Nanostructured Composite Coatings to Harden and Toughen Polymer Surfaces

由于其低密度，高韧性，易于加工和低成本，聚合物在电子，车辆，建筑材料，工业和家用电器等广泛应用中发挥着越来越重要的作用。然而，与金属和陶瓷相比，聚合物的耐划伤和耐磨性相当差。增强聚合物抗划伤/耐磨性的常用方法是在其表面添加硬涂层。然而，许多传统的硬涂层与聚合物的附着力差，容易开裂。此外，硬质涂层的传统沉积方法通常是在负压下进行的，这使得它们昂贵且难以实现大面积加工。这项工作的目标是研究一种新型的纳米结构涂层，这种涂层具有很高的抗划伤和抗裂性，并且可以用一种廉价的可扩展方法生产。这项工作的动机是最近成功地创造了基于聚合物渗透到纳米颗粒薄膜中的高浓度纳米颗粒的纳米复合涂层。这些涂层可以直接在聚合物表面形成，从而产生具有很强附着力和高抗划伤性的涂层。耐刮擦纳米复合硬涂层可作为下一代能量存储和转换设备以及光学、生物传感器和电子设备的关键部件。此外，这种材料在电子产品和食品包装中也有作为屏障的应用。该团队将开发展示复合材料特性的模块，用于为学生、教师和公众计划的外展活动。该项目将建立通过毛细管上升渗透（CaRI）将聚甲基丙烯酸甲酯（甲基丙烯酸甲酯）渗透到三水石纳米薄片薄膜中生产的砖混结构纳米复合涂层的工艺-结构-性能关系。该项目是两位研究人员的合作：李是纳米结构材料的制造、结构和光学表征方面的专家，特纳是材料和力学方面的专家。该项目将解决必须理解和克服的基本问题，以推进CaRI材料和纳米复合材料的一般领域。具体来说，空间限制对大聚合物在纳米多孔介质中的毛细管上升和运输的影响将通过改变聚合物的分子量及其相对于纳米血小板膜特征孔径的大小来研究。此外，利用CaRI工艺的通用性和可调性，将建立复合涂层的内部结构与其机械和光学性能之间的关系。通过加工、表征和建模，我们将全面了解复合材料的加工-结构-性能关系。

Owing to their low density, high toughness, ease of processing and low cost, polymers are playing increasingly important roles in a broad set of applications, including electronics, vehicles, building materials, and industrial and household appliances. Compared to metals and ceramics, however, polymers have rather poor scratch- and wear-resistance. A common approach to enhance the scratch/wear resistance of polymers is to add hard coatings on their surfaces. However, many conventional hard coatings suffer from poor adhesion to the polymer and can crack easily. Furthermore, the conventional deposition methods for hard coatings are often done under negative pressure, making them expensive and challenging to implement for large-area processing. The goal of this work is to investigate a new class of nanostructured coatings that have high scratch and crack resistance and can be produced using an inexpensive scalable method. This work is motivated by recent success in creating nanocomposite coatings with extremely high concentrations of nanoparticles based on infiltration of polymers into nanoparticle films. These coatings can be formed directly on the surface of polymers to produce coatings that have very strong adhesion and high scratch resistance. Scratch resistant nanocomposite hard coatings can potentially be used as key components of next-generation energy storage and conversion devices as well as optical, biosensors and electronic devices. Also, such materials have applications as barriers in electronics and food packaging. The team will develop modules demonstrating the properties of composite materials for use at outreach events planned for students, teachers and the general public.This project will establish the processing-structure-property relationships of brick-and-mortar structured nanocomposite coatings produced via capillary rise infiltration (CaRI) of poly(methylmethacrylate) into films of gibbsite nanoplatelets. The project is a collaboration between two investigators: Lee, an expert in the fabrication and structural and optical characterization of nanostructured materials, and Turner, an expert in materials and mechanics. The project will address fundamental issues that must be understood and overcome to advance CaRI materials and the general area of nanocomposites. Specifically, the effect of spatial confinement on the capillary rise and transport of large polymers through nanoporous media will be studied by changing the molecular weight of the polymer and its size relative to the characteristic pore size in the nanoplatelet film. Furthermore, by taking advantage of the versatility and tunability of the CaRI process, the relationship between the internal structure of the composite coatings and their mechanical and optical properties will be established. Through processing, characterization, and modeling, we will develop a holistic understanding of processing-structure-property relationship of CaRI composites.