Experimental and theoretical evaluation of micron sized polymer particles as a means to control gloss and surface roughness of coatings

 
In this work a theoretical model is assessed which relates gloss to the characteristic surface parameters Rq and L. Rq is the root mean square roughness and L is the autocorrelation length of that roughness. Four types of matting particles were examined for their ability to lower gloss. Very good agreement is found between the theoretical model and the experimental data. It is also found that spherical polymer particles can be effective in reducing gloss of coatings. These spherical polymer particles have a much narrower particle size distribution, thus in principal allowing for finer control over the gloss reduction at multiple angles, particularly the ratio of 85° to 60° gloss..