• talc;
  • dry coating;
  • wettability;
  • work of adhesion;
  • dispersion


Even though dispersion operations have been the object of several investigations, the importance of the different parameters and especially the physicochemical and surface properties are rarely treated. Dry particle coating can be used to create new generation materials. In such processes, host particles are mechanically coated with guest particles, without using solvents and subsequent drying, to create new functionalities or to improve initial characteristics. This study examines the surface properties of talc particles modified by dry coating with hydrophobic silica particles. Two parameters have been studied: the concentration of silica particles and the dry coating processing time. Both parameters allow modifications of the work of adhesion of talc particles with water, which is a characteristic of wettability. This change of wettability can consequently influence the dispersion rate of talc in water. © 2010 American Institute of Chemical Engineers AIChE J, 2011