Designing Moisture and Light Stable Group 14 Homo- and Alternating Polymers including Polystannanes

在过去的4年里，我们在瑞尔森的研究集中在制备适合聚合的超高配位(5配位)锡烷单体。在温和的金属催化下，锡二氢化合物上的柔性和非柔性-C，O-和-C，N-配体发生脱氢反应，得到了分子量适中的高配位聚锡烷。这些独特的聚合物在溶液和固体状态下都表现出显著的光稳定性改善(聚二丁基锡烷的90d比10min)。这种超配位聚合物还表现出更好的耐湿性(在常温下7天，而聚(二丁基)锡烷为1小时)，由于空间密集的锡中心的几何形状，锡-锡键的访问受到阻碍。在我们的研究中，我们还发现了一种通过二烷基和二芳基锡二氢化物与二烷基和二芳基锡二氢化物在室温下缩合来制备交替聚锡烷的方法。这种缩合聚合路线为根据需要在每个锡原子或每个其他锡原子上制备具有定制功能的独特设计的聚锡烷提供了可能性。我们对锡化学的进步所做的贡献导致了更多光和水分稳定的聚锡烷，使从这些本征导电材料实现可印刷电子产品的最终目标变得更加现实。我们建议在以下具体领域继续目前的这些努力： 1)优化光和水稳定的高分子量膜形成聚锡烷：这项工作将寻求确定和制备能够提高总体稳定性的配体，特别是5配位聚锡烷中的水分稳定性。交替的疏水和吸光取代基将为聚锡烷提供基本的光和湿度稳定性的组合。 2)推拉式锡烷：使用精选的锡二胺和锡二氢化物的缩合化学来获得一系列本征的半导体推拉式聚锡烷。这些聚锡烷材料的结构必须在喷墨打印头配方方面确保聚合物的易溶解性、稳定性和加工性，并保留固有的推拉式聚合物线材的优势。这将是理想的探索循环伏安法(以显示稳定性)以及电导率测量技术，以支持这些特性。 3)第14族交替聚合物：这涉及二氢化物或二胺锡烷与二氢化物和二胺硅烷、日耳石和铅烷之间的缩合。要确定促进这类杂化聚合物的条件，需要仔细匹配各种化学成分。目前还不知道具体的交替第14族聚合物。这种化学打开了对这些以前未知的材料的访问。

Our research efforts at Ryerson over the last 4 years have focussed on the preparation of hypercoordinated (5-coordinate) stannane monomers suitable for polymerization. Mild metal-catalysed dehydrogenation of both flexible and non-flexible -C,O- and -C,N- ligands attached to tin dihydrides has led to the isolation of modest molecular weight, hypercoordinated polystannanes. These unique polymers demonstrate a significant improvement in light stability (> 90 d vs 10 min for poly(dibutyl)stannane) in both the solution and the solid state. The hypercoordinate polymers also display improved resistance to moisture (7 d at ambient vs 1 hr for poly(dibutyl)stannane), with access to tin-tin bonds hindered by the geometry of the sterically crowded tin centres. In our investigations, we have also discovered an accessible route to the preparation of alternating polystannanes via the room-temperature condensation of dialkyl and diaryl tin diamides with dialkyl and diaryl tin dihydrides. This condensation polymerization route has opened the possibilities to the preparation of uniquely designed polystannanes with customized functionality on every tin atom, or every other tin, as required. Our contribution to the advances in tin chemistry leading to more light and moisture stable polystannanes has made the end goal of achieving printable electronics from these intrinsic conducting materials a closer reality. We propose a continuation of these current efforts in the following specific areas: 1) Optimized Light and Moisture Stable High molecular weight film forming Polystannanes: This effort would seek to identify and prepare ligands which enhance overall stability, in particular moisture stability in 5-coordinate polystannanes. Alternating hydrophobic and light absorbing substituents would provide the essential combination of light and moisture stability for polystannanes. 2) Push-Pull Stannanes: Employ condensation chemistry of select tin diamides and tin dihydrides to access a series of intrinsic semi-conducting push-pull polystannanes. The construction of these polystannane materials must ensure facile polymer solubility, stability, and processability in terms of formulation for an inkjet printhead and retain the advantages of an intrinsic push-pull polymer wire. This will be ideally probed by cyclic voltammetry (to show stability) as well as conductivity measurement techniques to support these characteristics. 3) Alternating Group 14 polymers: This involves the condensation between dihydride or diamide stannanes and dihydride and diamide silanes, germanes and plumbanes. A careful match of chemistries is required to identify conditions that promote hybrid polymers of this type. No specific alternating Group 14 polymers are now known. This chemistry opens access to these previously unknown materials.