High-temperature polymerization has recently become of interest for industry because it yields higher reaction rates, and thus less reaction time, lower viscosity, and higher conversions. However, it also leads to new challenges for process engineering in regards to materials, reactor design, and, most of all, process modeling. Because practically all kinetic research in the field of polymerizations has been realized for rather low temperature ranges (mostly below the glass transition temperature), the correct modeling of a high-temperature polymerization requires the investigation of various parameters, such as thermal initiation effects, depropagation reactions, etc., and a careful adaptation of existing models for kinetics at significantly higher temperatures. The attention is focused on the modeling of the gel effect based on existing models available from the literature. Therefore, two different types of models, one semiempirical and one based on the free-volume theory, are examined for their applicability to high-temperature polymerization by comparison with the experimental results from differential scanning calorimetry batch polymerizations. Model fitting was realized using the software package PREDICI by CiT GmbH, Rastede, Germany.