To overcome the limitations of conventional cook-off models in full-chain prediction of explosive formulations and charge behaviors while eliminating post-ignition temperature field singularities， a multi-component parameter fitting model was systematically applied to investigate the thermal decomposition response and cook-off characteristics of polymer-bonded explosives （PBX-9501， PBX-9502， and novel PBX-4）. A component parameter-driven full-process simulation framework was established through coupled multi-physics modeling integrating Arrhenius reaction kinetics with the JWL product gas equation of state， enabling numerical characterization from initial thermal decomposition to final casing rupture. Validation results demonstrated that ignition time prediction errors for PBX-9501 and PBX-9502 were 3.4% and 5.7% respectively compared with experimental data. Ignition time deviation for PBX-4 prediction reached 2.3% against validation experiments. Dynamic regulation of product gas parameters stabilized explosion temperatures within 3328-3502 K， effectively resolving temperature singularity issues inherent in traditional solid-phase cook-off models.