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

以嵌段共聚物自组装为模板的磁性氧化物纳米颗粒

• 批准号: 0347319
• 负责人: Peter Kofinas
• 金额: --
• 依托单位: University of Maryland, College Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2004
• 资助国家: 美国
• 起止时间: 2004-10-01 至 2008-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0347319&HistoricalAwards=false
• 关键词: Magnetic; Oxide; Nanoparticles; Templated; Self

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.

CTS-0347319P。马里兰大学学院公园分校的科菲纳斯对先前获得的职业奖提出的更新提案的目的是将半金属纳米颗粒纳入微相分离二嵌段共聚物的自组装域中，并合成表现出改善的磁性的球形和圆柱形功能纳米结构。 降冰片烯及其衍生物的开环复分解聚合（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，将无机材料的纳米颗粒限制在纳米域之一内。 嵌段共聚物中域结构的自组装性质可以控制10-500埃纳米粒子的形状、尺寸和分散性。我们计划在受控条件下仔细合成块状和薄膜形式的特定聚合物模板纳米复合材料家族，建立它们的结构、化学化学计量和有序度，然后将磁性特性与结构化学参数相关联。 传统和磁中子散射的独特组合将用于建立聚合物自组装和磁性之间的关系，该关系将针对将被纳入自组装聚合物纳米域（包括已知的半磁体）的广泛铁磁体进行。金属体系如 CrO2、尖晶石如 NiFe2O4 和层状铁氧体如 Ba2Fe6O19。拟议研究的更广泛影响涉及纳米系统中的磁性，这是基础科学中一个令人着迷的话题，由于磁铁是电子设备的重要组成部分，因此它也与微电子领域最先进技术的进步密切相关。 随着微电子系统的尺寸不断缩小以及对小尺寸元件的需求增加，理解和控制小长度磁体（例如纳米粒子）的磁特性变得越来越重要。 纳米晶氧化物尖晶石对于磁特性的基础研究很有意义，磁特性在高频器件、存储核心和磁记录介质中都有广泛的应用。这项研究的追求将导致新一代本科生和研究生的培训，并建立该领域的研究基础设施对聚合物和微电子行业的未来技术发展至关重要。 即将开展的教育活动包括本科生和研究生教学、研究生咨询、本科生研究参与和指导的各种机会，以及交互式网页的开发。 中学教师和学生还将通过 RET 和 REU 补充剂接触纳米粒子研究的各个方面，如果该提案获得资助，将要求提供这些补充剂。