Conduction and Mechanical Properties of Single-Ion Conducting Ionomers

单离子导电离聚物的导电和机械性能

• 批准号: 1404586
• 负责人: Ralph Colby
• 金额: $ 57.2万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-08-01 至 2019-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1404586&HistoricalAwards=false
• 关键词: Conduction; Mechanical; Properties; Single; Ion

TECHNICAL SUMMARY: Ionomers based on polar monomers are an important class of energy materials for applications that require single-ion conduction. In this research, three novel types of materials are being made: (1) High molecular weight Reversible Addition-Fragmentation chain Transfer (RAFT) ionomers that are random copolymers of an anionic monomer and a polar solvating monomer, (2) RAFT diblock copolymers with one ionomeric random copolymer conducting block and one structural block and (3) polar low-Tg (glass transition temperature) non-volatile plasticizers. By fully understanding the dielectric and viscoelastic response of the RAFT copolymer ionomers, the optimal compositions for conduction of Li counterions will be identified and then RAFT diblock copolymers will be prepared with identical composition of the soft block. In this way, the effects of confinement to lamellar or cylinder phases can be identified, using also X-ray scattering to detail morphology. The linear viscoelastic response of these polymers will be understood using simple extensions of Rouse and reptation models to include the effects of ion association lifetimes. Polar low-Tg non-volatile plasticizers will be added to those materials to boost ion conductivity and dielectric constant of the soft domains, while lowering Tg. Thus far, siloxane oligomers with polar solvating side chains seem best, owing to their very low T (between -80 C and -60 C). By exploring the parameter space of ion content, polarity and specific solvation ability of both the comonomer and the plasticizer, the goal is to guide future materials design in the energy materials arena. For the diblock copolymers the modulus near room temperature is also crucial and the effects of these parameter variations on modulus will be measured to understand the tradeoff between ion conduction and mechanical properties, and their link to morphology and the amount of plasticizer in each microphase.NON-TECHNICAL SUMMARY: Applications that will be enabled by new materials in the energy arena simultaneously require high conductivity of one (and only one) type of ion and good mechanical strength. This research on ion conduction and mechanical properties of polymeric energy materials aims to understand the structure-property relations in polymers that conduct only one type of ion, such as lithium for advanced batteries. One strong advantage of developing materials for lithium ion transport that only conduct lithium (single-ion conductors as opposed to the lithium salts used in batteries today that also must conduct a negatively charged ion) is that both battery charging and access to the power of the battery could be as much as 100 times faster. If successful, the fundamental knowledge generated from this research will result in the understanding needed to design polymeric materials for a variety of specific energy applications, including advanced batteries, fuel cells, solar cells, ionic actuators, supercapacitors and energy harvesting devices; each of which require ion transport and mechanical strength. These applications offer societal benefits that may improve the lives of humans across the globe. Additionally, the project will involve education and training of graduate and undergraduate students.

技术综述：基于极性单体的离聚体是一类重要的能量材料，适用于需要单离子导电的应用。在本研究中，合成了三种新型材料：(1)高分子量可逆加成-断裂链转移(RAFT)离聚体，它们是阴离子单体和极性溶剂化单体的无规共聚物；(2)具有一个离子无规共聚物导电嵌段和一个结构嵌段的RAFT二嵌段共聚物；(3)极性低玻璃化转变温度(Tg)的非挥发性增塑剂。通过充分了解RAFT共聚物离聚体的介电和粘弹性响应，将确定导电Li反离子的最佳组成，从而制备出具有相同软嵌段组成的RAFT两嵌段共聚物。通过这种方式，还可以使用X射线散射来详细描述形貌，从而识别限制对层状或圆柱状相的影响。这些聚合物的线性粘弹性响应将使用Rouse和Reptation模型的简单扩展来理解，以包括离子缔合寿命的影响。将在这些材料中添加极性低Tg非挥发性增塑剂，以提高软磁区的离子导电性和介电常数，同时降低Tg。到目前为止，具有极性溶剂化侧链的硅氧烷齐聚物似乎是最好的，因为它们的T很低(在-80℃到-60℃之间)。通过探索共聚单体和增塑剂的离子含量、极性和比溶剂化能力的参数空间，目的是指导未来能源材料领域的材料设计。对于两嵌段共聚物，室温附近的模数也是至关重要的，将测量这些参数变化对模数的影响，以了解离子导电性和力学性能之间的权衡，以及它们与每个微相中的形态和增塑剂用量的关系。非技术摘要：新材料在能源领域的应用同时要求一种(且只有一种)离子的高导电性和良好的机械强度。这项关于聚合物能量材料的离子传导和力学性能的研究旨在了解只传导一种离子的聚合物中的结构-性能关系，例如用于先进电池的锂。开发只传导锂离子的锂离子传输材料的一个强大优势是，电池充电和获取电池电力的速度都可以快100倍。如果成功，这项研究产生的基础知识将导致对为各种特定能源应用设计聚合物材料所需的理解，包括先进电池、燃料电池、太阳能电池、离子致动器、超级电容器和能量收集设备；每一种都需要离子传输和机械强度。这些应用提供了社会效益，可能会改善全球人类的生活。此外，该项目还将涉及研究生和本科生的教育和培训。