Simulating Styrene polymerization using Cayenne.

[edwardiwuchukwu]

Good day, I am working on comparing the deterministic and stochastic trajectories of the polymerization of styrene in free radical reaction. I find it challenging to use the module. How do I obtain a plot of :( a. )The polydispersity index(PDI) versus time
(b.)Molecular weight(Mw) versus time(c.)average molecular number(Mn) versus time.Attached is a schematics representation of the reaction. I look forward to valuable contributions.
Thank you.

The above schematic was gotten from an annual journal and here is the citation :
Curteanu, Silvia. “Modeling and Simulation of Free Radical Polymerization of Styrene under Semibatch Reactor Conditions.” Open Chemistry, vol. 1, no. 1, 2003, pp. 69–90., doi:10.2478/bf02479259.

[sriki18]

Hello, thank you for reaching out. I am not sure how PDI and molecular weight are defined for your problem. What I can tell you is that you can access the simulation results by doing:

# Get all the results
results = sim.results
# Get results only for one or more species
y = results.get_species(["A", "C"])

And you should be able to access what is in the y object to get the values vs. time, which will help you compute the PDI and molecular weight. Does this answer your question @teddiclax

[edwardiwuchukwu]

Hello Srikiran,
Thank you for the response. I do not clearly understand the instructions, can you help produce the pseudocode or the code ? I am new to Cayenne and currently studying the module.

Also, my understanding of the concept is based on simulating the set of ordinary differential equations produced from the kinetics of the polymerization reaction then, the relationship between the PDI,Mw ,Mn and X versus time could be simulated. But, the task is to produce the Stochastic Simulation.

Can you check the equations (B.1 to B.9 andB.10 to B.12) on page 26 of this reference article:
Gamba, Ignacio L., et al. “Residence Time Distribution Determination of a Continuous Stirred Tank Reactor Using Computational Fluid Dynamics and Its Application on the Mathematical Modeling of Styrene Polymerization.” International Journal of Chemical Reactor Engineering, vol. 10, no. 1, 2012, https://doi.org/10.1515/1542-6580.3057.