丙烯酸共聚物囊壁的正十八烷微胶囊的制备和性能表征

以二丙烯酸1,4-丁二醇酯为交联剂, 成功制备了甲基丙烯酸甲酯-甲基丙烯酸共聚物为壁材, 正十八烷为囊芯的相变材料微胶囊. 采用扫描电子显微镜(SEM)、差示扫描量热仪(DSC)和热重分析仪(TG)分别考察了单体与芯材投料比、单体浓度和交联剂的含量对微胶囊形貌、相变热性能、热稳定性能的影响. 实验结果表明: 随着单体与芯材投料比或单体浓度的增加, 微胶囊表面均变得致密, 壁厚增加; 随着交联剂含量的增加, 微胶囊的表面变得更加致密光滑, 热稳定性显著增强; 随着单体与芯材投料比的增大, 微胶囊热焓值减小, 被包裹的囊芯含量减少.

Fabrication and Characterization of Microencapsulated n-Octadecane with an Acrylic Co-polymeric Shell

Microcapsules containing n-octadecane were synthesized using a methyl methacrylate/methacrylic acid co-polymeric shell with 1,4-butylene glycol diacrylate (BDDA) as a cross-linking agent. The surface morphologies,thermal physical properties, and thermal stabilities of the microencapsulated n-octadecane(MC_(18)) were investigated by scanning electronic microscopy, differential scanning calorimetry, and thermogravimetric analysis, respectively.Experimental results showed that by increasing the mass ratio of monomer/core or the monomer concentration, the surfaces become more compact and the shell thickness increase. The thermal stability of MC_(18) can be improved by adding a cross-linking agent and the surface becomes much more compact and smoother by increasing the feed of the cross-linking agent BDDA. The thermal resistance temperature of MC_(18) improves obviously. As the mass ratio of monomer/core increases, the enthalpy of MC_(18) decreases and the encapsulation rate is lower.