摘要
轻木(Ochroma pyramidale)是一种天然生物质材料,具有成本低廉、含量丰富、可再生、可生物降解等优势,还具有密度低、质量轻、孔隙度高、生长速度快等特点。除此之外,它还具备多孔、层次化的物理结构,且尺寸稳定性好、容易加工。近年来,利用这些优点,采用简单有效的自上而下的处理方法,如细胞壁膨化、干燥等步骤,可以得到一种比表面积大、孔隙率高、力学性能优异且具备可调多级孔结构的海绵状材料。这种结构与传统气凝胶多孔道结构以及海绵的结构非常相似,因此将其称为气凝胶型轻木,也称为木海绵(WS),它不仅能克服传统气凝胶力学性能差、制备过程复杂、能源消耗高、环境友好性差等缺陷,而且通过一系列功能化处理,可被赋予多种新的功能,进而用于制备可生物降解的气凝胶型复合材料,并且有助于缓解能源危机和环境污染问题,这使得轻木成为现阶段生物基气凝胶型复合材料研究者的新宠。本文从天然轻木的微观构造及化学成分出发,介绍了生物基气凝胶型轻木基复合材料的特点,归纳了其制备方法,详述了其现阶段在油水分离、透明材料、储能材料等领域的研究进展,最后针对气凝胶型轻木基复合材料在制备和应用等方面存在的问题提出了建议,以期为气凝胶型轻木的高附加值利用提供理论参考。
Balsa wood(Ochroma pyramidale),as a kind of natural biomass raw material,is low cost,naturally abundant,renewable and biodegradable,and it also has lots of advantages,including low density,light quality,high porosity and thin cell walls.In addition,it also has a porous hierarchical physical structure,good dimensional stability and easy processing.In recent years,researchers have found that a sponge-like material with large specific surface area,high porosity,excellent mechanical properties and adjustable multistage pore structure could be obtained using these advantages,through a simple and effective top-down processing method,such as cell swelling and drying.This structure is very similar to the traditional aerogel and sponges,so it is called aerogel-type balsa wood,also known as wood sponge(WS).Moreover,through a series of subsequent functionalization,it could be endowed with a variety of new functions,and then be used to prepare biodegradable aerogel-type composite materials.At the same time,this material could overcome some defects of traditional aerogels,such as poor mechanical properties,complicated production process,high energy consumption and non-environmental regeneration,making them ideally suited for the research of various functional materials.In this review,we highlight the micro/nanostructures of balsa wood and aerogel-type balsa,briefly introduce the characteristics of bio-based aerogel-type balsa wood-based composite materials,and summarize the preparation methods.The latest advances in oil/water separation,transparent materials,energy storage materials and other fields are also described.Furthermore,the scientific and technical challenges and future research opportunities are finally discussed,providing a theoretical reference for the high value-added utilization of aerogel-type balsa wood.
作者
刘颖
黄艳辉
刘贤淼
LIU Ying;HUANG Yanhui;LIU Xianmiao(College of Materials Science and Technology,Beijing Forestry University,Beijing 100083,China;International Bamboo and Rattan Center,National Forestry and Grassland Administration,Beijing 100102,China)
出处
《材料导报》
EI
CAS
CSCD
北大核心
2022年第15期199-207,共9页
Materials Reports
基金
林业公益性行业科研专项经费(201504610)。
关键词
天然轻木
木海绵
气凝胶型复合材料
自上而下
功能化改性
natural balsa wood
wood sponge
aerogel-type composite material
top-down
functionalization modification
