Characterization of fillers used in abrasive articles by means of inverse gas chromatography and principal component analysis

Abrasive articles consists of cutting particle—very often from electrocorundum, filler—inorganic compound, e.g. potassium fluoroborate or cryolite, binder—novolak resin and wetting agent—resol. The most important stages during manufacturing of grinding tools are: the coverage of the abrasive by wetting agent and proper hardening. The fillers play a very important role during the work of the grinding tools—they collect the heat and prevent the melting of resin. The surface properties of the components of grinding tools influence the interactions between them and the properties of the final product.Surface properties of different kinds of the fillers were examined by means of inverse gas chromatography (IGC). Dispersive component of the surface free energy γSD at relative humidities: 30%, 60% and 90% and at various temperatures: 278, 283, 288 and 293 K was determined. It provided the data on stability of the fillers during their storage and/or weathering. The influence of the type of the filler on the hardening process by differential scanning calorimetry (DSC) was also studied.Principal component analysis (PCA) was applied to search the influence of the temperature and humidity onto the γSD values for various fillers. This analysis showed that changes of the surface properties of fillers are significant at higher humidity close to 90%. Furthermore, PCA demonstrated that the type of filler does not influence meaningfully the hardening process.This approach has shown usefulness of IGC and calorimetric methods in studying the properties of abrasive articles as well as PCA in the interpretation of physicochemical characteristics of abrasive materials.