Development of graphene and boron nitrate-based polymeric systems for electrical applications

这项研究计划的总主题是开发基于聚合物的电气应用系统。几十年来，功能性介电和半导电性聚合物材料确实被用于电力应用。这些应用从电力电缆、高压电容器、大型旋转机械的绝缘壁的绝缘材料，到导体和绝缘屏蔽层和外电晕保护涂层的半导体材料，以及应力分级应用，已发现聚合物基复合材料在用作阻性应力分级材料时是有效的。这类材料还具有许多优点，如低成本、工业规模的可加工性，以及使用分子添加剂或增强纳米颗粒(通常为无机)来调整其电、机械和热性能的可能性。下一代电工设备的发展，如直流输电基础设施，在一定程度上依赖于具有特定特性的新介质系统的开发。抗空间电荷积累对于交流应用来说并不是必需的，但对于高压直流(HVDC)应用来说却是至关重要的，这是过去被完全忽略但在未来将被应用的新要求的一个例子。这项研究计划旨在研究和优化用于介电和电气应用的几种类型的聚合物纳米复合材料(PNC)的性能。这项研究计划中要研究的第一个系统是基于石墨烯的聚合物系统，由于现在可以批量生产石墨烯(实际上最大的供应商之一是一家加拿大公司)，基于石墨烯的聚合物系统现在正在慢慢成为经济上可行的纳米复合材料，这使得这种产品很容易在工业规模上以合理的成本获得。这些复合材料的应用范围很广，从浓度极低的高压直流电缆绝缘系统，到浓度在渗流阈值附近的电阻应力分级系统，再到浓度高于渗流阈值的半导体系统。与传统的炭黑负载聚合物相比，这些体系具有许多优点，但在广泛商业化的含石墨烯装置的出现之前，仍有许多开发和优化需要进行。本研究计划中将研究和优化的第二个体系是环氧硝酸硼纳米管(BNNT)体系，这些体系在许多应用中都是很有前途的材料，这些应用需要良好的绝缘性能和高导热系数之间的平衡，这通常是相互矛盾的。机器绝缘、储能电容器和干式高压电容器以及航空航天应用是这些材料系统的一些潜在利基。

The general topic of this research proposal is the development of polymer-based systems for electrical applications. Functional dielectric and semi-conductive polymer-based materials are indeed used since decades for electrical power applications. These applications extend from insulating materials for the insulation walls in power cables, high voltage capacitors, large rotating machines, to semiconducting materials for conductor and insulation screens and outer corona protection coatings, as well as for stress grading applications for which polymer-based composites have been found to be effective when used as resistive stress grading materials. This class of materials also features many advantages such as low cost, processability at the industrial scale and the possibility to tailor their electrical, mechanical and thermal properties with either molecular additives or reinforcing nanoparticles, usually inorganic. The development of next-generation electrotechnical apparatus, such as DC transmission infrastructures, relies in part on the development of new dielectric systems with specific properties. Resistance to space charge accumulation, which is not required for AC applications but critical for High Voltage DC (HVDC) applications, is an example of new requirement that was completely ignored in the past but will be relevant in the future. This research proposal will aim to investigate and optimize the properties of several types of polymeric nanocomposites (PNC) for dielectric and electrical applications. The first system that will be investigated in this research proposal is graphene-based polymeric systems that are now slowly becoming economically viable nanocomposites since mass produced graphene is now available (actually one of the biggest provider is a Canadian company) which makes this product readily available at the industrial scale at a reasonable cost. The application of these composites ranges from insulating systems for HVDC cables at very low concentration, to resistive stress grading systems at concentration in the vicinity of the percolation threshold up to semi-conductive systems for concentration above the percolation threshold. There are many advantages to these systems compared with conventional carbon black loaded polymers but there is still a lot of development and optimization needed before the appearance of widespread commercialized graphene-containing devices. The second system that will be investigated and optimized in this research program are epoxy Boron Nitrate NanoTubes (BNNT) systems that are promising material for many application where a balance of properties are needed such as good insulating properties and high thermal conductivity, which usually is contradictory. Machine insulation, energy storage capacitors and dry-type high voltage capacitors as well as aerospace applications are some potential niche for these material systems.