Processing-Structure-Property Relationship in the Fabrication of Hybrid Nanostructured Materials with Tunable Architecture

该奖项的研究目标是研究有机-无机杂化纳米结构材料的制备，在保持组成相的单独性质的同时，在复合材料的组成相之间产生强烈的粘合或结合。该制备过程包括在高压的帮助下沿碳纳米管的轴向直接成核和生长聚合物纳米晶。这些聚合物纳米晶是纳米复合材料中纳米管和基质相之间强烈结合的原因。此外，通过控制结晶压力和液体过冷度或聚合物熔体冷却到其平衡结晶温度以下的程度，该制造还将提供在不同长度尺度上调节杂化结构的结构形态的能力。具有预测能力的热力学模型将被开发用于广泛的纳米颗粒-聚合物系统，并将基于热力学驱动的聚合物晶体-纳米颗粒界面的化学相互作用。这项研究的成功完成将为各种应用的压力诱导杂化纳米材料的制备提供通用的指导方针。在碳纳米管上直接成核聚合物晶体的一个重要优点是在碳纳米管用于制备杂化纳米复合材料之前，不需要对碳纳米管的表面或官能化进行修饰。因此，未经修饰的碳纳米管将保持其非凡的电学、光学和机械性能，并且当少量存在时，其全部潜力可以被实现。这方面将对下一代光伏和数据存储设备的开发特别感兴趣。此外，聚合物纳米晶直接成核法将克服组成相间粘附性强的技术障碍，从而为制备高性能材料开辟了一条新的途径。对含纳米颗粒聚合物在压力诱导成核条件下加工的认识和实现的融合，对储罐中的屏障衬里和航空航天中用于低温燃料储存的燃料衬里等应用具有深远的影响。

The research objective of the award is to study the fabrication of organic-inorganic hybrid nanostructured materials in such a way as to create strong adhesion or bond between the constituent phases of a composite, while retaining the individual properties of the constituent phases. The fabrication process involves direct nucleation and growth of polymer nanocrystals along the axis of carbon nanotubes with the help of high pressure. These polymer nanocrystals are responsible for the strong bond between the nanotube and the matrix phases in the nanocomposite. Furthermore, the fabrication will also provide the ability to tune the structural morphology of the hybrid structure at different length-scales by controlling the crystallization pressure and liquid undercooling or the degree to which the polymer melt is cooled below its equilibrium crystallization temperature. Thermodynamic models with predictive capabilities will be developed for a wide range of nanoparticle-polymer systems and will be based on thermodynamically-driven chemical interactions at the polymer crystal-nanoparticle interface. Successful completion of the research will provide generic guidelines governing pressure-induced fabrication of hybrid nanostructured materials for a variety of applications.An important advantage of direct nucleation of polymer crystals on carbon nanotubes is to eliminate the need to modify the surface or functionalization of carbon nanotubes prior to their use in the fabrication of hybrid nanocomposites. Thus, the un-modified carbon nanotubes will retain their extraordinary electrical, optical, and mechanical properties and their full potential, when present in small amounts, can be realized. This aspect will be of particular interest in the development of next generation of photovoltaic and data storage devices. Moreover, the direct polymer nanocrystal nucleation method will overcome the technological barrier of obtaining strong adhesion between the constituent phases and thereby will open-up a new avenue for fabricating high performance materials. The confluence of understanding and the realization of processing of polymers containing nanoparticles under pressure-induced nucleation conditions have far reaching impact in applications such as barrier liners in storage tanks and fuel liners for cryogenic fuel storage in aerospace.