Effect of Orientational Specificity of Complexation on the Behavior of Supramolecular Polymers: Theory and Simulation

Abstract

Using Monte Carlo simulations we study the association of flexible oligomers terminated by a donor and an acceptor group capable of orientationally specific reversible bonding. On the basis of simulation results, we have obtained equilibrium constants for chain growth and ring closure. These constants were employed in an analytical model, which reproduces the large-scale simulation results very well. We also propose an analytical approach which can be used to analyze experimental data or make predictions of molecular weight, chain/ring distributions, etc., which are hard to obtain experimentally. Our simulation and analytical results show that an increase of orientational specificity of reversible bonding decreases the degree of association and molecular weight and leads to the suppression of small rings. As a result the ring−chain crossover concentration (i.e., the concentration at which the number of reversible bonds in chains and rings coincide) decreases and exhibits a maximum as a function of oligome...