An orthogonal experiment with four factors and three levels was designed. Nine different microcapsules were prepared by changing four factors: the core-wall ratio, emulsifier concentration, reaction temperature, and rotation speed. Through an analysis of the microcapsule yield and morphology, it was determined that the microcapsule of sample 6 performed the best in the orthogonal test and that the core-wall ratio was the largest factor affecting the microcapsule morphology and yield. In order to further optimize the performance of the microcapsules, single factor independent tests were carried out using the core-wall ratio as a single variable. It was found that the microcapsules with the core-wall ratio of 0.75:1 had good micro morphology and yield. The properties of the coating were the best when the microcapsules were added into the primer and the topcoat at the same time with an additional amount of 10.0%. The mechanical properties of the coating containing cellulose microcapsules and the coating without cellulose microcapsules were tested. Cellulose can enhance the toughness of the microcapsules, inhibit the generation of microcracks, and enhance the performance of the coating to a certain extent. The elongation at break of the coating with cellulose microcapsules was 9.49% higher than that without cellulose and was 11.1% higher than that without cellulose microcapsules.
Keywords: cellulose; microcapsules; wood paint coating.