A mechanistic powder compaction equation: Accounting for the effects of particle properties

A mechanistic powder compaction equation is proposed to incorporate physical particle properties into the prediction of tablet tensile strength based on the bonding strength and bonding number. This investigation aims to establish insights between the interplay of particle and material properties including primary particle size, Sauter mean diameter, surface energy, Young's modulus, and Poisson's ratio to calculate the bonding strength and bonding number with tablet porosity and compaction pressure. There are two fitting parameters, brittle parameter k and corrected contact number c are related to powder ductility tendency and contact area after compression, respectively. The predicted tablet tensile strength is driven by two terms: bonding number and bonding strength. The model is tested with three sizes of microcrystalline cellulose by characterizing compacted tablets for a range of compaction pressures. The main novelty of this framework is that it can provide a mechanistic insight into the interplay of physical particle properties to predict tablet strength. Ultimately, this model aims to provide guidelines for excipient selection and tablet formulation development.