Box size study: snapshots of Sel[1.0]-1.0 nanocomposite system started from disordered melts with different box sizes at . of cubic box, of diblock copolymer chains with five beads and five beads, density is fixed at 0.85 and all systems have 10% selective particles. Similar studies were done for all systems at various shear rates. Block A is shown in green, block B is shown in blue, and NPs are shown in red.
Orientation order parameter as a function of time at for Sel[1.0]-1.0, NonSel-1.0 and pure BCP systems.
Symmetric diblock copolymers mixed with selective nanoparticles (Sel[1.0]-1.0). (a) Snapshot from a MD simulation with . The block that is attracted to the nanoparticles is shown in blue, the other block is shown in green and the nanoparticles are shown in red. Concentration profiles of (b) the two copolymer blocks along with the profile of the selective particles where . (c) Concentration profiles of the particles at various shear rates as shown in the legend. The peaks become sharper with increasing shear rate. length.
NP concentration profiles at different shear rates for (a) Sel[0.9]-1.0 and (b) Sel[1.0]-1.5, and (c) NP concentration profiles of different particle diameters for selective particle systems at .
Symmetric diblock copolymers mixed with nonselective nanoparticles (NonSel-1.0). (a) Snapshot from a MD simulation with . One of the blocks is not shown for the sake of clarity, and the nanoparticles are shown in red. Concentration profiles of (b) the two copolymer blocks along with the profile of the nonselective particles where . In this case, the particles are equally attracted to both monomers. (c) Concentration profiles of the particles at various shear rates as shown in the legend. Shear has no significant effect on non selective nanoparticle concentration profiles. length.
Snapshots of symmetric diblock copolymers at 0, (b) 0.001 (parallel), and (c) critical shear rate (perpendicular), where orientation flip takes place. Green is block A and blue is block B.
Log-log plots of the calculated shear viscosity vs imposed shear rate for pure copolymer, copolymer with selective and nonselective nanoparticles.
Normalized root mean squared end to end distances of polymer chains for Sel[1.0]-1.0, NonSel-1.0 and pure BCP systems in the (a) and (b) directions. The axis is normalized using end to end distance in the direction at shear .
Snapshots of nanocomposites with (left) Sel[1.0]-1.0 NPs at (parallel) and critical shear rate (perpendicular) and (right) NonSel-1.0 NPs at (parallel) and critical shear rate, (perpendicular). Perpendicular morphologies are shown at respective critical shear rates where a transition from parallel to perpendicular lamellar takes place. For nonselective particle system, one of the blocks is not shown for the sake of clarity and particles are shown in red.
Concentration profiles of the -block chain end for different shear rates for (a) pure BCP and (b) Sel[1.0]-1.0 nanocomposite system of selective NPs.
Summary of interactions between the nanoparticles and the and monomers of the diblock copolymer.
Simulation parameters. The values in MD units are understood to be multiplied by the appropriate combinations of three independent fundamental units of length, mass and energy (Ref. 26).
Summary of all different types of nanoparticles used in this work.
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