A thermochemical and rheological model incorporating inhibition time for highly reactive polyester resins in liquid moulding processes

This work presents the development of a comprehensive model to describe the cure kinetics and viscosity behaviour of polyester-based resin systems used in liquid composite moulding applications. The model accounts for both inhibition and diffusion effects, providing a unified equation that simplifies the complex integral expressions often required in sequential or piecewise approaches. Thermogravimetric analysis (TGA), Differential Scanning Calorimetry (DSC), and rheological characterization were performed to assess the thermal stability, curing behaviour, and viscosity changes over a range of isothermal temperatures. Time-temperature graphs generated by the model highlight critical regions for processing, including the processability window and the rapid crosslinking region. These insights are crucial for optimizing process parameters in the large-scale manufacturing of composite parts, particularly for complex geometries. • A novel cure kinetics model that accounts for inhibition and diffusion effects. • A viscosity model coupled with the cure kinetics model and inhibition effects. • Processability maps show the available injection time vs. process temperature. • Simulation compares HPRTM of polyester with inhibitor vs. highly reactive resin.