Synthesis of surface-grafted conjugated polyelectrolyte multilayers as well as conjugated polymer hydrogels and a systematic study of interdependence of mixed conduction and degree of swelling

有机混合离子-电子导体（OMIEC）是有机电化学晶体管（OECTs）中的活性材料。这些材料在偏压下在溶胀状态下应显示出高的离子和电子电荷传输。混合导电完全取决于在偏压下在水介质中的溶胀程度，因此，需要控制OMIEC的溶胀程度以研究和理解不同性质的相互作用，例如电子传输、离子传输、溶胀和水介质中的稳定性。我们计划合成具有溶胀性控制以及高混合离子的新型OMIEC，电子传导性能，在OECT器件中具有操作稳定性的高效系统，而不需要外部交联剂。我们的假设是，通过使用a）共辄多层膜和B）共辄聚合物水凝胶，OMIEC的溶胀程度的期望的调节和控制是可行的。两种系统都将进行表面接枝，以确保膜在电解质中的耐久性。通过LbL组装依次沉积阴离子和阳离子共轭聚电解质，可以实现共轭聚电解质多层膜。共轭聚合物水凝胶将通过使用可聚合的重氮丙二酸酯（MAz）的共轭聚电解质的C-H插入交联（CHic）来制备。这两种概念都提供了独特的组织般的软机械性能与有机半导体的电子性能相结合。主要目的是控制溶胀度，以阐明溶胀对OMIECs在两种类型的系统中的电子和离子性质的影响。在前者中，溶胀度将通过双层的数量来调节，而在后者中，溶胀度将通过交联度来控制。调节共轭双折射多层膜溶胀的另一个参数是通过改变电解质的盐浓度和离子强度。我们特别关注： 1.多层膜的LbL组装在溶胀程度、控制、响应时间、循环和OECT薄膜稳定性方面与CHic方法有何不同？2.混合导电如何取决于膨胀程度？阐明了混合导电作为溶胀的函数，如本建议中所设想的，有利于理解复杂的相互作用的溶胀和混合离子的电子传输特性的第一次在一个系统的方式。这一建议提供了一个基本步骤，建立指导方针，在设计有效的OMIECs，满足所有所需的先决条件，最佳的溶胀，高离子和电子传输以及在水介质中的稳定性。

Organic mixed ion-electron conductors (OMIEC)act as active materials in organic electrochemical transistors (OECTs). These materials should show high ionic and electronic charge transport in swollen state under bias. The mixed conduction fully depends on the degree of swelling in aqueous media under bias and therefore, a control over the degree of swelling of the OMIEC is required to study and understand the interplay of diverse properties such as electronic transport, ionic transport, swelling and stability in aqueous media.In this project, we plan the synthesis of novel OMIECs with a control of swellability as well as high mixed ion-electron conduction properties towards highly efficient systems with operational stability in OECT devices without the requirement of external cross-linkers. Our hypothesis is that, a desired tuning and control of the degree of swelling of OMIECs is feasible by the use of a) conjugated polyelectrolyte multilayers and b) conjugated polymer hydrogels. Both systems will be surface grafted to ensure durability of the films in electrolyte. The conjugated polyelectrolyte multilayers will be realized by sequentially depositing anionic and cationic conjugated polyelectrolytes via LbL assembly. The conjugated polymer hydrogels will be prepared by C-H insertion cross-linking (CHic) of conjugated polyelectrolytes using polymerizable diazomalonic ester (MAz). Both concepts offer unique tissue-like soft mechanical properties combined with the electronic properties of organic semiconductors. The main aim is to control the degree of swelling to elucidate the influence of swelling on electronic and ionic properties of OMIECs in both types of systems. In the former, the degree of swelling will be tuned by the number of double layers, whereas in the latter it will be controlled by the degree of cross-linking. Another parameter to tune the swelling of the conjugated polyelectrolyte multilayers is by varying the salt concentration and ionic strength of the electrolyte. We specifically focus on: 1. How does the LbL assembly of multilayers vary from CHic approach in terms of degree of swelling, its control, on response time, cycling and thin film stability of an OECT? 2. How does mixed conduction depend on the degree of swelling ?The elucidation of mixed conduction as a function of swelling as envisaged in this proposal, facilitates the understanding of complex interplay of swelling and mixed-ionic electronic transport properties for the first time in a systematic way. This proposal offers a fundamental step towards establishing guidelines in designing efficient OMIECs which fulfil all the desired prerequisites of optimum swelling, high ion and electron transport as well as stability in aqueous medium.