Linking roller compaction and tableting: Simple extensions of Kawakita and Ryshkewitch-Duckworth

Roller compaction (RC) is widely used in pharmaceutical manufacturing but produces ribbons with non-uniform porosity, complicating the prediction of tablet properties. Here, we present a reduced-order framework that links roller compaction and tableting by minimally extending established constitutive models to predict tablet porosity and tensile strength with low additional data demand. Peak RC stress was calculated using the Johanson model as a function of specific compaction force, while ribbon porosity was estimated with the Kawakita relation, which we extended to capture pre-compaction effects, enabling estimation of the final tablet porosity. Tablet tensile strength was described by the Ryshkewitch–Duckworth relation, extended by a pressure-like term representing granule hardening during pre-compaction. A global sensitivity analysis was performed, and the framework was validated against literature data for microcrystalline cellulose (MCC) and mannitol, including response-surface evaluation over RC and tableting conditions. Fitting the empirical parameters yielded excellent agreement for tablet porosity (MCC: R 2 = 0.99; mannitol: R 2 = 0.96) and tensile strength when using experimental porosity (MCC: R 2 = 0.98; mannitol: R 2 = 0.99). Predicting tensile strength via model-predicted porosity remained strong. Sensitivity analysis identified tableting pressure and Kawakita model parameters as the dominant factors influencing final porosity and tensile strength. The two simple model extensions integrate RC and tableting into a unified, easy-to-apply framework suitable for parameter exploration and model-based design of experiments. Despite known simplifications, the framework consistently captured trends for both plastic and brittle excipients. • Unified model links roller compaction and tableting • Prediction of tablet porosity and strength • Reduced-order linkage of roller compaction and tableting using two lumped interface parameters