Engineering with Graphene for Multi-functional Coatings and Fibre-Composites

石墨烯是一种包含单层碳原子的材料，但颗粒可以具有潜在的毫米范围内的线性尺寸。它具有一系列显着的特性，当添加到聚合物材料中时，这些特性提供了潜在的好处，包括增韧，导电性，自润滑性和阻燃性。石墨烯固有的二维几何形状有优点和缺点;具体来说，它将我们引向薄层应用，例如用于最能利用其几何形状的涂层。这些应用还本质上需要相对少量的填料以获得显著的影响，从而有效地利用最初可能可用的相对少量的石墨烯。石墨烯与现有的最先进的商业系统相结合是一个特别有前途的途径，通过增强当前材料的快速商业化。拟议研究的总体目标是展示石墨烯如何在复合工程背景下使用，以改善当前聚合物基材料的性能。关键的挑战是明确定义的石墨烯材料的分散和功能化，以及将其与选定的聚合物系统结合的联合收割机的加工路线的开发。必须避免作为缺陷的团聚物，并使与基质的化学相互作用最大化，以避免不必要的分层。天然石墨烯薄片中的应力传递的测量表明，它们必须在数十微米内保持平坦以进行有效的增强;但是明智地使用非破坏性官能化途径应该将该要求放宽至少一个数量级。优化的表面化学是在使用中与基体相互作用和有效加工真正膨胀石墨的关键。我们将利用我们特定的，可扩展的，内部路线来功能化，分散的石墨烯，最大限度地减少框架损伤。因此，第一个挑战是以可扩展的方式生产具有正确功能的石墨烯，以确保与所用基质的良好相容性和最佳性能改善。该团队已经确定了两条潜在的路线，由于我们不知道哪条路线最有效，我们将对这两条路线进行调查。这些改性的石墨烯将以百分之几的适度负载量与基质组合，以产生足以在下述应用中为功能涂层提供益处的优化复合系统。另一个基本方面是有机会产生高石墨烯含量的复合材料，并控制石墨烯在结构形成中的分布，所述结构被设计成利用其独特的固有性质。为了应对这一挑战，我们将开发三种替代路线来制造大面积石墨烯薄膜;这些系统提供了一种更激进的方法，以实现更大的潜在改进。将测量改性石墨烯和聚合物共混物的基本机械和物理性能，以确定最有前途的材料。我们将联合收割机将这些石墨烯材料与相关基质结合，特别是用于以下应用的环氧/聚酯树脂：用于复合材料部件的脱模和功能涂层，用于纤维复合材料飞机和风力涡轮机叶片的雷击保护和改善的阻隔性能;用于管网应用的坚韧，低渗透性，耐刮擦和自润滑功能涂层（包括阀门）和机械系统;以及凭借增强的阻隔性能和焦炭形成的防火涂料。

Graphene is a material comprising a single layer of carbon atoms, yet particles can have linear dimensions potentially in the millimetre range. It has a remarkable set of properties that offer potential benefits when added to polymer materials, including toughening, electrical conductivity, self-lubrication and fire retardance. The intrinsic two-dimensional geometry of graphene has pros and cons; specifically, it directs us towards applications in thin layers, such as for coatings where its geometry can best be utilised. These applications also intrinsically require relatively small quantities of filler for a significant impact, thus making efficient use of relatively small quantities of graphene that are likely to be available initially. The combination of graphene with existing state-of-the-art commercial systems is a particularly promising route to rapid commercialisation through the enhancement of current materials.The overall aim of the proposed research is to show how graphene can be used in a composite engineering context, to improve the properties of current polymer-based materials. The key challenges are the dispersion and functionalisation of well-defined graphene material, and the development of processing routes to combine it with the selected polymer systems. It is essential to avoid agglomerates that act as defects, and to maximise the chemical interaction with the matrix to avoid unwanted delamination. Measurement of stress transfer in native graphene flakes indicate that they must remain flat over many tens of microns for efficient reinforcement; but the judicious use of non-damaging functionalisation routes should relax this requirement by at least an order of magnitude. Optimised surface chemistry is the key both to interaction with the matrix in-service and to effective processing of truly exfoliated graphite. We will exploit our specific, scalable, in-house routes to functionalised, dispersed graphenes with minimised framework damage. Thus the first challenge is to produce graphene in a scalable manner with the correct functionality to ensure good compatibility with the matrices used and optimum property improvement. The team have identified two potential routes, and as we do not know a priori which will be the most effective we will investigate both. These modified graphenes will be combined with matrices at modest loadings of a few percent, to create optimised composite systems sufficient to offer benefits to functional coatings in the applications described below. A further, fundamental aspect is the opportunity to create high graphene content composites and to control the graphene distribution in the formation of structures designed to take advantage of its unique intrinsic properties. To meet this challenge, we will develop three alternative routes for the creation of large area graphene-based films; these systems offer a more radical approach to even greater potential improvements. The basic mechanical and physical properties of the modified graphene and polymer blends will be measured to identify the most promising materials. We will combine these graphene materials with relevant matrices, especially epoxy/polyester resins for the following applications: mould release and functional coatings for composite parts, lightning-strike protection and improved barrier properties for fibre-composite aircraft and wind-turbine blades; tough, low permeability, scratch resistant, and self-lubricating functional coatings for applications in pipe networks (including valves) and mechanical systems; and fire-resistant coatings by virtue of enhanced barrier properties and char formation.