A simple and general approach for reversible condensation polymerization with cyclization

TL;DR

This paper introduces a recursive analytical approach to reversible condensation polymerization with cyclization, capable of handling various complex scenarios and validated by simulations, advancing the modeling of polymer systems.

Contribution

It presents a flexible, exact analytical framework for reversible condensation polymerization with cyclization, accommodating complex effects like semiflexibility and substitution.

Findings

Exact solutions for systems without cyclization and with loops

Numerical solutions for homopolymerization of flexible polymers

Validation with Monte-Carlo simulations

Abstract

We develop a simple recursive approach to treat reversible condensation polymerization with cyclization. Based upon a minimum set of balance equations, the law of mass action, Gaussian chain statistics, and the assumption of independent reactions, we derive exact analytical solutions for systems without cyclization, for systems containing only smallest loops, or systems that exclusively form loops. Exact numerical solutions are computed for the general case of a homopolymerization of flexible precursor polymers. All solutions were tested with Monte-Carlo simulations. A generalization for good solvent is discussed and it is shown that this generalization agrees with preceding work in the limit of low and high polymer volume fractions. The new aspect of our approach is its flexibility that allows for a rather simple generalization to more complex situations. These include different kinds of reversible linear polymerization, non-linear polymerization, first shell substitution effect, semiflexibility, or a low molecular weight cut-off for cyclization.