Good- solvent to bad- solvent quenches at finite surface coverages are considered these correspond to established experimental protocols for adsorbing and then drying polymer sub-monolayers on surfaces. Solvent effects are explored by dialing in effective attractions between the monomer beads with decreasing solvent quality, the star polymers adopt more compact, globular structures. The latter three correspond to regimes predicted theoretically by Halperin and Joanny. Four conformational regimes are identified: a linear- polymer regime a two-dimensional star polymer regime a sombrero regime and a colloidal regime. The conformational properties of a single adsorbed star polymer in good- solvent conditions are considered as functions of the functionality (number of arms) f, the number of monomers per arm N, and the monomer-surface interaction energy ε s. The field is tilted the structures are only slightly perturbed, but once the anisotropyĮxceeds a critical value, completely new structures emerge.The behaviour of star polymers adsorbed on smooth surfaces is studied using coarse-grained bead-spring models and Langevin dynamics simulations. The anisotropy of the interparticle forces isĬontrolled by tilting the external magnetic field with respect to the plane. On energy landscapes, to investigate the ordered equilibrium structures formedīy binary mixtures of anisotropic dipolar particles confined on a plane, under the We have provided the firstĮxample of a scale-free network in amodel condensed-matter system.įinally, we use genetic algorithms, a method for efficiently searching for minima Networks, for example, in transportation systems, biochemical reactions, scientificĪnd movie-actor collaborations, and sexual contacts. Scale-free (power-law) behaviour is found in many important The disk diameterĭistribution was defined by a power-law with the aim of realizing a scale-free nearneighbour We investigated the neighbour distribution in a two-dimensional polydisperse harddiskįluid, corresponding physically to a colloidal monolayer. Examples of such particles are chemically synthesized polystyrene or silica particles. The simplest soft matter systems consist of spherical, rigid colloidal particles. Valuable insights on experimental findings. “soft colloids”) in the proximity of a surface, using Langevin dynamics simulations.Ī number of different measurements such as the height, radius of gyration, andĪsphericity of adsorbed stars with different number of arms, are shown to provide We explore the behaviour of the star polymers (which are like Structures are effectively considered as intermediate between those of colloids and Of these molecules led to the synthesis of a wide range of new materials. Linear chain is tethered to a small central core to forma single particle. Star polymers represent a special class of polymers, in which one end of each The surface, and the scaling of the filmheight with the strength of the polymer-surface Scaling laws such as the decay of the monomer density as a function of distance from On experimental observations, the simulation results support a number of predicted Type of distribution can be reproduced in the simulations, and rationalized on theīasis of the polymer structures prior to the quench. In the case of linear polymers, under certain experimentalĬonditions, a bimodal cluster distribution is observed. Surfaces, adsorbed from dilute solution following a good solvent-to-bad solvent TheĪim is to gain insight on atomic-forcemicroscopy images of polymer films on mica Of linear and star polymers on smooth surfaces are studied using coarse-grained,īead-springmolecular models and Langevin dynamics computer simulations. In this work, the adsorption and self assembly Intriguing and useful physical properties. Some of the most important examples of soft matter are polymers, which exhibit TheyĪre instead macromolecular aggregates, whose spatial extent lies in the domain 1 nm Of soft matter lies in the fact that they are not atomic or molecular in nature. The term “soft matter” applies to a variety of physical systems, such as liquids,Ĭolloids, polymers, foams, gels, and granular materials.
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