Design of Copolymers Based on Sequence Distribution for a Targeted Molecular Weight and Conversion

Abstract

It is challenging to track explicit copolymer sequences and related measures using continuum kinetic models. We developed a generalized framework based on kinetic Monte Carlo (KMC) to model free radical polymerization of any number of monomers to obtain the explicit sequence and its distribution. The KMC framework was applied to copolymerization of butyl acrylate/methyl methacrylate (BA/MMA) and methyl acrylate/methyl methacrylate (MA/MMA), and the simulation output was compared with experimental results. Sequence characteristics that were not accessible via experiments were then predicted. Explicit monomer sequence information was used to construct operating diagrams to design a representative copolymer recipe with a specific sequence target as a function of molecular weight and monomer conversion.

Acceleration of kinetic monte carlo simulations of free radical copolymerization: A hybrid approach with scaling

“…The kinetic parameters for this system are available in the literature, [36][37][38][39][40] and previous studies have shown that it is sufficient to use constant apparent propagation and termination rate coefficients in this system. 15,41 This is taken into account in this model by assigning a large value to the monomer diffusion coefficient, so that the chemistry-controlled contribution to the rate coefficients always dominates over the diffusioncontrolled contribution. Physical properties and kinetic parameters are listed in Table 3.…”

“…One area where there has been growing interest in KMC is polymerization . The attractiveness of KMC is mainly because of two reasons.…”

“…2,3 One area where there has been growing interest in KMC is polymerization. [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21] The attractiveness of KMC is mainly because of two reasons. First, many polymeric reactions, especially termination and propagation, can be diffusion controlled, dependent on the reaction conditions.…”

“…13 As a final example, Regatte et al developed a KMC model to predict synthesis recipes to achieve sequence and molecular weight targets of copolymers synthesized via conventional free radical polymerization. 15 Because of the details tracked within KMC methods, execution is more costly computationally than deterministic modeling. 26 KMC methods usually model only an extremely small control volume that represents a well-mixed reaction system.…”

Chain‐by‐Chain Monte Carlo Simulation: A Novel Hybrid Method for Modeling Polymerization. Part I. Linear Controlled Radical Polymerization Systems

“…[10,11] At the other extreme, Monte Carlo type probabilistic methods, more specifically kinetic Monte Carlo (kMC) developed by Gillespie, [12] attempt to obtain a solution for the entire distribution by simulating the behavior of a finite ensemble selected to approximate the actual physical system. [13][14][15] For example, the polymerization medium might be approximated by a collection of initiator molecules, and a collection of monomer molecules. Each species can undergo a specific set of chemical reactions at a probability proportional to the rate of each reaction.…”