ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCoil-globule type transitions in polymers. 1. Collapse of layers grafted polymer chainsE. B. Zhulina, O. V. Borisov, A. Pryamitsyn, and T. M. BirshteinCite this: Macromolecules 1991, 24, 1, 140–149Publication Date (Print):January 1991Publication History Published online1 May 2002Published inissue 1 January 1991https://pubs.acs.org/doi/10.1021/ma00001a023https://doi.org/10.1021/ma00001a023research-articleACS PublicationsRequest reuse...

We present a self-consistent field theory model for the self-assembly behavior of rod-coil block copolymers. The orientational interactions between rods were modeled through Maier-Saupe interaction, while enthalpic and coils standard Flory-Huggins approach. outline "real-space" numerical approach to solve equations such A major focus our work is upon nonlamellar phases observed in experiments on polymers. To develop physical understanding these their regimes occurrence, we compute...

We use computer simulations to study the mechanisms governing linear viscoelasticity behavior of composites spherical nanofillers dispersed in polymer melt matrices. Our results suggest that particles can influence viscoelastic properties system by a variety different mechanisms. On one hand, particle-induced effects on dynamics segments modify relaxation spectrum polymers. Second, particle jamming lead slow relaxations and substantial enhancements elasticity. Finally, our strain field...

We review some recent research developments in coarse-grained modeling based on mean-field approaches of the equilibrium dispersion and structure polymer nanoparticle composites. focus three issues: (i) phase behavior particles homopolymer matrices; (ii) mixtures homopolymers with grafted nanoparticles; (iii) self-assembly organization nanoparticles block copolymer matrices. In each these topics, we highlight that dispersability resulting suspension may exhibit far more complexities than one...

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTCoil-globule type transitions in polymers. 2. Theory of coil-globule transition linear macromoleculesT. M. Birshtein and V. A. PryamitsynCite this: Macromolecules 1991, 24, 7, 1554–1560Publication Date (Print):April 1, 1991Publication History Published online1 May 2002Published inissue 1 April 1991https://pubs.acs.org/doi/10.1021/ma00007a017https://doi.org/10.1021/ma00007a017research-articleACS PublicationsRequest reuse permissionsArticle...

We propose a combination of polymer field theory and off-lattice computer simulations to study polymer-bridged gelation in polymer-nanoparticle mixtures. use this method the structure gels formed attractive polymer-colloid systems. Our results indicate that such exhibit universal with fractal dimension ${d}_{f}\ensuremath{\approx}2.5$ characteristic random percolation. By mapping an affine-network model, enhancement elastic moduli is predicted follow critical exponent...

We present strong segregation approximation based analytical calculations and complementary computer simulation results on the ordering structural characteristics of block copolymer−nanoparticle mixtures. consider specifically case a symmetric copolymer organized in lamella phase, which is mixed with both selective nonselective nanoparticles. within quantifying density distribution nanoparticles influence upon thickness their elastic constants. The treated detail to account more accurately...

Highly asymmetric lamellar microdomains, such as those required for many lithographic line patterns, cannot be straightforwardly achieved by conventional block copolymer self-assembly. We present a conceptually new and versatile approach to produce highly morphologies the use of binary blends copolymers whose components are capable hydrogen bonding. first demonstrate our strategy in bulk systems complement experimental results observed transmission electron microscopy small-angle X-ray...

We study the polymer adsorption characteristics, pair-interaction potentials, and phase percolation behavior in nanoparticle-polymer mixtures. propose a "saturable" model to capture effect of finite surface saturation capacity for adsorption, use self-consistent field theory combination with McMillan-Mayer framework [McMillan, W. G., Jr.; Mayer, J. E. Chem. Phys. 1945, 13, 276] compute potentials. Our results demonstrate novel size effects that distinguish characteristics nanoparticles from...

We use a simple extension of the dissipative particle dynamics (DPD) model to address dynamical properties macrosolutes immersed in complex fluid solvents. In this approach, solvent particles are still represented as DPD particles, thereby retaining time and length scale advantages offered by approach. contrast, solute hard appropriate size. examine applicability simulation approach reproduce correct hydrodynamical characteristics mixture. Our results focus on equilibrium steady-state shear...

We propose a continuum model for the dynamics of particles in polymer matrices which encompasses arbitrary size ratios and particle. present analytical computer simulation results mobility viscosity suspension case unentangled melts. Our indicate strong dependencies particle upon polymer-particle much reduced intrinsic viscosities suspensions. These predictions rationalize some recent experimental observations on nanoparticles

We use a combination of polymer mean field theory and Monte Carlo simulations to study the polymer-bridged gelation, clustering behavior, elastic moduli polymer-nanoparticle mixtures. Polymer self-consistent is first numerically implemented quantify both induced interparticle interaction potentials conformational statistics chains between two spherical particles. Subsequently, formation structure nanoparticle gels are examined using simulations. Our results indicate universality in fractal...

Motivated by recent experiments, we examine within a percolation model whether there is quantitative equivalence in the glass transition temperatures of polymer thin films and nanocomposites. Our results indicate that, while qualitative behaviors these systems are similar, cannot be established general. However, propose phenomenological scaling collapse our which suggests simple framework may used to quantitatively predict properties

Recently, a number of experiments have demonstrated that addition ceramics with nanoscale dimensions can lead to substantial improvements in the low-temperature conductivity polymeric materials. However, origin such behaviors and, more generally, manner by which fillers impact ion mobilities remain unresolved. In this communication, we report results atomistic molecular dynamics simulations used multibody polarizable force fields study lithium diffusivities an amorphous poly(ethylene-oxide)...

Understanding the electrostatic interactions in ion-containing polymers is crucial to better design shape memory and ion-conducting membranes for multiple energy storage conversion applications. In molten polymers, dielectric permittivity low, generating strong ionic correlations that lead clustering of charges. Here, we investigate influence on nanostructure randomly charged (ionomers) using coarse-grained molecular dynamics simulations. Densely packed branched structures rich species are...

Both an asymptotic analytical analysis for chain length N → ∞ and exact numerical calculations finite lengths were applied to the structural properties of polyelectrolyte brushes under poor solvent conditions in a self-consistent field framework. We extend previous work on find evidence phase transition caused by internal separation brush upon decrease quality. In limit long chains, when local electroneutrality approximation is exact, we that continuous tends be second order. which employ...

Views Icon Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Twitter Facebook Reddit LinkedIn Tools Reprints and Permissions Cite Search Site Citation Victor Pryamitsyn, Venkat Ganesan; Mechanisms of steady-shear rheology in polymer-nanoparticle composites. J. Rheol. 1 September 2006; 50 (5): 655–683. https://doi.org/10.1122/1.2234483 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search...

We study the effective pair interaction potentials and resulting phase behavior, percolation transitions of nanorods dispersed in solutions adsorbing polymers. use polymer self-consistent-field theory conjunction with Derjaguin approximation to compute polymer-mediated orientation-dependent potential between cylindrical nanorods. A modified Flory a simple analytical model are used delineate different equilibrium phases onset for solutions. Our results suggest that topology diagram mixture...

We present a new model based on self-consistent field theory (SCFT) approach and complement it by strong segregation (SST) calculations to characterize the self-assembly behavior in side-chain liquid crystalline block copolymers. Our considers micromechanical representation of flexible coil−coil diblock copolymers, with rodlike units grafted one blocks. results which elucidate arising from interplay between copolymer microphase separation orientational ordering rod segments. determine...

Phase behavior of binary blends consisting high molecular weight polystyrene-block-poly(2-vinylpyridine) copolymer (PS-b-P2VP) and low polystyrene-block-poly(4-hydroxystyrene) (PS-b-PHS) was investigated by using small-angle X-ray scattering transmission electron microscopy. Both PS-b-P2VP PS-b-PHS exhibited lamellar microdomain over the entire experimental temperatures up to 300 °C. When fraction in blend less than 0.1, microdomains were maintained. However, with increasing amount PS-b-PHS,...

We consider the influence of sequence polydispersity upon phase behavior and interfacial characteristics gradient copolymers. By adapting algorithmic procedure proposed for random copolymers, we design sequences varying blockiness compositional polydispersities specified composition profiles Using so generated, studied dependence spinodals, behavior, properties copolymers as a function strengths sequences. demonstrate that interplay between overall can play significant role in determining...

We report on a theoretical study of the phase behavior polymer blends with hydrogen-bonding (HB) groups using mean-field approximation. The hydrogen bonds are modeled as saturable bonds. find parametric conditions for lower and upper critical solution temperatures (LCST UCST) eutectic HB blends. quantify miscibility, partial immiscibility evaluate applicability Flory–Huggins theory to polymers by analyzing composition dependence effective interaction parameter χeff. use self-consistent field...