The Use of Simulation Techniques in Developing Kinetic Models for Polymerization

Abstract

The demands on simulations of polymerization reactions grow continuously, as do their capabilities. Using two examples it will be demonstrated how the use of detailed kinetic models in such simulations can contribute to the development of experimental strategies for determining rate coefficients, assist in mechanistic analysis and enable feasibility studies about operational strategies. Using the high-temperature butyl acrylate polymerization as an example, it will be illustrated, based on detailed analytical information, how the kinetic scheme of the butyl acrylate polymerization expands to a complex network of elementary reactions. Based on this model an experimental strategy will be developed for the selective determination of the individual rate coefficients. A comparison of the results from these simulations with experimental data shows that a realization of the developed concept appears to be within reach. The second example is based on a kinetic scheme of the, high-temperature high-pressure, polymerization of ethene. In addition, using this kinetic scheme, the capability of nitroxyl species in establishing a controlled radical polymerization mechanism in polymerizations that show high polymerization rates and significant quantities of intraand inter-molecular branching reactions will be tested. This feasibility study will examine the potential effect a nitroxyl species has on the kinetic mechanism with respect to its stability and the structural characteristics of a polymer that results from such a polymerization.

Estimating Kinetic Parameters for the Spontaneous Polymerization of Glycidol at Elevated Temperatures

“…The underlying process is modeled mathematically and kinetic parameters are calculated by comparison of experimental data to simulations. How simulation studies can improve existing polymerization processes was discussed before by Ray16 and Busch et al17…”

Monte Carlo simulations of rigid biopolymer growth processes

“…35 In addition, the application of this approach might suggest an explanation of the mechanism by which motor proteins modulate biopolymer dynamics, as they are known to alter the exchange of tubulin subunits at growing ends. Such improvements could include allowing for hydrolysis effects and nonequal load distribution factors for the protofilaments.…”

Anionic Ring-Opening Polymerization Simulations for Hyperbranched Polyglycerols with Defined Molecular Weights

“…The set of reaction equations can easily be transformed into ordinary, previously discussed differential equations (ODEs). 30,39,40 The ODEs, which are often referred to as population balance equations (PBE), 41 can be used to solve an initial value problem (IVP) using numerical methods to simulate time trajectories of the concentrations of every molecular species in the system. 42 The described system is especially challenging because it incorporates a two-dimensional polymer species which could only be simulated in very simple cases.…”

“…The time-dependent changes in the molecular species can now be simulated using eqs – for the kinetic reaction rate coefficients k ion,1 , k thr,1 , k ion,2 , k thr,2 , and k t . The set of reaction equations can easily be transformed into ordinary, previously discussed differential equations (ODEs). ,, …”