New Syntheses of Hyperbranched Ultrathin Grafts

该提案将采用非特异性分子识别，响应表面和多价，使接枝更快，更有效。 该化学将采用接枝化学在有机和无机基质上制备功能性的、可降解的超支化接枝物。 待制备的功能界面将全部用共价键组装。 这些共价组装将衍生自已知的反应-缩合反应如酰胺化和催化反应如从炔和叠氮化物形成三唑。 这样的接枝物将含有可以用光谱探针进一步改性的官能团，并且如此形成的界面将可用于改性常见材料如聚烯烃和金属氧化物的物理和化学性质。这一提议的智力影响是，它将展示如何以有用的合成方式利用多价的已知优点、分子识别的原理和大分子系统的响应特性。 拟议的工作将使用弱的分子间相互作用，如氢键，以本地化的试剂和催化剂的界面。 试剂的这种定位将通过增加参与键形成的试剂的相对浓度来促进接枝。 这样的效果将使嫁接更简单，更实用，在试剂方面浪费更少。 如果成功的话，这项研究将导致功能表面可以被设计成智能地促进它们自己的嫁接。 这一建议的更广泛影响是它对本科生和研究生的科学培训和教育的影响。 通常情况下，每年有2-3名来自德克萨斯州A M和其他地区的本科生参加，有些在夏天，有些在学年。 这些本科生将与2-3名研究生并肩工作。 所有学生都将在研究中发挥个人和创造性的作用，所有人都将参加地方，区域和国家会议的出版物和演讲。

This proposal will employ nonspecific molecular recognition, responsive surfaces and polyvalency to make grafting faster and more efficient. The chemistry will employ graft-on-a-graft chemistry to prepared functional, ultrathin, hyperbranched grafts on both organic and inorganic substrates. The functional interfaces to be prepared will all be assembled with covalent bonds. These covalent assemblies will be derived from known reactions - condensation reactions like amidation and catalytic reactions like triazole formation from alkynes and azides. Such grafts will contain functional groups that can be further modified with spectroscopic probes and the interfaces so formed will be useful in modification of the physical and chemical properties of common materials like polyolefins and metal oxides. The intellectual impact of this proposal is that it will demonstrate ways to use the known advantages of polyvalency, the principles of molecular recognition and the responsive character of macromolecular systems in a useful synthetic way. The proposed work will use weak intermolecular interactions like hydrogen bonding to localize reagents and catalysts at interfaces. Such localization of reagents will facilitate grafting by increasing the relative concentrations of the reagents involved in bond formation. Such effects will make grafting simpler, more practical and less wasteful in terms of reagents. If successful, this research will lead to functional surfaces can be designed so as to intelligently facilitate their own grafting. The broader impact of this proposal is its effect on the scientific training and education of students at both the undergraduate and graduate level. Typically 2-3 undergraduates from Texas A&M and outside will be involved each year, some in the summer and some during the school year. These undergraduates will work side-by-side with 2-3 graduate students. All students will have individual and creative roles in the research and all will participate in publications and presentations at local, regional and national meetings.