Use of tablet tensile strength adjusted for surface area and mean interparticulate distance to evaluate dominating bonding mechanisms

In this study, tablet tensile strength has been adjusted for tablet surface area and the average distance between particles in compacts of different m aterials. The aim of the study was to evaluate the feasibility of using thi s concept to assess the dominating interparticulate bonding mechanisms. Adj ustment of the tensile strength for both tablet surface area and mean pore radius gave similar bonding strength values for materials bonding mainly by weak distance forces (crystalline lactose, sucrose, and microcrystalline c ellulose) almost independently of compaction pressure. However, particle si ze and other factors may still affect the compensated strength values. The bond strength was much higher and more varied for materials bonding also wi th solid bridges (potassium chloride, sodium chloride, and possibly also so dium bicarbonate and amorphous lactose). For these materials, particle size and compaction pressure had a substantial effect on the bond strength, it is probably the formation of continuous bridges between adjacent particles that is important in these materials rather than the surface properties and the average distance between particles positioned at some distance from ea ch other. Hence, adjusting the tensile strength of compacts does not necess arily reflect all the dominating factors responsible for interparticulate b onding. Nonetheless, adjustment for tablet surface area and mean pore radiu s allowed discrimination between different dominating interparticulate bond ing mechanisms in these compacted materials.