Monte Carlo Simulation of Adsorption of Di-Block Copolymers

1988 ◽  
Vol 140 ◽  
Author(s):  
Wan Y. Shih ◽  
Wei-Heng Shill ◽  
Ilhan A. Aksay

AbstractIn this paper we are concerned with the morphology of the polymers adsorbedon surfaces, in particular di-block copolymers. Our work is motivated by the experimental findings of Fladziioannou et al. [1] on the steric forces between two adsorbed layers of di-block poly(vinyl-2-pyridine)\ polystyrene (PV2P\ PS) copolymer on mica surfaces. The PV2P block binds strongly on the mica surfaces and the PS block extends into thesolvent toluene (good solvent for PS). Hadziiouannou et al. found that the repulsive forces between the two surfaces start at a distance 1) larger than 10 times the radius of gyration RG of a free P' in toluene. Furthermore, the starting distance D increases with increasing degree of polymerization N of PS in a fashion I) ~ Na with a close to I. We,tudy the adsorption of di-block copolymer with Monte Carlo simulations. The Monte Carlo simulations are especially powerful in dealing with kinetics which is important in systems where hysteresis is observed II1 and cannot be appropriately taken into account by analytical (or numerical) calculations based onequilibrium assumptions.

Author(s):  
Armin Bergermann ◽  
Martin French ◽  
Ronald Redmer

The miscibility gap in H2–H2O mixtures is investigated by conducting Gibbs-ensemble Monte Carlo simulations. Our results indicate that H2–H2O immiscibility regions may have a significant impact on the structure and evolution of ice giant planets.


1996 ◽  
Vol 118 (2) ◽  
pp. 388-393 ◽  
Author(s):  
J. Zaworski ◽  
J. R. Welty ◽  
B. J. Palmer ◽  
M. K. Drost

The spatial distribution of light through a rectangular gap bounded by highly reflective, diffuse surfaces was measured and compared with the results of Monte Carlo simulations. Incorporating radiant properties for real surfaces into a Monte Carlo code was seen to be a significant problem; a number of techniques for accomplishing this are discussed. Independent results are reported for measured values of the bidirectional reflectance distribution function over incident polar angles from 0 to 90 deg for a semidiffuse surface treatment (Krylon™ flat white spray paint). The inclusion of this information into a Monte Carlo simulation yielded various levels of agreement with experimental results. The poorest agreement occurred when the incident radiation was at a grazing angle with respect to the surface and the reflectance was nearly specular.


2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
M. S. Mayeed ◽  
T. Kato

Applying the reptation algorithm to a simplified perfluoropolyether Z off-lattice polymer model an NVT Monte Carlo simulation has been performed. Bulk condition has been simulated first to compare the average radius of gyration with the bulk experimental results. Then the model is tested for its ability to describe dynamics. After this, it is applied to observe the replenishment of nanoscale ultrathin liquid films on solid flat carbon surfaces. The replenishment rate for trenches of different widths (8, 12, and 16 nms for several molecular weights) between two films of perfluoropolyether Z from the Monte Carlo simulation is compared to that obtained solving the diffusion equation using the experimental diffusion coefficients of Ma et al. (1999), with room condition in both cases. Replenishment per Monte Carlo cycle seems to be a constant multiple of replenishment per second at least up to 2 nm replenished film thickness of the trenches over the carbon surface. Considerable good agreement has been achieved here between the experimental results and the dynamics of molecules using reptation moves in the ultrathin liquid films on solid surfaces.


2018 ◽  
Vol 27 (4) ◽  
pp. 1800012 ◽  
Author(s):  
Roser Sabater i Serra ◽  
Constantino Torregrosa Cabanilles ◽  
José María Meseguer Dueñas ◽  
José Luis Gómez Ribelles ◽  
José Molina-Mateo

2005 ◽  
Vol 38 (20) ◽  
pp. 8522-8531 ◽  
Author(s):  
Francisco J. Martínez-Veracoechea ◽  
Fernando A. Escobedo

Sign in / Sign up

Export Citation Format

Share Document