Adsorption of Multiblock and Random Copolymer on a Solid Surface: Critical Behavior and Phase Diagram

• Published in: Macromolecules Vol. 41; no. 8; pp. 2920 - 2930
• Main Authors: Bhattacharya, S, Hsu, H.-P, Milchev, A, Rostiashvili, V. G, Vilgis, T. A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 22-04-2008
• Subjects: Applied sciences; Exact sciences and technology; Organic polymers; Physicochemistry of polymers; Properties and characterization; Surface properties; Plane surface; Random copolymer; Monte Carlo method; Computer simulation; Liquid solid adsorption; Multiblock copolymer; Phase diagram; Lattice model; Theoretical study; Critical point; Comparative study
• ISSN: 0024-9297; 1520-5835
• DOI: 10.1021/ma702608j

The adsorption of a single multiblock AB copolymer on a solid planar substrate is investigated by means of computer simulations and scaling analysis. It is shown that the problem can be mapped onto an effective homopolymer adsorption problem. In particular, we discuss how the critical adsorption energy and the fraction of adsorbed monomers depend on the block length M of sticking monomers A, and on the total length N of the polymer chains. Also the adsorption of the random copolymers is considered and found to be well described within the framework of the annealed approximation. For a better test of our theoretical prediction, two different Monte Carlo (MC) simulation methods were employed: (a) off-lattice dynamic bead-spring model, based on the standard Metropolis algorithm (MA), and (b) coarse-grained lattice model using the pruned-enriched Rosenbluth method (PERM) which enables tests for very long chains. The findings of both methods are fully consistent and in good agreement with theoretical predictions.