文献类型：期刊文献

中文题名：木质导热复合材料的传热增强机理及制备研究进展

英文题名：Heat transfer enhancement mechanism and preparation technology ofwood-based thermal conductive composite

作者：陶鑫[1] 梁善庆[1] 傅峰[1]

第一作者：陶鑫

机构：[1]中国林业科学研究院木材工业研究所,北京100091

年份：2022

卷号：53

期号：2

起止页码：2057-2065

中文期刊名：功能材料

外文期刊名：Journal of Functional Materials

收录：CSTPCD;;Scopus;北大核心:【北大核心2020】；CSCD:【CSCD2021_2022】；

基金：中央级公益性科研院所基本科研业务费专项项目(CAFYBB2016MB001)。

语种：中文

中文关键词：木质导热复合材料;导热系数;浸渍;地采暖地板

外文关键词：wood-based thermal conductive composite;thermal conductivity;impregnation;wooden heating floor

分类号：TB33

摘要：木质导热复合材料是以不同几何尺度的木质单元为基体,以不同加工工艺引入导热单元后制得的一种导热性能增强的复合材料。木质导热复合材料具有较高的导热系数,可将热量迅速传递及辐射至周围环境中,若将其应用于地采暖地板、导热装饰木制品等家装领域,不仅可以充分利用天然可再生木质资源具有的质轻、易加工、经济环保等优点,减少不可再生资源的损耗,还能够实现木质材料的提质增效和高附加值利用,具有重要意义。木质材料导热性能受含水率、多孔结构及化学组分3种因素的影响,导热系数低并且呈传热各向异性。以增强传热介质、降低界面热阻、强化表面导热层为传热增强机理,木质导热复合材料的制备技术主要有浸渍处理、重组复合、表面处理3种。浸渍处理前多对木质单元碳化处理以形成完整的导热碳骨架,再浸入聚合物或导热树脂;微波膨化处理可在木质单元中形成三维网络缝隙,增加了导热单元的填充空间,适用于低熔点合金的填充凝固。重组复合技术是在单板、刨花、木纤维、木粉等木质单元中添加一定比例的导热单元与胶黏剂,通过热压成板、熔融挤出两种方法制备出木质导热复合材料。表面处理技术赋予木质基体以表面导热层,化学镀法在基体表面上沉积金属,金属中的自由电子导热能力强于木材中的声子导热。涂饰导热涂层可增强木质基体的换热能力。目前,木质导热复合材料的研究主要集中在不同导热单元的提升效果、导热单元的最佳添加量、导热性能与力学性能相适应的工艺调控上,仍停留于实验室研究阶段,尚未形成工业化生产应用。制备方法的优化、传热预测模型的构建、界面结合的增强、多重功能的拓展将是下一步研究的方向。概述了影响木质材料导热性能的因素及导热系数理论推算公式,归纳了木质导热复合材料的传热增强机理及制备方法,并展望了木质导热复合材料未来研究方向与发展前景。
The wood-based thermal conductive composite is a kind of material with enhanced thermal conductivity,which is made of wood raw materials of different scales as matrices and introduced the thermal conductive units through different processing technologies.The wood-based thermal conductive composite has high thermal conductivity,which could promptly transfer excess heat from the thermal source to the surroundings.There are lots of advantages and significances if wood-based thermal conductive composite is applied to the indoor decorations field like the wooden heating floor and wood products.Not only the advantages of natural renewable wood resources such as low density,easy processing and cost-effectiveness could be exploited to the full,but also non-renewable resources are reduced.Moreover,it is important to achieve the improved efficiency and high-value utilization of wood resources.Indeed,the thermal conductivity of wood is low which is affected by moisture content,porous structure and chemical composition and its heat transfer is anisotropic.Owing to the enhancement of heat transfer medium,decrease of the interface thermal resistance,and strengthening of the surface heat transfer layer,the heat transfer property of wood-based thermal conductive composites is improved.There are three preparation technologies which are impregnation treatment,recombination and compounding,and surface treatment.Commonly,wood veneers are firstly carbonized to form a complete thermal conductive carbon skeleton and then immersed into the polymer or thermal conductive resin.Moreover,microwave puffed treatment can form three-dimensional network cracks in the wood,increasing the filling space of the thermal conductive units especially low melting points alloy.Recombination and compounding is to add a certain proportion of thermal conductive units and adhesives into wood units such as wood veneer,shavings,fibers and flours,etc.,then hot pressing or melt extrusion into wood-based boards.The surface treatment gives the wooden substrate a thermally conductive layer.When depositing metal on the wood surface by the method of electroless plating,the heat transfer property of the wooden substrate improved on account of the thermal conductivity of free electrons in the metal is stronger than that of the phonons in wood.Similarly,surface finishing thermal conductive coatings can make the heat transfer performance of the wooden substrate better.At present,the research of wood thermal conductive composite stays at the laboratory research stage and has not yet formed industrialized production or applications.The improvement effect and the optimal proportion of thermal conductive units,and the balance between the thermal conductivity and mechanical properties are current research focus.In the future,the optimization of the preparation method,the construction of the heat transfer prediction model,the enhancement of interface combination,and the expansion of multiple functions will be the next research direction.In conclusion,the effect factors and the theoretical calculation formula of the thermal conductivity of wooden materials are outlined,the heat transfer enhancement mechanisms and preparation technologies of wood-based thermal conductive composites are summarized,and the future research direction and application fields are prospected.