氨基酸全生物基苯并噁嗪的合成及其在CO2吸附中的应用

Benzoxazines as a new type of high performance thermal setting resin are developed on the basis of traditional phenolic resins, which could be synthesized by Mannich condensation from phenolic derivate, primary amine and formaldehyde (paraformaldehyde or formaldehyde aqueous solution) with flexible molecular design. But their synthetic raw materials are still mainly dependent on fine petroleum and chemical products, which are also beset by the lack of oil resources. Recently, extensive researches have been widely carried out to obtain fully bio-based ploybenzoxazines from bio-based materials instead of fine petrochemical raw materials. Compared with the very rich phenols in nature, the bio-based amine compounds are less. As renewable raw materials, amino acids are source widely and cheap. In this work, natural and unnatural amino acids are firstly selected as the amine sources to synthesize a series of novel fully bio-based benzoxazine resins, whose properties would be comparative with traditional petroleum-based benzoxazine resin or even better. It will be able to realize the exploitation and utilization as well as environmental protection of the rich bio-based materials. Based on this basis, the amino acids with rich nitrogen atoms (e.g. Histidine and Arginine) are selected as the amine source to synthesize a series of fully bio-based benzoxazine resins, which are further used as carbon sources to prepare porous carbon materials. It is expected to open up a new approach to the application of fully bio-based polybenzoxazine to achieve a strong adsorption of carbon dioxide.

苯并噁嗪是在传统酚醛树脂的基础上发展起来的一类新型高性能热固性树脂，该分子通常可以由一种酚类物质、伯胺类物质和甲醛（多聚甲醛或者甲醛水溶液）通过Mannich缩合反应得到，具有灵活的分子设计性。但其合成原料仍然主要依赖精细石油化工产品，同样受到石油资源匮乏的困扰。以生物基原料替代精细石油化工原料合成全生物基苯并噁嗪树脂是近年来生物基材料领域的研究热点之一，受到广泛关注。和自然界中非常丰富的酚类物质相比，生物基胺类化合物则为数较少。氨基酸来源广泛、价格低廉，本项目的主要设计思想是将天然和非天然氨基酸作为胺源，合成全生物基苯并噁嗪，其性能和传统苯并噁嗪性能相当甚或更优，实现资源丰富的生物基材料的开发利用和环境保护。在此基础上，选择富含氮原子的氨基酸（如组氨酸、精氨酸）作为胺源，合成全生物基苯并噁嗪，并将其作为碳源，制备含氮多孔碳材料，以期实现对二氧化碳的强吸附，开辟全生物基苯并噁嗪应用的新途径

传统的苯并噁嗪树脂材料多以石油化工产品作为原材料，在当今石油资源匮乏的年代，不再符合“绿色、环保、可持续”的发展理念。选用来源于自然界的可持续性原料制备生物基苯并噁嗪成为了苯并噁嗪发展的一大重要方向。. 项目以氨基酸为胺源原料，根据不同酚源以及胺源的特点制备了一系列生物基苯并噁嗪热固性树脂，填补了生物基苯并噁嗪胺源不足的空白。多孔炭材料因其耐酸碱耐高温、化学稳定高等特点被广泛用于CO2吸附领域。结合天然氨基酸中的N，O，S等杂原子特性以及生物基聚苯并噁嗪的热性能，以氨基酸聚苯并噁嗪为制备多孔炭材料的前驱体，根据氨基酸小分子中杂原子的高含量以及苯并噁嗪交联后的高残炭率等性能，通过炭化和活化工艺，制备了一系列具有优良CO2气体吸附性能和良好电化学性能的杂原子掺杂多孔炭材料。所得到的炭材料中，TMF3比表面积最大，达到了2283 m2g-1，其在273K温度下的CO2吸附量可达7.05 mmol/g。研究了杂原子掺杂炭材料的CO2吸附模型与吸附热力学性能，并表征了炭材料对模拟烟道气的吸附性能，研究了其中CO2气体的穿透性能，结果表明所制备的炭材料（XCF5g）在模拟烟道气的穿透过程中对N2与CO2气体的吸附具有选择性，且分离系数可达到8.23。将制备得到的杂原子掺杂炭材料应用在了超级电容器的电极材料中，VCF5g炭材料的在0.1 Ag-1的电流密度下的比电容可达到310 Fg-1，表明这类生物基苯并噁嗪未来在超级电容器用的新型炭电极材料中具有良好的应用前景。. 首次同时以氨基酸作为酚源和胺源，制备出了全氨基酸基苯并噁嗪材料，将环酪氨酸二肽引入生物基苯并噁嗪树脂材料的制备中。相比于传统的双酚A-苯胺型苯并噁嗪树脂材料，环酪氨酸二肽型氨基酸基苯并噁嗪树脂的热稳定性更加优异，800 ℃下的残碳率高达43%。此外，以柔性链段聚醚胺作为胺源，与环酪氨酸二肽反应制备出一系列同时具备高拉伸强度和高拉伸倍数的苯并噁嗪自修复膜；该自修复膜对大肠杆菌及金黄色葡萄球菌也表现出良好的抗菌活性。