Transition-Metal Coordination in Polymer Blends

几种形成配位配合物的含金属聚合物共混物是本研究的重点。模型化合物是低分子量的盐，其二价金属中心从d-嵌段第一行的铁到铜，以及第二行的钌到银。配体是聚（4-乙烯基吡啶）或含有4-乙烯基吡啶重复单元的共聚物。热分析通过差示扫描量热法和偏振光学显微镜将被用来生成这些二元混合物的热力学相图。在分子水平上，高分辨率碳-13固态核磁共振和傅里叶变换红外光谱将用于探测影响混合的微环境因素。天然丰度氮-15固态核磁共振实验在超大转子将提供一个直接探测金属配体sigma键，涉及氮上的孤对。提出的通过金属离子带来的配位型相互作用增强混相是重要的，因为大多数聚合物混合物不能混相，这限制了它们的用途。任何改进都会产生新的结构材料。

Several metal-containing polymer blends which form coordination complexes are the focus of this investigation. The model compounds are low-molecular-weight salts in which the divalent metal centers range from iron to copper in the first row of the d-block, and ruthenium to silver in the second row. The ligand is poly(4- vinylpyridine) or copolymers that contain 4-vinylpyridine repeat units. Thermal analysis via differential scanning calorimetry and polarized optical microscopy will be employed to generate thermodynamic phase diagrams of these binary mixtures. At the molecular level, high-resolution carbon-13 solid-state nuclear magnetic resonance and Fourier transform infrared spectroscopies will be used to probe microenvironmental factors that influence mixing. Natural abundance nitrogen-15 solid-state nuclear magnetic resonance experiments in oversized rotors will provide a direct probe of metal-ligand sigma-bonding that involves the lone pair on nitrogen. The proposed enhancement of miscibility via coordination-type interactions brought about by metal ions is important because most polymer mixtures are not miscible, which limits their usefulness. Any improvement would lead to new structural materials.