  This work introduces a method for generating generalized structures of
amorphous polymers using simulated polymerization and molecular dynamics
equilibration, with a particular focus on amorphous polymers. The techniques
and algorithms used in this method are described in the main text, and example
input scripts are provided for the GMXPolymer code, which is based on the
GROMACS molecular dynamics package. To demonstrate the efficacy of our method,
we apply it to different glassy polymers exhibiting varying degrees of
functionality, polarity, and rigidity. The reliability of the method is
validated by comparing simulation results to experimental data for various
structural and thermal properties, all of which show excellent agreement.
