NANOCOMP: Integrated Hybrid Computational and Experimental Design and Processing of Polymer Nanocomposites

该补助金的主要目标是开发聚合物纳米复合材料加工的综合混合计算和实验方法，以期开发具有定制功能结构和性能的材料。热塑性聚合物纳米复合材料是最有前途的新一代材料之一，具有潜在的高导热性和导电性，机械性能和改善的阻隔性能。然而，为了实现其所承诺的潜力，仍然需要克服在加工时对其结构发展的理解以及与最终产品性质的对应关系方面存在的差距。在实验上，这项研究将是基于以下的能力，即通过一种新的样品收集装置，允许小样品量被收集在任何点沿着挤出机机筒，除了一个在线旋转流变仪的挤出机内加工后的材料的形态和流变演变。在计算方面，这项研究将侧重于开发斯托克斯动力学和耗散粒子动力学软件代码，这些软件代码可以在真实的工艺环境中准确模拟流动条件下复杂材料中纳米粒子分散体的流变学和结构特性。如果成功，本研究可望为预测真实的聚合物在热塑性聚合物纳米复合材料中的最终分散状态和取向状态提供理论依据混合顺序作为流动条件和纳米颗粒特性的函数。而且，它将提供不仅生产具有更好的总体性能而且还具有沿其横截面或表面沿着不同的机械、热、电或磁性能的部件的能力，即，以解决应该将什么材料结构和处理条件应用于部件的每个部分以产生最终期望的性能的逆向工程问题。这些部件的潜在长期应用包括电磁屏蔽、差分隐身特性、改进弹道学和轻质复合结构等。

The main objective of this grant is to develop an integrated hybrid computational and experimental methodology of polymer nanocomposite processing, with a view to enable the development of materials with tailored functional structure and properties. Thermoplastic polymer nanocomposites are among the most promising new-generation materials, with potential high thermal and electrical conductivities, mechanical performance and improved barrier properties. In order to fulfill their promised potential, however, existing gaps in the understanding of their structure development upon processing and the corresponding relationships with the final product properties still need to be overcome. Experimentally, this research will be based on the capability to follow the morphology and rheological evolution of the materials upon processing inside the extruder by means of a novel sample collecting device that allows small sample quantities to be collected at any point along the extruder barrel, in addition to an on-line rotational rheometer. Computationally, this research will focus on the development of Stokesian Dynamics and Dissipative Particle Dynamics software codes that can simulate accurately the rheological and structural properties of nanoparticle dispersions in complex materials under flow, in real process environments.If successful, it is expected that this research will allow the prediction of the final state of dispersion and orientation of thermoplastic polymer nanocomposites for real polymer compounding sequences as a function of flow conditions and nanoparticle characteristics. Also, it will provide the capability to not only produce parts with better overall properties, but also with differential mechanical, thermal, electrical or magnetic properties along their cross section or surface, i.e., to solve the inverse engineering problem of what material architecture and processing conditions should be applied to each section of the part to yield the final desired properties. Potential long-term applications of these parts include, among others, electromagnetic shielding, differential stealth characteristics, improved ballistics and lightweight composite structures.