功能化碳硼烷类燃速催化剂的设计、合成及性能研究

A good solid propellant should have a stable burning rate and a low pressure exponent. For this purpose, one of the best ways is to add a burning-rate catalyst into the propellant. In the process of chemical modification of the burning-rate catalyst, the most important and fundamental requirements are to improve the chemical stability and simultaneously minimize the migration. In this project, with the aim of enhancing the efficiency of burning-rate catalyst, an idea on the design of new functional carborane-based burning-rate catalyst, which the high heating value and massive bulk of carborane is utilized to preclude effectively the migration, is proposed. And the functional burning-rate catalyst will be prepared through introducing ferrocenes on the carborane cage structure via coupling reaction or cyclization reaction. By changing the thermal decomposition reaction condition, the kinetics and mechanism of the burning-rate catalyst, as well as the influence of the molecular structure or molecular size of the functional burning-rate catalyst on the thermal decomposition performance will also be clarified. With the aid of relevant thermochemical analysis methods such as Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC), the following work related to the burning-rate catalyst will be carried out in detail, i. e. , the catalytic effect on the thermal decomposition of oxidant and fuel respectively, and the structure-activity relationship (SAR) of catalytic thermal domcomposition. The achievement of the project will enrich academic accumulations on the SAR of functional burning-rate catalyst, and provide theoretical basis for the development of highly effective burning-rate catalyst.

添加燃速催化剂是改善固体推进剂燃烧性能行之有效的方法之一。通过分子结构优化与分子尺寸调节，提高燃速催化剂的化学稳定性和抗迁移性是燃速催化剂改性研究需要解决的重要基础科学问题。本项目拟以碳硼烷分子作为母体结构，设计、合成一系列新型的功能化碳硼烷类燃速催化剂；研究其热分解动力学行为，提出可能的反应机理，总结分子结构对自身热分解性能的影响规律；研究碳硼烷类燃速催化剂分别对氧化剂、燃料热分解的催化作用，关联催化剂分子结构与氧化剂、燃料热分解性能的关系。本项目将在功能化燃速催化剂的构效关系研究方面取得一定的学术积累，并为高效燃速催化剂的研制提供理论依据。

碳硼烷是一类性能优异的功能材料，广泛应用于催化剂、材料、超分子及医药化学等领域。针对单烷基取代碳硼烷的精准合成方法，开发了一种高效合成单取代碳硼烷的铜催化格氏偶联反应路线。反应通过三环己基膦配体对铜盐金属中心配位，实现了一系列烷基及芳基格氏试剂作为偶联试剂的高效官能化，并具有显著提高的反应收率。该反应同样适用于其他卤烷基碳硼烷分子的修饰，有望在功能化硼簇化合物的合成中得到广泛的应用。针对1-溴甲基碳硼烷的中心碳原子空间位阻大、反应活性低的问题，建立了镍催化大位阻化合物1-溴甲基碳硼烷参与的偶联反应。针对十硼烷毒性大、笼状碳-氢键难以活化的科学问题，发展了一种钯催化碳硼烷锂盐化合物与（杂环）芳基卤代物的偶联反应，通过C（笼状）-C（sp2）键的选择性构建实现了芳基取代碳硼烷的合成。不同结构的芳基碘代物、芳基溴代物以及杂环芳基卤化物均可以顺利参与反应，并具有良好的官能团兼容性。该反应为功能性碳硼烷的合成提供了新方法，并有望用于医药和配位化学领域的研究中。