Manufacturing Bio-inspired "Artificial Wood" from (Low-Cost) Ionic Liquids

目前，设计和制造用于大批量结构应用的可再生材料并使我们的经济与化石衍生的不可再生资源脱钩是一个及时的需求。基于纤维素的天然纤维是生产低成本高性能可再生复合材料的主要候选材料。然而，天然纤维增强聚合物和传统的化石衍生工程材料之间仍然存在性能差距（见图1），因为纤维素微纤维的高拉伸刚度（高达165 GPa）和强度（至少1 GPa）尚未在复合材料中得到充分利用。大自然在操纵和利用木材（一种天然复合材料）中的纤维素微纤维以生产高性能材料方面非常有效。该项目将从木材中获得灵感，并使用简单且本质上可扩展的制造概念制造世界上第一种“人造木材”，即保留天然纤维素I结构（模仿木材细胞壁）的纤维素微纤维增强木质素复合材料。拟议的研究活动围绕（一）从（低成本）离子液体中制造“人造木材”，（二）设计和制造单向和连续的“人造木材”纤维增强可再生复合材料，以及（三）优化“人造木材”制造的技术经济和生命周期。据设想，由此产生的“人造木材”将针对传统生物基聚合物或可再生天然纤维增强聚合物无法单独实现的工程应用，并可作为传统玻璃纤维增强聚合物的替代品。

There is currently a timely need to design and manufacture renewable materials for high volume structural applications and decouple our economy from fossil-derived non-renewable resources. Cellulose-based natural fibres are the prime candidate for the production of low-cost high-performance renewable composites. However, there is still a property-performance gap between natural fibre-reinforced polymers and traditional fossil-derived engineering materials (see Fig. 1), as the high tensile stiffness (up to 165 GPa) and strength (at least 1 GPa) of cellulose microfibrils have yet to be fully exploited in a composite setting. Nature has been very efficient at manipulating and exploiting cellulose microfibrils in wood (a natural composite) to produce high performance materials. This project will take inspiration from wood and manufacture the world's first "artificial wood", i.e. cellulose microfibril-reinforced lignin composites with the native cellulose-I structure preserved (mimicking wood cell wall), using simple and intrinsically scalable manufacturing concepts. The proposed research activities are structured around (i) manufacturing "artificial wood" from (low cost) ionic liquid, (ii) design and manufacture of unidirectional and continuous "artificial wood" fibre-reinforced renewable composites and (iii) optimising the techno-economics and lifecycle of "artificial wood"manufacturing. It is envisaged that the resulting "artificial wood" will target engineering applications that cannot be achieved by conventional bio-based polymers or renewable natural fibre-reinforced polymers alone and could serve as alternative to traditional glass fibre-reinforced polymers.