Macroparticle Self-(de)Assembly: Using Janus Beads to Control Cohesive Mixing/Segregation of Fine Particles

摘要提案号：cts -0553763首席研究员：McCarthy， Joseph j .隶属机构：匹兹堡大学使用Janus微珠控制细颗粒的内聚混合/分离知识价值良好的颗粒混合的主要障碍在于这样一个事实，即颗粒即使在大小、密度等方面略有不同，也容易分离，或表现为“不混溶”材料，而人们对限制这种分离趋势知之甚少。这项工作的目的是解决细颗粒的混合和分离的控制，提出的工作直接类比于处理正弦粒子系统时不混溶液体的处理。该项目将使用两亲性颗粒——有时被称为“Janus珠”——作为干表面活性剂，以显著改善对细粉末混合的控制。不像在l系统中通过改变间隙流体直接操纵二元粒子间力那样，将使用一种辅助成分来调节二元相互作用，以使其有利。此外，与液-液萃取类似，相反的情况也是可能的：可以使用定制的颗粒作为萃取剂来分离通常倾向于混合的颗粒。该项目将导致引入新的两亲性颗粒生产方法；适用于10-250-m尺寸范围内定制颗粒的拉脱力光学表征技术的开发和验证；开发了一种经过测试和验证的内聚混合理论，用于预测间隙液体和表面力对粉末行为的影响；以及一种潜在的商业上可行的新颗粒处理应用技术的可用性，分别使用干表面活性剂和颗粒萃取器进行混合和分离。更广泛的影响这项工作的更广泛的影响在于加强基础设施，整合教学和研究，以及培养研究生（重点是代表性不足的群体）。在项目过程中，将为一名全日制研究生提供培训。将尽一切努力从代表性不足的群体中招收学生。特别是，与两所HBCU的紧密联系——克拉克亚特兰大大学和摩根州立大学——将在招聘方面发挥作用。提出的工作将通过产生新的和潜在的商业上可行的技术来控制粒子处理行为，从而增强基础设施。

ABSTRACTProposal Number: CTS-0553763Principal Investigator: McCarthy, Joseph J.Affiliation: University of PittsburghProposal Title: Macroparticle Self-(de)Assembly: Using Janus Beads to Control Cohesive Mixing/Segregation of Fine ParticlesIntellectual MeritThe primary hindrance to good particle mixing lies in the fact that particles that differ even slightly in size, density, etc. easily segregate, or behave as "immiscible" materials, and little is known regarding limiting this unmixing tendency. This work is aimed at addressing the control of mixing and segregation of fine particles, The proposed work makes a direct analogy to the handling of immiscible liquids when treating sine particle systems. The project will use amphiphilic particles - sometimes called "Janus beads" - as dry surfactants in order to dramatically improve control of the mixing of fine powders. Instead of manipulating the binary interparticle force directly, as is done in L-systems through changes in interstitial fluid, an additive component that mediates the binary interaction in order to make it favorable will be used. Moreover, in analogy to liquid-liquid extraction, the converse will also be possible: tailored particles may be used as extraction agents to separate particles that would normally tend to mix.The project will result in the introduction of novel amphiphilic particle production methods; the development and validation of optical characterization techniques for pull-off force applicable to tailored particles in the size range of 10-250-m; development of a tested and validated cohesive mixing theory for predicting the impact of interstitial liquid and surface forces on the behavior of powders; and availability of a potentially commercially viable technique for novel particle processing applications of mixing and segregation (separation) using dry surfactants and particle extractors, respectively.Broader Impacts The broader impacts of the work lie in enhancing infrastructure, integrating teaching and research, and training of graduate students (with emphasis on under-represented groups). During the course of the project training will be provided for one full-time graduate student. Every effort will be made to recruit students from underrepresented groups. In particular, strong ties to two HBCU's - Clark Atlanta University and Morgan State University - will be leveraged for recruiting purposes. The proposed work will enhance infrastructure through the generation of novel and potentially commercially viable techniques for controlling particle processing behavior.