Void Space Structure of Compressible Polymer Spheres and Consolidated Calcium Carbonate Paper-Coating Formulations

A methodology is presented for the study of the void space structure of consolidated calcium carbonate paper-coating formulations and compressible polymer spheres, using mercury porosimetry. Two limitations of mercury porosimetry are addressed:  first, that the shrinkage of compressible samples causes an apparent increase in void volume, and, second, that large void spaces shielded by smaller ones are not intruded until anomalously high applied pressures of mercury are reached. The first limitation is overcome by means of a new correction procedure which, uniquely, also allows the measurement of the bulk modulus of the continuous solid phase of a porous sample. Shielding effects are taken into account by means of our software package known as Pore-Cor, which generates a three-dimensional structure which has both a mercury intrusion curve and porosity in close agreement with experiment. The simulated permeabilities provide realistic and useful values, which cannot be measured experimentally.