Magnetic Oxide Nanoparticles Templated By the Self-Assembly of Block Copolymers

CTS-0347319 P。Kofinas，马里兰州大学公园本更新建议的目的是以前获得的CAREER奖，是将半金属纳米粒子的自组装域的微相分离的二嵌段共聚物和合成球形和圆柱形的功能纳米结构，表现出改善的磁性能。 石墨烯及其衍生物的开环易位聚合（ROMP）已被证明是合成窄多分散性金属功能化嵌段共聚物的一种非常有效的方法。 嵌段共聚物微相分离可以有效地用作模板以将无机材料的纳米颗粒限制在纳米畴之一内。 嵌段共聚物中畴结构的自组装性质允许控制10-500埃纳米颗粒的形状和尺寸以及分散。我们计划在受控条件下以本体和薄膜形式仔细合成特定家族的聚合物模板纳米复合材料化合物，建立它们的结构，化学计量和有序度，然后将磁性与结构化学参数相关联。 将使用常规中子散射和磁性中子散射的独特组合来建立聚合物自组装和磁性之间的关系，将对将被并入自组装聚合物纳米畴中的广泛类别的铁磁体进行，所述铁磁体包括已知的半金属系统，例如CrO 2，尖晶石如NiFe 2 O 4和层状铁氧体如Ba 2Fe 6 O 19。所提出的研究的更广泛的影响涉及纳米系统中的磁性，这是基础科学中的一个迷人的课题，这也与微电子学中最先进技术的进步密切相关，因为磁体是电子器件的重要部件。 随着微电子系统尺寸的不断缩小和对小尺寸部件需求的增加，对诸如纳米颗粒的小长度尺度磁体的磁特性的理解和控制变得越来越重要。 纳米晶氧化物尖晶石在磁性的基础研究中具有重要的意义，在高频器件、存储器磁芯和磁记录介质中有着广泛的应用。这项研究的开展将培养新一代的本科生和研究生，并在聚合物和微电子工业的未来技术发展中建立一个至关重要的研究基础设施。 要进行的教育活动包括本科生和研究生教学，研究生咨询，并在本科生参与研究和指导的各种机会，以及互动网页的开发。 中学教师和学生也将通过RET和REU补充剂接触纳米颗粒研究的各个方面，如果该提案获得资助，将要求这些补充剂。

CTS-0347319P. Kofinas, University of Maryland College ParkThe purpose of this renewal proposal to a previously obtained CAREER award, is to incorporate half metallic nanoparticles into the self-assembled domains of microphase separated diblock copolymers and to synthesis spherical and cylindrical functional nanostructures exhibiting improved magnetic properties. Ring-opening metathesis polymerization (ROMP) of norbornene and its derivatives has proved to be a very effective way of synthesizing metal-functionalized block copolymers of narrow polydispersity. The block copolymer microphase separation can be effectively used as a template to confine nanoparticles of inorganic materials within one of the nanodomains. The self-assembled nature of the domain structure in block copolymers allows control over the shape and size and dispersion of 10-500 angstrom nanoparticles.We plan to carefully synthesize specific families of polymer templated nanocomposite compounds in bulk and thin-film form under controlled conditions, establish their structure, chemical stoichiometry, and degree of order, and then correlate the magnetic properties with the structural-chemical parameters. A unique combination of conventional and magnetic neutron scattering will be used to establish the relationship between the polymer self-assembly and the magnetic properties will be conducted for a broad class of ferromagnets that will be incorporated into the self-assembled polymer nanodomains including known half-metallic systems such as CrO2, spinels such as NiFe2O4 and layered ferrites such as Ba2Fe6O19.The broader impacts of the proposed research relate to magnetism in nanometer systems, a fascinating topic in fundamental science, which is also closely related to the advancement of the state-of-the-art technologies in microelectronics since magnets are vital components of electronic devices. As the dimension of microelectronic system continually shrinks and demands for small-dimension components increase, the understanding and controlling magnetic properties of small length scale magnets such as nanoparticles becomes increasingly crucial. Nanocrystalline oxide spinels are of interest both for fundamental studies in magnetic properties that have found numerous applications in high frequency devices, memory cores and magnetic recording media.The pursuit of this research will result in training of a new generation of undergraduate and graduate students and build research infrastructure in an area of vital importance to future technical developments in the polymer and microelectronic industries. The education activities to be undertaken include undergraduate and graduate teaching, graduate student advising, and various opportunities in undergraduate research involvement and mentoring, as well as the development of an interactive web page. Middle school teachers and students will also be exposed to aspects of nanoparticle research through RET and REU supplements, which will be requested if this proposal is funded.