海藻纳米纤丝化纤维素气凝胶及其碳化研究

Cellulose is one of the most abundant renewable resources on earth. Globally， more than 150 Trillion tons of cellulose is generated per year。 Cellulose products can meet the human requirements for environment protection and biocompatibility of the new materials. Nanofibrillated cellulose (NFC) aerogels which are assembled from NFC possess the self-contained excellent properties such as biocompatibility and biodegradability besides the merits of traditional aerogels. As a developing biopolymer material, NFC aerogels have great potential applications in the fields of medicine and biology. In this project,we plan to prepare NFC aerogel by using freeze drying technique from seaweed NFCs which are collected from laminaria, gelidium, and enteromorpha, respectively. And the obtained seaweed NFC aerogels will be converted to carbon aerogels under high-temperature carbonization treatment. We will investigate the formation and structure of H-bond network between the solvent and functional groups on the surface of NFC，which is built at different temperatures. And we need to determine how to obtain the NFC aerogel with controllable tunnel and network by using freeze drying technique. Similarly，the polycondensation and dehydrogenation reactions in the NFC aerogel carbonization process will be studied to find the parameters which can affect the performance of the carbon aerogels. This project will provide theoretical support for the development of the abundant seaweed cellulose resource.

维素是地球上最丰富的可再生资源之一, 全球每年植物纤维素的产量超过1500亿吨。纤维素制品能满足人们对新材料的环保性和生物相容性的需求。尤其是由纳米纤丝化纤维素组装成的气凝胶材料，在具备传统气凝胶特性的同时融入了自身的优异性能，如良好的生物相容性和可降解性，是一个不断发展的生物类聚合物材料，在医药和生物领域具有良好的应用前景。本课题基于冷冻干燥技术，以海带、石花菜和浒苔等海藻中提取的纳米纤丝化纤维素（NFC）制备成多孔的气凝胶材料，并将之高温碳化成炭气凝胶。探讨NFC表面官能团如何与分散液形成氢键网络，在不同温度下搭建塑造网络结构，并如何通过冷冻干燥实现孔道结构和网络结构可控的纤维素气凝胶；在制备炭气凝胶的过程中，探讨纤维素热解时发生的缩聚和脱氢反应对最终炭气凝胶性能的影响。为开发丰富的海洋藻类纤维素资源提供理论支持。

海藻是地球上最丰富的可再生资源之一。对海藻生物质的碳化研究，尤其是由海藻及其提取物组成的多级孔、纤维、气凝胶等材料，此类材料在具备传统复合材料特性的同时融入了自身优异的凝胶、络合等性能，从而实现基于海藻生物质的多种微/纳结构的可控合成。本课题以海带、石花菜和浒苔等海藻中提取物制备浒苔多级孔材料、微/纳米海藻纤维、卡拉胶气凝胶材料，并将之高温碳化成生物质碳及其复合材料。探讨海藻酸钠表面官能团如何与分散液形成氢键网络及其阻燃性能的提高，在不同温度下搭建塑造网络结构，并如何通过冷冻干燥实现孔道结构和网络结构可控的生物质材料；在制备生物质碳及其复合材料的过程中，探讨海藻提取物热解时发生的缩聚和脱氢反应对最终复合材料性能的影响。探索海藻及其提取物在能源存储与转化领域的应用研究，为开发丰富的海洋藻类资源提供理论支持，同时满足人们对新材料的可控合成的需求。