Raptopoulos Grigorios, Choinopoulos Ioannis, Kontoes-Georgoudakis Filippos, Paraskevopoulou Patrina
Inorganic Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece.
Industrial Chemistry Laboratory, Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis Zografou, 15771 Athens, Greece.
Polymers (Basel). 2022 Mar 21;14(6):1254. doi: 10.3390/polym14061254.
Τhis work describes the synthesis of PLA-grafted M-alginate (g-M-alginate; M: Ca, Co, Ni, Cu) aerogels. -lactide (LA) was attached on the surface of preformed M-alginate beads and was polymerized, using stannous octoate as catalyst and the -OH groups of the alginate backbone as initiators/points of attachment. The material properties of g-M-alginate aerogels were not affected much by grafting, because the linear PLA chains grew on the M-alginate framework like a brush and did not bridge their points of attachment as in polyurea-crosslinked M-alginate aerogels. Thus, all g-M-alginate aerogels retained the fibrous morphology of their parent M-alginate aerogels, and they were lightweight (bulk densities up to 0.24 g cm), macroporous/mesoporous materials with high porosities (up to 96% /). The BET surface areas were in the range of 154-542 m g, depending on the metal, the nature of the alginate framework and the PLA content. The latter was found at about 15% / for Ca- and Ni-based materials and at about 29% / for Co- and Cu-based materials. Overall, we have demonstrated a new methodology for the functionalization of alginate aerogels that opens the way to the synthesis of polylactide-crosslinked alginate aerogels with the use of multifunctional monomers.
这项工作描述了聚乳酸接枝的M-海藻酸盐（g-M-海藻酸盐；M：钙、钴、镍、铜）气凝胶的合成。丙交酯（LA）附着在预制的M-海藻酸盐珠粒表面，并使用辛酸亚锡作为催化剂，以海藻酸盐主链的-OH基团作为引发剂/附着点进行聚合。接枝对g-M-海藻酸盐气凝胶的材料性能影响不大，因为线性聚乳酸链像刷子一样在M-海藻酸盐骨架上生长，不像聚脲交联的M-海藻酸盐气凝胶那样桥接其附着点。因此，所有g-M-海藻酸盐气凝胶都保留了其母体M-海藻酸盐气凝胶的纤维形态，它们是轻质的（堆积密度高达0.24 g/cm³）、具有高孔隙率（高达96%）的大孔/中孔材料。根据金属、海藻酸盐骨架的性质和聚乳酸含量，BET表面积在154 - 542 m²/g范围内。对于钙基和镍基材料，后者约为15%/，对于钴基和铜基材料，约为29%/。总体而言，我们展示了一种海藻酸盐气凝胶功能化的新方法，为使用多功能单体合成聚丙交酯交联的海藻酸盐气凝胶开辟了道路。
