Tao Yu, 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 24;14(7):1304. doi: 10.3390/polym14071304.
In this paper, self-healing microcapsules were prepared by using melamine-formaldehyde (MF) resin as the wall material and shellac as the core material repairing agent. In order to explore the effect of the four factors (i.e., the HLB value of emulsifier, the type of solvent, the mass ratio of shellac to rosin, and the rate of rotating) on the comprehensive performance of microcapsules, and orthogonal experiments with four factors and three levels were carried out. The results showed that the hydrophilic lipophilic balance (HLB) value of the emulsifier was the most important influencing factor. In order to further explore the relationship between the HLB value of the emulsifier and the morphology of the microcapsules and the coating rate as well as to further optimize the performance of the microcapsules, taking the HLB value of the emulsifier as the single factor variable, single-factor tests were carried out. The results showed that when the HLB value was 12.56, the microcapsules of melamine-formaldehyde resin-coated shellac-rosin mixture had a uniform distribution and high coating rate. In order to explore the self-healing properties of waterborne coatings with microcapsules, the microcapsules prepared by single-factor experiments were mixed into the waterborne coatings at mass ratios of 0%, 3.0%, 6.0%, 9.0%, 12.0%, and 15.0%. It showed that the elongation at break of the waterborne coating with the addition of 3.0% microcapsule at mass fraction was improved, and it had a higher repair rate. This study provides a new research idea for the optimization and characterization of the self-healing properties of waterborne coatings.
本文以三聚氰胺 - 甲醛（MF）树脂为壁材、紫胶为芯材修复剂制备了自修复微胶囊。为探究乳化剂的亲水亲油平衡（HLB）值、溶剂类型、紫胶与松香的质量比以及转速这四个因素对微胶囊综合性能的影响，进行了四因素三水平的正交试验。结果表明，乳化剂的亲水亲油平衡（HLB）值是最重要的影响因素。为进一步探究乳化剂的HLB值与微胶囊形态、包覆率之间的关系以及进一步优化微胶囊性能，以乳化剂的HLB值为单因素变量进行了单因素试验。结果表明，当HLB值为12.56时，三聚氰胺 - 甲醛树脂包覆紫胶 - 松香混合物的微胶囊分布均匀且包覆率高。为探究含微胶囊水性涂料的自修复性能，将单因素实验制备的微胶囊按质量比0%、3.0%、6.0%、9.0%、12.0%和15.0%混入水性涂料中。结果表明，质量分数添加3.0%微胶囊的水性涂料的断裂伸长率得到提高，且具有较高的修复率。本研究为水性涂料自修复性能的优化与表征提供了新的研究思路。
