项目名称: 基于空间位阻及多重非共价键作用的高稳定性螺旋聚乙炔的合成及结构调控
项目编号: No.21204021
项目类型: 青年科学基金项目
立项/批准年度: 2013
项目学科: 高分子科学
项目作者: 黄炜
作者单位: 华东师范大学
项目金额: 25万元
中文摘要: 聚乙炔的螺旋结构在较高温度或极性溶剂中常常变得非常不稳定,这大大限制了螺旋聚乙炔的应用范围。在本课题中,我们通过多步反应将大体积的平面芳香基团、多酰胺基团以及手性中心引入到乙炔分子中,聚合后制备得到了一系列基于空间位阻及多重非共价键作用的高稳定性螺旋聚乙炔材料。平面结构的芳香基团具有较大的空间位阻以及pi-pi偏移堆积作用,而多酰胺基团间还能形成多重氢键。这些因素的共同作用能大大提高聚乙炔螺旋结构对于温度和极性溶剂的稳定性。我们还将系统研究此类聚乙炔材料侧基空间位阻、多重氢键作用、pi-pi偏移堆积作用、手性中心、手性/非手性组分变化、温度变化、溶剂极性对于聚合物螺旋结构、螺旋方向以及稳定性的影响。建立聚乙炔材料分子结构、外部刺激同其螺旋构象之间的关系。总结归纳调控此类聚乙炔螺旋结构及螺旋方向的规律。这对于高稳定性螺旋聚乙炔的制备和应用将具有重要意义。
中文关键词: 聚乙炔;偶氮苯;芴;螺旋结构;稳定性
英文摘要: The helical structures of most substituted polyacetylenes were very unstable under high temperature or in polar solvents, and therefore the application of this kind of helical polyacetylenes was limitted greatly. In this project, a series of bulky and planar aromatic gourps, amidic groups and chiral centers will be introduced into aceylene molecules. These substituted aceylenes will be polymerized into a series of new high stable helical polyacetylenes. The helical structures will be stablized by the combined action of steric repulsion, hydrogen-bond interaction and offset pi-pi staking greatly. As we know, there are bulky steric repulsion and offset pi-pi staking between planar aromatic rings. There also exists hydrogen-bond interaction between amidic groups, and the multiple hydrogen-bond interaction significantly improves the stability of superamolecular structures than mono hydrogen-bond interaction. Consequently, the pendant groups containing planar aromatic gourps and multiple amidic groups will greatly improve the stability of helical structure under high temperature and in polar solvents. In addition, we will also systematically study the relationship between the helical structure and influence factors, such as steric repulsion, multiple hydrogen-bond interaction, pi-pi offset stacking, chiral center, ch
英文关键词: polyacetylene;azobenzene;fluorene;helical structure;stability