Simultaneous milling and coating of inorganic particulates with polymeric coating materials using a fluid energy mill

A fluid energy-based method and apparatus was used to simultaneously mill and coat coarse particles with the presence of various coating materials, including: three micron-sized particles-carnauba wax, polyethylene (PE), and polytetrafluoroethylene (PTFE) particles, and one type of nanoparticle, PTFE. The coating performance of polymeric materials and their effect on the breakage of the coarse particles were studied. The Young's modulus of the coating materials and the materials' size ratio were found to be critical in controlling the coating quality. The polymeric coating, working as a lubricant and cushion layer, absorbs part of the high kinetic energy and results in the larger particle size of fluid energy mill-ground product. Experimental and simulation results suggest that side-sweep attrition plays a role in breakage of core particles.