Amine-Borane Dehydropolymerisation for the Synthesis and Exploitation of Polyaminoboranes as Routes to New BN-Containing Materials

聚氨基硼烷，-（H2 BNHR）n-，是具有主链B-N骨架的聚合物，其与聚烯烃，-（H2 CNO 3）n-密切相关。然而，它们的基本材料和化学性质基本上是未开发的，尽管作为高性能硼基陶瓷和六方氮化硼的可加工前体的潜在应用。这是因为缺乏具有挑战性的高效且稳健的有机金属催化剂体系的组合，从而使聚合物具有可控的分子量和分散性。然而，Weller实验室最近的研究结果表明，在理解和利用有机金属催化剂设计和机理方面取得了重大进展，并且受控的胺-硼烷脱氢聚合“有序”现在是可能的。这个博士学位的雄心勃勃的目标是开发强大的，可扩展的定制聚氨基硼烷的路线，允许更广泛的材料开发。新的第9族（Co，Rh，Ir）过渡金属催化剂系统将通过机制主导的设计策略合成和探索令人兴奋的新“BN”聚合物材料的聚合物合成。通过以控制聚合物链长和分散性以及使用的成本和实用性的期望度量为目标，将开发在更大规模上操作的催化剂系统。将这些向前推进到材料发现中，将探索允许使用这些聚合物作为新材料的分子前体的用户友好的方法。低温处理将产生各种令人兴奋的新“BN”材料，其中聚合物特性（使用开发的催化剂）将有助于定义所产生的技术重要材料的材料特性，特别是3D BN材料：六方氮化硼和硼碳氮化物具有非常有趣的光学，电子，热和化学特性。将有一个创新周期，材料化学领域有前途的领先者将导致新的和已知的催化剂系统的改进。该项目是安德鲁韦勒（约克，催化）和理查德杜思韦特博士（约克，无机材料合成和表征）之间的合作小组。博士生将成为广泛技术的专家，这将使他们能够开发新的有机金属催化剂系统（合成），详细的动力学和机理研究，然后将这些用于材料合成和表征。特别是技能将发展：有机金属合成，催化机制的阐明，NMR光谱，X射线晶体学和材料合成和表征技术。在博士学位结束时，候选人将在广泛的基础和更实用的有机金属/无机材料化学技术方面拥有广泛而深入的专业知识。

Polyaminoboranes, -(H2BNHR)n-, are polymers with main-chain B-N backbones that are closely related to polyolefins, -(H2CCHR)n-. However, their fundamental materials and chemical properties are essentially unexplored, despite potential applications as processable precursors to high-performance boron-based ceramics and hex-boron nitride. This is because the challenging combination of efficient and robust organometallic catalyst systems that give polymer of controllable molecular weight and dispersity is missing. However, recent results from the Weller lab have demonstrated a significant advance in understanding and harnessing both organometallic catalyst design and mechanism, and the controlled amine-borane dehydropolymerisation "to order" is now a possibility. The ambitious objectives of this PhD are to develop robust, scalable, routes to bespoke polyaminoboranes, that allows for their wider materials exploitation. New group 9 (Co, Rh, Ir) transition metal catalyst systems will be synthesised and explored for polymer synthesis of exciting new "BN" polymeric materials, through a mechanism-led design strategy. By targeting the desirable metrics of control of polymer chain length and dispersity and cost and practicality of use, catalyst systems that operate on larger scale will be developed. Taking these forward into materials discovery, user friendly methods that allow for the use of these polymers as molecular precursors to new materials will be explored. Low temperature processing will lead to a variety of exciting new "BN" materials where the polymer characteristics (using the catalysts developed) will help define the materials properties of the resulting technologically important materials, especially 3D BN materials: hexagonal boron nitride and boron carbon nitride have very interesting optical, electronic, thermal and chemical properties. There will be a cycle of innovation, with promising leads in materials chemistry leading to the refinement of new and known catalyst systems. The project is collaborative between the groups of Andrew Weller (York, catalysis) and Dr Richard Douthwaite (York, inorganic materials synthesis and characterisation). The PhD student will become expert in a wide range of techniques, that will allow them to develop new organometallic catalyst systems (synthesis), detailed kinetics and mechanism studies, and then take these through to materials synthesis and characterisation. In particular skills will be developed in: organometallic synthesis, elucidation of mechanism in catalysis, NMR spectroscopy, x-ray crystallography and materials synthesis and characterisation techniques. At the end of the PhD the candidate will have broad and deep expertise in a wide range of fundamental, and more applied, organometallic/inorganic materials chemistry techniques.