Department of Environmental and Energy Chemistry, Faculty of Engineering, Kogakuin University, Tokyo, Japan.
J Colloid Interface Sci. 2011 Nov 15;363(2):707-10. doi: 10.1016/j.jcis.2011.08.014. Epub 2011 Aug 11.
Fresh or hydrolyzed sodium alginate was used as a material for preparing calcium alginate microspheres, and a drastic difference in porous structure was observed between them, even though the other materials and the preparation method except for the sodium alginate were exactly the same. When fresh sodium alginate was used, nonporous microspheres were obtained. In contrast, when 82-day-hydrolyzed sodium alginate, whose molecular weight became 7% of the molecular weight of the fresh sodium alginate, was used, porous microspheres with 6.5 times larger BET surface area were obtained. XPS studies indicated that the atomic ratio of Ca, the crosslinker of the alginic acid polymer, was almost the same in both cases. Therefore, the difference in porous structure was not attributed to the amount of crosslinking points, but to the low-molecular-weight compounds formed by hydrolysis, and they would work as pore-generating agents.
新鲜或水解的海藻酸钠被用作制备海藻酸钙微球的材料，尽管其他材料和制备方法除了海藻酸钠完全相同，但它们的多孔结构却有很大的不同。当使用新鲜的海藻酸钠时，得到的是无孔微球。相比之下，当使用分子量降低到新鲜海藻酸钠的 7%的 82 天水解海藻酸钠时，得到的是具有 6.5 倍更大 BET 表面积的多孔微球。XPS 研究表明，两种情况下的交联剂 Ca 的原子比几乎相同。因此，多孔结构的差异不是归因于交联点的数量，而是归因于水解形成的低分子量化合物，它们起到了生成孔的作用。
