Greener, cleaner, composites

本提案的总体目标是对聚合物基复合材料的加工、制造和性能有一个基本的了解，其中基体材料部分或全部来自生物基原料。此外，在此奖学金期间获得的知识将使FAC技术公司能够增加由生物基树脂制造的复合材料组件的商业化应用。环氧树脂是高性能复合材料的首选基体，因为它们具有出色的机械性能，包括高模量，高强度和良好的加工特性，例如低粘度。环氧树脂约占全球热固性树脂市场的70%。双酚A二缩水甘油醚（DGEBA）是环氧树脂中应用最广泛的单体。DGEBA主要由化石资源合成。因此，我们迫切需要探索可从可再生资源中获得的替代热固性化学品，以减少我们对化石资源的依赖和对地球的影响。近年来，人们希望变得更加环保并减少对日益减少的化石燃料供应的依赖，因此对生物材料中的树脂和纤维的兴趣激增。尽管环氧聚合物通常具有良好的机械性能，但由于固化的热固性材料中的高交联度，它们缺乏韧性。近年来，伦敦帝国理工学院的金洛克等人（Kinloch et al）的研究小组缓解了这种缺乏韧性的状况（Dr. Dallan以前是Kinloch教授的研究员）。这是通过在部件最终固化之前向树脂共混物中添加添加剂来实现的。微米级橡胶颗粒，无论是预先形成的或通过反应诱导相分离形成的，已被证明是最有效的。生物基树脂也缺乏韧性。迄今为止，尚未对生物基树脂（或含有生物基和常规石油衍生热固性材料的混合物的混合树脂）的“增韧性”进行广泛研究。“韧性”是指每加入单位添加剂，热固性聚合物的韧性增加的量。目前尚不清楚是否或如何，同样的增韧机制将适用。这些知识对于增加来自可再生原料的更环保树脂的使用绝对至关重要。未来领导者奖学金将使Dr. Reynan成为英国复合材料行业这一转变的最前沿。事实上，文献中有一些证据表明，石油衍生树脂和生物衍生树脂的混合物在固化反应过程中会自然相分离。Dr. Reichan已经证明，通过控制固化反应的速率，有可能深刻地影响相分离系统的最终微观结构。这可能意味着使用混合化石和生物衍生树脂可以提供协同效益。这将在拟议的奖学金期间进行调查。拟议的工作是多学科的性质，将在材料科学，化学和机械工程领域之间架起桥梁。此外，通过考虑树脂分子组成的影响，该研究金将从分子水平连接复合结构内的长度尺度，通过纳米级和介观纤维基质界面行为，并最终考虑复合结构本身。还将考虑确定最终微观结构的时间（或反应速率）元素。这种系统级设计方法，从分子到组件，从“锅到零件”，是一个真正的创新理念，在工业中，将使FAC技术更好地设计复合材料结构使用越来越少的材料，同时提取更多的功能，从结构和定位博士。

The overall aim of this proposal is to develop a fundamental understanding of the processing fabrication and performance of polymer based composites where the matrix material is either partially or wholly derived from bio-based feedstock. Moreover, the knowledge gained during this Fellowship will allow FAC Technology to increase commercial uptake in composite components manufactured from bio-based resin.Epoxy resin is the matrix of choice for high-performance composites due to their outstanding mechanical properties, including high modulus, high strength and favourable processing characteristics, e.g. low viscosity. Epoxy accounts for approximately 70% of the thermoset resin market worldwide. Diglycidylether of bisphenol A (DGEBA) is the most widely used monomer to formulate epoxy resins. DGEBA is mostly synthesised from fossil resources. Thus, there is clearly a pressing need to explore alternative thermoset chemistry that can be derived from renewable resources to reduce our dependence on fossil resources and our impact on the planet.Interest in resin and fibres derived from biological materials has surged in recent years, fueled by a desire to become more environmentally friendly and reduce dependence on dwindling fossil fuel supplies. Although epoxy polymers have generally good mechanical properties, they suffer from a lack of toughness due to the high degree of crosslinking in the cured thermoset. This lack of toughness has been alleviated in recent years by groups such as Kinloch et al at Imperial College London (Dr. Carolan was previously a Fellow with Prof. Kinloch). This is achieved by adding additives in to the resin blend before final cure of the component. Micron scale rubber particles, either preformed or formed via reaction induced phase separation have proven to be most effective. Bio-based resins also suffer from lack of toughness. To date, no extensive study on the 'toughenability' of bio-based resins (or hybrid resin containing a mixture of bio-based and conventional petroleum derived thermosets) has been carried out. 'Toughenability' refers to the amount by which the toughness of a thermoset polymer increases per unit additive added. It is currently unknown whether, or how well, the same toughening mechanisms will apply. Such knowledge is absolutely critical to increase the usage of more environmentally friendly resins from renewable feedstocks. The Future Leaders Fellowship will enable Dr. Carolan to be at the forefront of this transition in the UK composites industry.Indeed, there is some evidence in the literature to suggest that blends of petroleum derived resins and bio-derived resins will naturally phase separate during the curing reaction. Dr. Carolan has already demonstrated that by controlling the rate of the curing reaction, it is possible to profoundly influence the final microstructure of a phase separated system. This potentially means that the use of hybrid fossil- and bio-derived resins may offer synergistic benefits over the other. This will be investigated during the proposed Fellowship.The work proposed is multi-disciplinary in nature and will bridge the fields of materials science, chemistry and mechanical engineering. Moreover, by considering the effect of the molecular makeup of a resin, the Fellowship will bridge the length scales within a composite structure from the molecular level, through to the nanoscale and mesoscopic fibre-matrix interface behaviour and finally considering the composite structure itself. The element of time (or reaction rate) in determining the final microstructure will also be considered. This system level design approach, from molecule to component and from 'Pot to Part', is a truly innovative idea in industry and will allow FAC Technology to better design composite structure using less and less material while extracting ever more functionality from the structure and position Dr. Carolan as one of the industry leaders in composite materials in the UK.