Graphene-enhanced natural fiber reinforced composites for protective footwear and other high-performance applications

安全鞋的设计是为了保护工人的脚不受伤害，如被锋利的物体刺伤脚底，以及因重物坠落而压碎/摔断脚。直到最近，安全鞋还主要是钢制的。然而，钢制安全鞋的结构很重，靴子的重量很大，导致运动受限，长时间轮班的工人也很累。因此，由标准合成纤维材料(碳、玻璃或芳纶)制成的纤维增强聚合物复合材料(FRP)现在正成为传统钢鞋的流行替代品。这是由于其优越的高刚度和高强度以及低重量特性。然而，随着全球环境问题的急剧上升，迫切需要找到更可持续的FRPS制造方法，以实现净零排放和最小限度地使用不可再生资源。天然纤维增强复合材料(NFRP)作为合成纤维增强复合材料的轻质、环境友好的替代品正在兴起。尽管天然纤维具有与合成纤维相当的性能，但由于纤维的亲水性，使用天然纤维作为增强材料的一个主要限制是与聚合物基质的相容性差，从而导致最终复合材料的整体力学性能较低。近年来，石墨烯及其衍生物以其优异的力学性能增强潜力引起了人们的关注。含少量石墨烯的纳米材料表面处理后，NFRPS的力学性能显著提高。然而，到目前为止，还没有系统地了解这些复合材料的工艺-结构性能关系，以及如何在不同的加载和使用条件下优化这些复合材料。这项拟议的研究旨在开发用于安全鞋类的耐用轻质混杂复合材料，该复合材料由NFS和石墨烯颗粒增强。我们将探索不同的石墨烯材料、聚合物基质和复合加工条件，以实现符合CSA安全要求的可持续轻质防护鞋的优化设计，同时显著提高加拿大工人的舒适度。

Safety footwear is designed to protect workers' feet against injuries such as sole puncture by sharp objects and crushed/broken feet by falling of heavy objects. Until recently, safety shoes were predominantly made of steel. Nevertheless, steel safety shoes present a heavy construction, with significant weight of the boots resulting in motion restriction, and tiredness of workers with long work shifts. For this reason, fiber reinforced polymer composites (FRPs) made from standard synthetic fiber materials (Carbon, Glass or Kevlar) are now becoming a popular alternative to traditional steel shoes. This is due to the superior high stiffness and strength and low weight properties. However, with the steep rise in global environmental concerns, there is a dire need to find more sustainable ways of manufacturing of FRPs to achieve Net-Zero emissions and minimal use of non-renewable resources. Natural fiber reinforced composites (NFRPs) are emerging as light-weight, environmentally friendly alternatives to the synthetic fiber reinforced composites. Although natural fibers (NFs) exhibit comparable properties to their synthetic counterparts, a main limitation of using NFs as reinforcements is the poor compatibility with polymer matrices due to the hydrophilic nature of the fibers, thus leading to low overall mechanical properties of the final composites. Recently, graphene and its derivatives have attracted attention for their outstanding mechanical properties enhancement potential. Surface treatment of NFs with small percentages of graphene-based nanomaterials has shown a significant increase in the mechanical behavior of NFRPs. However, to date, there is no systematic understanding of the process-structure property relationship and how to optimize these composites for various loading and in-service conditions. The proposed research aims to develop durable lightweight hybrid composites reinforced with NFs and graphene-based particles for safety footwear. We will explore different graphene materials, polymer matrices and composite processing conditions to achieve optimal design of sustainable lightweight protective shoes that meet the CSA safety requirements while significantly improving the comfort levels of Canadian workers.