Novel monomers from sugars: synthesis, catalysis, polymerisation and applications in degradable electronics

糖类新型单体：合成、催化、聚合及其在可降解电子产品中的应用

• 批准号: 2282305
• 金额: --
• 依托单位: University of Bath
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2019
• 资助国家: 英国
• 起止时间: 2019 至 无数据
• 项目状态: 已结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2282305
• 关键词: Novel; monomers; sugars; synthesis; catalysis

The topic of research for this PhD will be the synthesis of novel degradable polymers sourced from sugars and their applications in energy applications, namely battery technology. Currently, mainstream lithium-ion batteries (LIBs) as well as new generation batteries rely on aqueous electrolytes to transport cations between the electrodes. These types of batteries pose serious safety concerns for a number of reasons. On the other hand, solid polymer electrolytes (SPEs) are a promising class of alternative electrolyte materials which can offer high mechanical strength, flexibility and a lower cost than other solid electrolytes such as ceramics.Polyethylene oxide (PEO) has been heavily studied as a SPE material and the model for the ionic conductivity of PEO is well understood. However, whilst PEO is a good conductor of lithium ions, it does have some limitations that means it will not be a suitable material in any realistic future battery applications. In order to develop future SPE-based batteries, novel materials are needed which can improve upon the properties of polymers such as PEO.Polycarbonates have been shown to be a promising class of polymers for SPE materials with the potential for high ionic conductivity. They can also be sourced from natural feedstocks and have the advantage of biodegradability for their end of life. However, polycarbonates can be difficult to functionalise and therefore difficult to tune for desired properties.The Buchard group already has a platform of sustainable polycarbonates made from the reaction of CO2 with renewable diols from sugars. These polymers also have alkene functionalisation in the carbon backbone with the potential ideal for developing novel biodegradable SPE materials from renewable feedstocks. This research will look to assess the lithium-ion conducting capabilities of these polymers with varying degrees of crystallinity, molecular weight, cis/trans ratios of the alkene, etc. The alkene bond will also be functionalised (post-polymerisation) to incorporate lithium-coordinating groups and/or any other functional groups which will provide the polymer with properties ideal for SPEs. Moreover, the replacement of oxygen with sulfur in the carbonate moiety, giving monothiocarbonate and xanthate monomers, will also be explored as a way to access better polymer properties for SPE materials.Following the successful synthesis of novel polymers, rigorous mechanical and physicochemical characterisation will be performed, for which multinuclear NMR, mass spectrometry (MALDI), Size-Exclusion Chromatography (SEC), Differential Scanning Calorimetry (DSC), X-ray scattering and stress/strain tests will be important techniques. Electrochemical characterisation of the polymers with lithium salts will then be investigated, in collaboration with Prof F. Marken (second supervisor at Bath), via ionic conductivity and cyclic voltammetry measurements. Promising materials will be put forward in the construction of real coin cell devices in collaboration with Prof D. Mercerreyes (Basque Center for Macromolecular Design and Engineering, Spain). The application of our new polymers as SPE materials will be tested in LIBs but also in other promising battery types, such as Li-S and Na-ion batteries. Other energy applications will also be considered, such as the functionalisation of the alkene bond with conducting organic motifs for the synthesis of novel polymers for uses in organic photovoltaic devices. This work will have the potential for collaboration with Dr H. Bronstein in Cambridge.

该博士的研究主题将是合成来源于糖的新型可降解聚合物及其在能源应用中的应用，即电池技术。目前，主流锂离子电池（LIB）以及新一代电池都依赖于水性电解质在电极之间传输阳离子。这些类型的电池由于多种原因而引起严重的安全问题。另一方面，固体聚合物电解质（SPE）是一类很有前途的替代电解质材料，它具有高的机械强度、柔韧性和比陶瓷等固体电解质更低的成本，聚氧化乙烯（PEO）作为SPE材料已经得到了大量的研究，PEO的离子电导率模型也得到了很好的理解。然而，虽然PEO是锂离子的良导体，但它确实有一些限制，这意味着它在任何现实的未来电池应用中都不是合适的材料。为了开发未来的SPE基电池，需要能够改善聚合物如PEO的性能的新型材料。聚碳酸酯已被证明是一类有前途的SPE材料，具有高离子电导率的潜力。它们也可以来源于天然原料，并具有在其寿命结束时可生物降解的优点。然而，聚碳酸酯很难进行功能化，因此很难调整所需的性能。Buchard集团已经拥有一个可持续聚碳酸酯平台，该平台通过二氧化碳与来自糖的可再生二醇反应制成。这些聚合物在碳骨架中也具有烯烃官能化，具有从可再生原料开发新型生物可降解SPE材料的潜在理想。这项研究将着眼于评估这些聚合物的锂离子传导能力与不同程度的结晶度，分子量，顺式/反式比的烯烃等烯烃键也将功能化（后聚合）纳入锂配位基团和/或任何其他官能团，这将提供聚合物的性能理想的SPE。此外，还将探索用硫取代碳酸酯部分中的氧，得到单硫代碳酸酯和黄原酸酯单体，作为获得SPE材料的更好聚合物性能的一种方法。在成功合成新型聚合物之后，将进行严格的机械和物理化学表征，为此，将使用多核NMR，质谱（MALDI），尺寸排阻色谱（SEC），差示扫描量热法（DSC），X射线散射和应力/应变测试将是重要的技术。然后将与F。马尔肯（巴斯第二主管），通过离子电导率和循环伏安法测量。有前途的材料将提出在建设真实的硬币电池设备的合作与D。Mercerreyes（巴斯克高分子设计和工程中心，西班牙）。我们的新型聚合物作为SPE材料的应用将在LIB以及其他有前景的电池类型中进行测试，例如Li-S和Na离子电池。其他能源应用也将被考虑，如官能化的烯烃键与导电有机基序的新型聚合物的合成用于有机光伏器件。这项工作将有可能与H博士合作。剑桥的布朗斯坦。