastic permanent magnet films. The microsize hard barium ferrite powder, NdFeB powder, and different silicone elastomers have been used to fabricate various large elongation hard magnetic films. Three different fabrication methods, screen-coating processing, moulding processing and squeegee-coating processing, have been investigated, and the squeegee-coating process was proven to be the most successful method. The uniform composite elastic permanent magnet films range from 40 µm to 216 µm in thickness have been successfully fabricated. These films were then magnetized in the thickness direction after fabrication. They exhibited permanent magnet behaviour; for instance, the film (0.640 mm3 in volume) made of polydimethyl siloxane (PDMS) and hard barium ferrite powders is measured to give a coercive force, Hc, of 3.24 × 105 A m[?]1 and Mr of 1.023 × 10[?]5 A m2, and the film (0.504 mm3 in volume) made of PDMS and NdFeB powders gives 1.55 × 105 A m[?]1 Hc and 8.081 × 10[?]5 A m2 Mr. These composite elastic permanent magnet films' mechanical properties, like Young's modulus and deflection force, have been evaluated. To validate the films' Young's modulus, a finite-element computer simulation (ANSYS®) is used and one film is chosen whose Young's modulus (16.60 MPa) is confirmed by the simulation results with ANSYS®. The large elongation composite elastic permanent magnet film provides an excellent diaphragm material, which plays an important role in the micropump or valve. The movement of the 126 µm thick film with 4.5 mm diameter made of PDMS and NdFeB powders has been tested in a 0.21 Tesla external magnetic field. It was proven to have large deflection of 125 µm.
  • Concepts for the incorporation of inorganic building blocks into organic polymers on a nanoscale, Guido Kickelbick (2003)
    TitleConcepts for the incorporation of inorganic building blocks into organic polymers on a nanoscale
    AuthorGuido Kickelbick
    PublicationProgress in Polymer Science
    DateJanuary 2003
    AbstractHybrid inorganic-organic materials are promising systems for a variety of applications due to their extraordinary properties based on the combination of the different building blocks. The combination of nanoscale inorganic moieties with organic polymers has a high potential for future applications and has therefore attracted a lot of attention during the last years. Since there are countless different combinations of the two moieties, there are also a large number of methodologies to combine them in one material. This review is written with the intention to give an overview of principal concepts of the preparation of such materials for different applications. It focuses on the chemical aspects of the incorporation of inorganic building blocks such as silica networks, porous materials, metals, etc. into an organic polymeric matrix.
  • Anisotropic magnetism in field-structured composites, James E. Martin et al. (2000)
    TitleAnisotropic magnetism in field-structured composites
    AuthorsJames E. Martin, Eugene Venturini, Judy Odinek, Robert A. Anderson
    PublicationPhysical Review E
    DateMarch 2000
  • Model of magnetorheological elastomers, L. C. Davis (1999)
    TitleModel of magnetorheological elastomers
    AuthorL. C. Davis
    PublicationJournal of Applied Physics
    DateMarch 15, 1999
  • Electron behavior and magnetic properties of polymer nanocomposites, D. Y. Godovski (1995)
    TitleElectron behavior and magnetic properties of polymer nanocomposites
    AuthorD. Y. Godovski
    PublisherSpringer Berlin / Heidelberg
    AbstractIn this review article, an attempt has been made to describe the relatively new class of composite systems, polymer nanocomposites. The study of nanocomposites is determined by a number of anomalous properties, exhibited by both the nanoparticles themselves and the systems of such objects immersed in a polymer matrix. The anomalous character of nanoparticle properties is determined by their medium position between continuous bulk and single atoms. Such particles between 10 to 1000 Å sometimes exhibit a number of quantum size effects that determine anomalous optical and magnetic properties. The cooperative effects of composites with interacting nanoparticles is another distinctive feature of such systems. These effects occur at the so-called percolation threshold, where the particles begin having contact with one another, whereby the interparticle contacts increase with the increase in their number. The electronic, optical and magnetic properties of composites, which change with the changes in cluster structure, are also discussed in this review.
  • Magnetroviscoelastic behavior of composite gels, Tohru Shiga et al. (1995)
    TitleMagnetroviscoelastic behavior of composite gels
    AuthorsTohru Shiga, Akane Okada, Toshio Kurauchi
    PublicationJournal of Applied Polymer Science
    AbstractDynamic viscoelasticity of silicone gels having many lines of dispersed iron particles under the influence of external magnetic fields was studied. The particulate composite enhanced its elastic modulus by action of magnetic fields. The magnetroviscoelastic behavior was caused by the cohesive forces between magnetically polarized particles and was analyzed using a simple model of induced dipole-induced dipole interactions. The presented results provide insight into the relationship between macroscopic viscoelastic behavior of the composite gels and the microscopic bondings between dispersed particles. � 1995 John Wiley & Sons, Inc