Zhao Wenting, Yan Xiaoxing
Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China.
College of Furnishings and Industrial Design, Nanjing Forestry University, Nanjing 210037, China.
Polymers (Basel). 2022 Mar 29;14(7):1393. doi: 10.3390/polym14071393.
Thermochromic microcapsules were prepared with a thermochromic compound as core material and urea formaldehyde as wall material. The molar ratio of urea and formaldehyde, the mass ratio of core material to wall material, the concentration of emulsifier, and rotating speed were selected to make a four-level and three-factor L(3) orthogonal test. It was found that the molar ratio of urea and formaldehyde had the greatest influence on the coating rate of microcapsules. The effects of molar ratio of urea and formaldehyde on the discoloration temperature and coating rate of microcapsules were studied. When the molar ratio of urea to formaldehyde was 1:1.6, the core material: wall material ratio was 4:7, the concentration of emulsifier was 5.0%, and the rotating speed was 1600 rpm, the performance of the microcapsules was the best. When the microcapsule content was 20.0%, the color difference of the paint film was the largest, the gloss and hardness of the paint film decreased with increasing microcapsule content, and the impact resistance of the paint film first increased and then decreased with increasing microcapsule content. The adhesion of the paint film remained unchanged, and was grade 1. When the microcapsule content was 20.0%, the performance of the paint film was at its best. This provides a basis for the application of thermochromic coatings.
以热致变色化合物为芯材、脲醛为壁材制备了热致变色微胶囊。选取尿素与甲醛的摩尔比、芯材与壁材的质量比、乳化剂浓度和转速进行四水平三因素L(3⁴)正交试验。结果发现，尿素与甲醛的摩尔比对微胶囊的包覆率影响最大。研究了尿素与甲醛的摩尔比对微胶囊变色温度和包覆率的影响。当尿素与甲醛的摩尔比为1:1.6、芯材:壁材比为4:7、乳化剂浓度为5.0%、转速为1600 rpm时，微胶囊的性能最佳。当微胶囊含量为20.0%时，漆膜的色差最大，漆膜的光泽度和硬度随微胶囊含量的增加而降低，漆膜的耐冲击性随微胶囊含量的增加先增大后减小。漆膜的附着力保持不变，为1级。当微胶囊含量为20.0%时，漆膜的性能最佳。这为热致变色涂料的应用提供了依据。
