以亲水性的二氧化硅(SiO2)纳米粒子稳定的水包油Pickering乳液为模板,利用聚氧化丙烯二醇和二苯基甲烷二异氰酸酯预聚物(PPG-TDI)与二乙烯三胺(DETA)在油水界面的聚合反应制备了聚脲(PU)包裹苯乙酸乙酯(EPA)-异佛尔酮二异氰酸酯(IPDI)有机/无机杂化微胶囊。通过控制不同油水比得到不同粒径大小的微胶囊,粒径分布为20~90μm。热重分析表明EPA-IPDI的装载量达到53 wt%。扫描电子显微镜图片可以看出,微胶囊表面光滑,呈规整球形,厚度均一,约2μm。
The Pickering oil-in-water emulsion stabilized by silicon dioxide( SiO2) nanoparticles was used as a template to fabricate novel microcapsules. The shell of this microcapsule was polyurea( PU),which was achieved by the oil-water interfacial polymerization between polypropylene glycol-toluene diisocyanate( PPGTDI) and diethylenetriamine( DETA). Ethyl phenylacetate( EPA)-isophorone diisocyanate( IPDI) was successfully encapsulated into the microcapsule. It was found the size and distribution of composite microcapsules could be tailored by altering the volume ratio of water and oil. Optical microscope images exhibited that the diameters of composite microcapsules were in a range of 20 to 90 μm. From thermal gravimetric analysis( TGA),the encapsulation mass of EPA-IPDI was estimated to be 53 wt%. Scanning electron microscopy( SEM) observation indicated that the capsules had a smooth surface and a uniform thickness of ca. 2 μm.