LAMMPS Chemical Crosslinking of Polymer

Hi,

I am new to LAMMPS, and this mailing list along with the online documentation has been super helpful in getting me started with the simulations. I was searching through the examples and archived mailing lists regarding how to set up chemically bonded (crosslinked) polymers. I came across this post: https://lammps.sandia.gov/threads/msg34585.html discussing how to build polymer melts. However, there’s a caveat in the solution that the polymer has to follow a step growth polymerization process. Is there a method or example that shows how to do a free radical polymerization process in LAMMPS from input LAMMPS template monomer files?

Thank you!

  • Kasey

Hi Kasey,

It sounds like you want to model polymer systems at an atomistic or coarse grained scale. With the details of these simulations it is not possible to model a free-radical polymerization process because there is not an explicit definition of electrons. If you are interested in polymer properties, there are numerous ways to construct polymer chains for simulation which can be used to predict these properties, but these are going to be model systems that are independent of the experimental synthesis procedure (although they may relate to the product of synthesis). If you are interested in the synthesis procedure you can either perform ab initio calculations or attempt to develop a computational “pseudo-synthesis” approach that can connect with experimental methods (this is very time consuming and generally requires lots of data and collaboration).

If you would like to narrow what exactly you would like to study (polymer chemistry, composition, property, and at what conditions) I am happy to make recommendations for LAMMPS functionalities and pre/post processing software to help you with your problem.

It is always nice to see someone reading the archives!

Best,
Dylan