海藻酸钠/POSS有机-无机杂化中空微囊的制备与性能

Preparation of Sodium Alginate/POSS Organic-Inorganic Hybrid Hollow Microcapsules and Their Properties

以一种水溶性的阳离子型多面体低聚倍半硅氧烷(POSS)代替传统的氯化钙凝固浴,通过滴制法与海藻酸钠(SA)制备了SA/POSS有机-无机杂化微囊,并对其结构与性能进行了表征。FT-IR、XRD、SEM、TG及溶胀实验结果表明:POSS和SA之间存在较强的静电作用力,POSS的引入降低了SA分子排列的有序性,SA/POSS有机-无机杂化微囊为非晶态结构。微囊的外壁最为致密,从外到内结构逐渐变得疏松直至内部中空;微囊的热稳定性优于海藻酸钠。SA/POSS中空微囊在去离子水和HCl溶液中很快达到溶胀平衡,平衡溶胀比分别为17.2%~33.1%和15.9%~20.3%;而在PBS缓冲液中会破碎直至溶解。

Awater-soluble cationic polyhedral oligomeric silsesquioxane (POSS) instead of the traditional calcium chloride coagulation bath was employed together with sodium alginate (SA) to prepare a series of hybrid organic and inorganic microcapsules (SA/POSS) via dropping method. The structure and properties of the obtained SA/POSS microcapsules were also characterized. It could be found from the results of FT-IR, XRD, SEM, TG and swelling experiment that a strong electrostatic interaction exist between POSS and SA. The introduction of POSS wea-kened the ordered arrangement of SA molecules, and SA/POSS organic-inorganic hybrid microcapsules presented amorphous structure. Speci-fically, the microcapsules possessed a compact outer wall and a hollow interior, with the structure gradually become looser from outside to inside. In addition, SA/POSS microcapsules show superior thermal stability to SA. The SA/POSS hollow microcapsules could reach swelling equilibrium in deionized water and HCl solution quickly, with the equilibrium swelling ratios of 17.2%-33.1% and 15.9%-20.3%, respectively, while they would break in PBS buffer and finally dissolved.