Materials World Network: Study of Macromolecular Ferrofluids

高分子铁磁流体研究的材料世界网络汇集了一个由化学家，物理学家和工程师组成的国际团队，以解决纳米结构聚二甲基硅氧烷（PDMS）铁磁流体的设计，合成和性能，并研究控制其液滴在亲水，不混溶，粘性介质中的磁泳流动性。 该团队包括J. S。Riffle和R. M.戴维斯，部门。化学和化学工程，VA Tech，Blacksburg，VA，USA和T. G.圣皮埃尔和R. C.伍德沃德，物理学院，M。A. Saunders，西澳大利亚大学显微镜和微量分析中心，珀斯，Au。最终目标是利用梯度磁场来操纵疏水性磁性液滴通过水性介质，并对液滴施加力。 在磁场梯度的影响下，磁流体液滴在不互溶粘性介质中的运动和行为是复杂的。 为了获得对所施加的磁场和场梯度的最佳响应，需要对铁磁流体粘度、表面张力、磁化率和液滴尺寸进行最佳设计。 这些参数由分子组成、纳米颗粒尺寸、分散剂和载体分子量、在具有和不具有磁场的液滴内的分散特性、流体和介质之间的界面张力以及复杂的流体性质决定。 定义明确的PDMS-磁铁矿纳米颗粒复合物将被制备和分散在PDMS载体中，有和没有特殊的嵌段共聚物表面活性剂的帮助下，以了解它们的结构-性能关系。 一个潜在的应用是使用生物相容性PDMS铁磁流体从眼睛内部向脱离的视网膜施加磁力，以将其压入下方脉络膜的适当位置，并且还闭合视网膜中的孔。 纳米结构的铁磁流体在生物技术中还有其他潜在的应用，例如磁场导向的药物载体，用于动脉瘤远程治疗的流体，或用于暂时关闭纳米至微米尺寸开口的液体球阀。 研究成果也有望成为铁磁流体驱动器、电磁微泵、流体阀门和密封系统。 研究生和本科生将接受团队合作技能和创造力的培训，以在全球范围内解决复杂的多学科研究问题。 该奖项由国际科学与工程办公室的东亚太平洋计划共同资助。

The Materials World Network for the Study of Macromolecular Ferrofluids brings together an international team of chemists, physicists and engineers to address the design, synthesis and properties of nanostructured polydimethylsiloxane (PDMS) ferrofluids, and to investigate control over the magnetophoretic mobility of their droplets in hydrophilic, immiscible, viscous media. The team includes J. S. Riffle and R. M. Davis, Depts. of Chemistry and Chemical Engineering, VA Tech, Blacksburg, VA, USA and T. G. St. Pierre and R. C. Woodward, School of Physics, and M. A. Saunders, Center for Microscopy and Microanalysis, the University of Western Australia, Perth, AU.The ultimate goals are to employ gradient magnetic fields to maneuver hydrophobic magnetic droplets through aqueous media, and to apply forces with the droplets. The motion and behavior of ferrofluid droplets in an immiscible viscous medium under the influence of magnetic field gradients are complex. To obtain optimal response to applied magnetic fields and field gradients requires optimal design of ferrofluid viscosity, surface tension, magnetic susceptibility, and droplet size. These parameters are determined by the molecular compositions, nanoparticle sizes, dispersant and carrier molecular weights, dispersion characteristics within the droplets with and without a magnetic field, interfacial tension between the fluid and the medium, and the complex fluid properties. Well-defined PDMS-magnetite nanoparticle complexes will be prepared and dispersed in PDMS carriers, with and without the aid of special block copolymer surfactants, to understand their structure-property relationships. One potential application is the use of biocompatible PDMS ferrofluids for applying a magnetic force from inside the eye on a detached retina to press it into place against the underlying choroid, and also to close a hole in the retina. There are also other potential applications of nanostructured ferrofluids in biotechnology such as magnetic field-directed drug carriers, fluids for remote treatment of arterial aneurysms, or liquid ball valves for temporarily closing nanometer to micron size openings. The outcomes of the research are also expected to have potential as ferrofluid-based actuators, electromagnetic micropumps, and fluid based valves and sealing systems. Graduate and undergraduate students will be trained with the teamwork skills and the creativity for tackling complex multi-disciplinary research problems in a global setting. This award is co-funded by the East Asia Pacific Program of the Office of International Science and Engineering.