Design of Better Particle Coatings with Respect to Attrition Resistance

Many coated particles show wear due to transport after production. In this research we have focused on assessing this wear, in particular attrition and have related this attrition resistance to the particle coating properties. By measuring the coating properties on the particle, as casted films but also as spray coated films a clear correlation is found between resistance to attrition and the visco-elastic properties of the coating. This finding will make the optimization easier when attrition wear needs to be reduced, since polymer will not have to be tested randomly, which is often the case, but it can be done much more direct by looking into the visco-elastic properties of the coating. Several HPMC and PVA coatings were tested and the most of the results will be presented. The research opens a new field of assessing coating properties without applying them on to coated particles, which can reduce the time of product development a lot.