A study on the coherence of compacted binary composites of microcrystalline cellulose and paracetamol

This paper describes and interprets the coherence and the tensile strength of bi-component compacted tablets, composing a mixture of a poorly compactable drug, paracetamol and a very cohesive and ductile carrier, microcrystalline cellulose (MCC), Avicel (R) PH 102, using the concepts of the stored elastic strain in conjunction with the particle size and the relative volume fraction of the powders. Cylindrical compacts of the bi-component tablets, at various compositions formed at a common ultimate stress of 99 MPa, were subsequently fractured using the indirect tensile test method (Brazilian test method) to obtain a measure of their tensile strength. Various inter-relations between the compaction and tensile rupture characteristics are described. A simple model, which may predict the required volume fraction of MCC to produce a cohesively viable tablet is suggested, and applied to the current system. The results show to some extent the consistency of the suggested model with the experimental results. (c) 2005 Elsevier B.V. All rights reserved.