CAREER: The Synthesis of New Polymers and Materials using Living Polymerizations: Well-Defined Hybrid Organic/ Inorganic Nanoparticles

模式纳米团簇由于其独特的尺寸依赖性质以及因此具有的技术应用潜力而引起了人们的广泛关注。利用纳米团簇特性的下一个重要步骤是将它们整合到成膜材料中并进行排序。首席研究员将研究制备定义良好的混合无机/有机纳米颗粒的方法，其中核心是（半）金属氧化物纳米团簇，外层是乙烯聚合物，如聚苯乙烯，聚甲基丙烯酸甲酯和聚丙烯酸甲酯。特别是二氧化硅，将被研究用于方法开发的目的，然后这些方法将被应用于其他（半）金属氧化物纳米团簇显示磁性和光学性质。该项目将首先研究将活性自由基聚合引发剂附着在纳米团簇表面的方法，然后使用这些表面修饰的纳米团簇作为这种聚合的引发剂。预期的产品材料将是具有从表面接枝的定义良好的聚合物链的纳米簇核。由于活聚合将用于接枝聚合物链，聚合物臂的结构和组成成为研究聚合物膜内纳米团簇排序方法的工具。因此，首席研究员将开发使用活性自由基聚合制备的聚合物的末端功能化方法。一种提出的方法涉及乙烯基单体与环烯酮缩醛的嵌段共聚，然后水解以产生羧酸端聚合物。这些末端功能化方法将用于在纳米星形聚合物的表面链端放置各种官能团。从纳米团簇表面接枝嵌段共聚物也将被研究。研究人员将研究所得的星团c聚合物的微相分离行为，以确定纳米团簇是否可以使用这种策略在聚合物薄膜内有序排列。首席研究员将把这些研究成果与加州大学戴维斯分校将聚合物科学纳入化学课程的教育目标结合起来。由于大多数美国主要化学品生产商在聚合物和聚合物材料方面都有重大的商业努力，化学专业的学生很有可能进入聚合物研究、开发和制造领域。因此，在课程中增加这门学科将为学生提供宝贵的培训和技能，这将提高他们在竞争日益激烈的化学就业市场中的就业前景。＊＊＊

9733786 Patten Nanoclusters have garnered much interest due to their unique size- dependent properties and, consequently, their potential for technological applications. The next important step in exploiting the properties of nanoclusters is their incorporation into and ordering within film-forming materials. The principal investigator will study methods to prepare well-defined hybrid inorganic / organic nanoparticles in which the cores are (semi)metal oxide nanoclusters and the exterior layers are vinyl polymers, such as polystyrene, poly(methyl methacrylate) and poly(methyl acry ate). In particular, silica, will be studied for the purposes of methods development, and then these methods will be applied to other (semi)metal oxide nanoclusters exhibiting magnetic and optical properties. This project will initially investigate methods to attach initiators for living radical polymerizations to the surfaces of the nanoclusters and then use these surface-modified nanoclusters as initiators for such polymerizations. The anticipated product material will be a nanocluster core with well-defined polymer chains grafted from the surface. Because living polymerizations will be used to graft the polymer chains, the structure and composition of the polymer arms become a tool to investigate methods for ordering the nanoclusters within the polymer film. The principal investigator will therefore develop methods for the end- functionalization of polymers prepared using living radical polymerizations. One proposed method involves the block copolymerization of vinyl monomers with cyclic ketene acetals followed by hydrolysis to yield carboxylic acid-terminated polymers. These end-functionalization methods will be used to place a variety of functional groups at the surface chain ends of the nanocluster star polymers. The grafting of block copolymers from the surfaces of nanoclusters will also be studied. The microphase separation behavior of the resulting starblock c opolymers will be exarnined to determine whether nanoclusters can be ordered within polymer films using this strategy. %%% The principal investigator will integrate these research efforts with the educational goal of incorporating polymer science into the chemistry curriculum at UC Davis. Because most of the major US chemical producers have significant business efforts in polymers and polymeric materials, chemistry students have a high probability of moving into careers in polymer research, development and manufacturing. Thus, the addition of this subject to the curriculum will provide students with valuable training and skills that will enhance their employment prospects in an increasingly competitive chemistry job market. ***