天然木材的功能化及其应用进展

Advances in Functionalization and Application of Natural Woods

现代工业和经济的快速发展消耗了大量的石油及石油基材料,导致碳排放问题日益凸显,并使生态环境污染问题越发严重。开发并利用各种绿色的生物质功能材料以部分代替通过石油衍生而来的聚合物基材料是解决该问题的有效应对措施之一。天然木材作为一种重要的可再生资源,具有来源丰富、价格便宜且对环境友好的特点,其功能化符合可持续发展理念并在多个领域展现出巨大的应用潜力,引起了国内外科研工作者的密切关注。木材本身主要由纤维素、半纤维素和木质素组成,并具有层次分明、构造有序的多尺度分级结构。独特的分级多孔结构及其各向异性不仅可以实现木材自身营养物质和水分的运输,还为其功能化设计提供了良好的基础。近年来,研究者们通过化学洗涤、冷冻干燥、表面改性、高温碳化等手段对天然木材进行功能化,以赋予其超疏水性、光热转换能力、光学透明性、导电性等,制得具有功能性的木材基材料,大大提高了木材的产品附加值,并进一步拓宽了木材的实际应用领域。本文首先介绍了天然木材的结构和成分,然后综述了近年来木材功能化及其在油水分离、海水淡化、节能建筑、柔性电子等领域中的应用进展,最后总结了目前天然木材功能化及应用所面临的一些技术难题,并对其未来的发展方向及前景进行了展望。

The prosperity of modern industry and economy consumes a large amount of petroleum and petroleum-based materials,leading to the increasingly serious carbon emission and the deterioration of ecological environment.The exploration and utilization of various biomass functional materials to partially replace the polymer materials derived from petroleum have been considered as one of effective solutions to solve the problem.As a kind of important renewable resource,natural wood has the characteristics of rich source,low price and environmental friendliness.The functionalization accords with the concept of sustainable development,and shows great practical potentials in many fields,which has attracted close attention of domestic and abroad researchers.The wood is mainly composed of cellulose,hemicellulose and lignin,possessing a hierarchical porous structure with pronounced anisotropy.The unique hierarchical structure not only realized the efficient transports of nutrients and water,but also endowed the material with good basis for functionalization design.In recent years,many researchers have devoted to the functionalization of natural wood mainly by the means of chemical washing,freeze-drying,surface modification and high-temperature carbonization,endowing it with superhydrophobicity,photo-thermal transformation capability,optical transparency,conductivity and so on.The fabricated wood-based materials with different functions not only greatly increase the additional value of the natural wood,but also further broaden their practical applications.In this paper,the structure and composition of natural wood are firstly introduced.Secondly,the progress in the functionalization of natural woods is reviewed,and the applications in the fields of oil-water separation,seawater desalination,energy-saving building and flexible electronics are summarized.Finally,the existing technical problems in the functionalization and application of natural woods are pointed out and the future development directions are also prospected.