Compression shear strength and tableting behavior of microcrystalline cellulose agglomerates modulated by a solution binder (polyethylene glycol).

Abstract

To investigate the possibility of modulating the compression shear strength of agglomerates by the incorporation of a solution binder and to study the subsequent effect on the deformation behavior and tablet forming ability of the agglomerates. Various concentrations (0.5 to 10%) of polyethylene glycol were incorporated as a solution binder into microcrystalline cellulose agglomerates of different porosity (10 and 20%) and the shear strength of the agglomerates, as evaluated by the 1/b value of the Kawakita equation, and the permeability to air and tensile strength of tablets formed from them were determined. Increased agglomerate porosity and concentration of polyethylene glycol reduced the 1/b values, which led to the formation of tablets with a lower permeability. A decreased tablet permeability corresponded to an increased tablet tensile strength except that the highest binder content was associated with a drop in the tablet tensile strength. The solution binder reduced the agglomerate shear strength, which was expressed as an increased degree of agglomerate deformation during compression. The latter seemed to be controlled by both agglomerate porosity and shear strength. The main role of the solution binder in improving the agglomerate compactability was to increase the degree of deformation of agglomerates during compression.