Block copolymer nanocomposites

G. Wimsberger and G.D. Stucky, Microring Lasing from Dye-doped Silica/Block Copolymer Nanocomposites. Chem. Mater., 2000, 12, 2525-2527. 

M. R. Bockstaller, R. A. Mickievltch, and E. L. Thomas, Block copolymer nanocomposites perspectives for tailored functional materials, Adv. Mater., 17,1331-1349 (2005). 

BockstaUer, M. R., Mickiewicz, R. A., and Thomas, E. L. 2005. Block copolymer nanocomposites Perspectives for tailored functional materials. Advanced Materials 17 1331-1349 Fischer, H. 2003. Polymer nanocomposites From fimdamental research to specific applications. Materials Science and Engineering C 23 763-772. 

In the following Section 3.1.1, the morphology is discussed for block copolymer nanostructures via self-assembly (Section 3.1.1.1), in dependence on the chain architecture (Section 3.1.1.2), for blends of block copolymers with a constituent homopolymer (Section 3.1.1.3), for processing-induced influences (Section 3.1.1.4), and for block copolymer nanocomposites (Section 3.1.1.5). Section 3.1.2 gives an overview of nano- and micromechanical deformation effects. 

Wirnsberger G., Stucky G.D. Microring lasing from dye-doped silica/block copolymer nanocomposites. Chem. Mater. 2000 12 2525-2527... 

Hillmyer, M.A., Lipic, P.M., Hajduk, D.A., Almdal, K., and Bates, F.S. (1997) Self assembly and polymerization of epoxy resin amphiphilic block copolymer nanocomposites. J. Am. Chem. Soc.,... 

Keywords loss tangent mechanical relaxation block copolymers nanocomposites carbon nanotubes... 

Particle distributions in a block copolymer nanocomposite. Macromolecules, 41,1853-60. 

Ha YH, Kwon Y, Breiner T, Chan EP, Tzianetopoulou T, Cohen RE, Boyce MC, Thomas EL (2005) An orientationally ordered hierarchical exfoliated clay-block copolymer nanocomposite. Macromolecule 38 5170-5179... 

Block-Copolymers, Nanocomposites, Organic/Inorganic Hybrids, Polymethylenes... 

Tamil S.S., Tomokatsu H., Masayuki N., and Martin M. Block copolymer mediated synthesis of gold quantum dots and novel gold-polypyrole nanocomposites, J. Phys. Chem., 103, 7441, 1999. 

Fig. 68 Comparison of temperature-dependent intensity of first-order Bragg peak for bare matrix copolymer (A) containing 0.5 wt% nanocomposites with plate-like (V), spherical (o) and rod-like ( ) geometry. Data are vertically shifted for clarity. Inset dependence of ODT temperature on dimensionality of fillers (spherical 0, rod-like 1, plate-like 2). Vertical bars width of phase transition region. Pure block copolymer is denoted matrix . From [215]. Copyright 2003 American Chemical Society...

To date, the melt state linear dynamic oscillatory shear properties of various kinds of nanocomposites have been examined for a wide range of polymer matrices including Nylon 6 with various matrix molecular weights [34], polystyrene (PS) [35], PS-polyisoprene (PI) block copolymers [36,37], poly(e-caprolactone) (PCL) [38], PLA [39,40], PBS [30,41], and so on [42],... 

Nylon blends, dyeing, 9 204 Nylon block copolymer, 19 762 Nylon carpet fibers, stain-resistant, 19 764 Nylon-clay nanocomposites, 11 313-314 Nylon extrusion, temperatures for, 19 789t Nylon feed yarns, spin-oriented, 19 752 Nylon fiber(s), 24 61 production of, 19 740 world production of, 19 7654 Nylon fiber surfaces, grafting of polymers on, 19 763-764... 

We measured the electrical conductivity of Pt-C nanocomposites using two-point measurements. In a representative example the NP-polymer hybrid had a conductivity of 2.5 mS cm-1, which increased to 400 S cm-1 upon pyrolysis. Despite the presence of carbon, to the best of our knowledge this value represented the highest electrical conductivity yet measured for ordered mesoporous materials derived from block copolymers. This discovery creates a potential pathway to a new class of ordered mesoporous metals made from nanoparticles of different elements and/or distinct compositions. Such nano-heterogeneous mesoporous metals may have a range of exceptional electrical, optical, and catalytic properties. 

Of course, nanocomposites are not the only area where mesoscale theories are being used to predict nanostructure and morphology. Other applications include—but are not limited to—block copolymer-based materials, surfactant and lipid liquid crystalline phases, micro-encapsulation of drugs and other actives, and phase behavior of polymer blends and solutions. In all these areas, mesoscale models are utilized to describe—qualitatively and often semi-quantitatively—how the structure of each component and the overall formulation influence the formation of the nanoscale morphology. 

On a global scale, the linear viscoelastic behavior of the polymer chains in the nanocomposites, as detected by conventional rheometry, is dramatically altered when the chains are tethered to the surface of the silicate or are in close proximity to the silicate layers as in intercalated nanocomposites. Some of these systems show close analogies to other intrinsically anisotropic materials such as block copolymers and smectic liquid crystalline polymers and provide model systems to understand the dynamics of polymer brushes. Finally, the polymer melt-brushes exhibit intriguing non-linear viscoelastic behavior, which shows strainhardening with a characteric critical strain amplitude that is only a function of the interlayer distance. These results provide complementary information to that obtained for solution brushes using the SFA, and are attributed to chain stretching associated with the space-filling requirements of a melt brush. 

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