While reaction engineering of low-molecular weight compounds mainly focuses on equilibria and selectivities, polymer properties are tremendously influenced by molecular weight distribution as well as branching structure. In order to determine the branching structure of low-density polyethylene (LDPE) copolymers in dependence on chosen process conditions, a Monte-Carlo approach was developed. By modeling the topology as well as the comonomer distribution in the polymer chains a deeper insight in the process-microstructure-properties relationship is gained.