壳聚糖/三聚氰胺-甲醛气凝胶的制备与表征

Preparation and Characterization of Chitosan/Melamine-formaldehyde Aerogel

采用三聚氰胺(M),壳聚糖(CS)和甲醛(F)水溶液缩合制备一种低体积收缩率,高韧性的新型混合气凝胶。MF/CS质量比是本研究的关键参数,因为它对胶凝时间,体积收缩和结构性质有重要影响。由于引入了柔性CS聚合物主链,所有壳聚糖/三聚氰胺-甲醛(CMF)气凝胶的体积收缩率(<5%)低于纯MF气凝胶(28.7%)的体积收缩率。SEM和BET结果表明,混合气凝胶属于介孔材料,具有典型的三维多孔结构。DMA结果发现CMF气凝胶具有高抗压强度和良好的可变形绝缘性,适用作承载材料。

A new hybrid aerogel with low volume shrinkage and high toughness prepared by aqueous condensation of melamine（M）, chitosan（CS） and formaldehyde（F）. The MF/CS mass ratio was the key parameter in this study as it had the major effects on gelation time, the volume shrinkage and structural properties. Due to the introduce of the flexible CS polymeric backbone, the volume shrinkage of all the CMF aerogels（ 5%） was considerably lower than that of the pure MF aerogel（28.7%）. The results of SEM and BET indicated that the hybrid aerogels belonged to the mesoporous material, which showed a typical three-dimensional porous structure. The results of DMA that indicated the CMF aerogels, which had high compression strength and great deformability insulation, would be suitable to perform as load-bearing materials.