强制组装法制备碳系导热复合材料的研究

发布时间：2018-06-19 16:58

本文选题：强制组装 + 导热网络　；参考：《北京化工大学》2017年硕士论文

【摘要】：为了制备高导热性能的复合材料,本文改变常用共混成型方法,提出强制组装法,通过空间限域增强强制组装程度,本文用强制组装法制备了单填料填充紫外胶(UV)、单填料填充聚二甲基硅氧烷(PDMS)、二元填料填充PDMS三种类型复合材料。首先,介绍了强制组装法的原理,研究填料含量和强制组装程度对碳纤维/UV复合材料导热性能的影响,并通过电镜(SEM)对复合材料断面碳纤维的分布进行观察。其次,用强制组装法制备了碳纤维/PDMS复合材料,研究填料含量对导热性能的影响,并重点研究强制组装程度对垂直和水平导热性能的影响,用SEM对复合材料断面进行观察,观察填料在基体中的分布。最后,用强制组装法制备二元填料填充PDMS,研究二元填料的种类、含量对复合材料导热性能的影响,重点研究了强制组装程度对二元填料复合材料垂直和水平导热性能的影响,并用SEM对其断面进行观察。结果表明:1.强制组装法制备单填料填充UV复合材料,其导热性能随着填料含量和强制组装程度的增加而增加。强制组装程度相同,碳纤维含量由4wt%增加到8wt%,垂直和水平导热率分别提高24.49%和77.45%;碳纤维含量相同,强制组装程度提高,垂直和水平导热率分别提高25.42%和129.63%,SEM对断面观察发现填料含量增加使填料更加紧密,强制组装使碳纤维导热网络更加完善。2.强制组装法制备单填料填充PDMS复合材料,其导热性能随着填料含量和强制组装程度的增加而增加。强制组装程度对导热性能的提高有非常大的影响,相对提高填料含量,强制组装更能有效提高导热性能。强制组装程度相同,750μm时,含量由10wt%增加到23wt%后,垂直和水平导热率分别提高228%、235.42%;碳纤维含量为23wt%,强制组装程度提高,厚度由750 μm缩小到150 μm,垂直和水平导热率分别提高164.52%、316.15%。3.强制组装法制备二元填料填充PDMS复合材料,其导热性能随着填料含量和强制组装程度的增加而增加。1Owt%碳纤维与石墨烯填充,强制组装程度提高后垂直和水平导热率分别提高151.72%、175.21%; 10wt%碳纤维与碳纳米管填充,强制组装程度增加垂直和水平导热率分别提高150%、480.29%; 15wt%碳纤维与石墨烯填充基体,强制组装程度增加,直和水平导热率分别提高131.43%、491.59%; 15wt%碳纤维与碳纳米管填充基体,强制组装程度提高后垂直和水平导热率分别提高137.84%、662.74%。4.总结以上结论,强制组装法与增加填料含量两种提高导热性能的方法相比,强制组装法对导热率提高幅度更大,并且对水平方向导热率的提高可达数倍,验证了强制组装原理的有效性。强制组装法制备了导热性能良好的导热复合材料,碳纤维填充含量为23wt%,水平导热率达到13.40W.(m·K)-1,对二元填料复合材料,15wt%碳纤维与4wt%碳纳米管混合水平导热率达到11.6W·(m·K)-1。
[Abstract]:In order to prepare the composite materials with high thermal conductivity, this paper changes the common blending molding method, puts forward the forced assembly method, and enhances the compulsory assembly by spatial restriction. In this paper, a single filler filled UV adhesive (UV), a single filler filled with poly two methylsiloxane (PDMS), and three kinds of PDMS composites filled with two element filler are prepared by forced assembly method. First, the principle of forced assembly method was introduced, and the effect of filler content and forced assembly degree on the thermal conductivity of carbon fiber /UV composites was investigated. The distribution of carbon fiber in the composite section was observed by electron microscope (SEM). Secondly, carbon fiber /PDMS composite was prepared by forced assembly method, and the thermal conductivity of the filler was studied. The influence of the forced assembly degree on the vertical and horizontal thermal conductivity was studied, and the distribution of the filler in the matrix was observed with SEM. Finally, the two element filler was filled with the forced assembly method to fill the PDMS. The influence of the two element packing and the content of the material on the thermal conductivity of the composite was studied. The effect of the degree of assembly on the vertical and horizontal thermal conductivity of the two element filler composite was observed and observed with SEM. The results showed that the 1. forced assembly method was used to prepare the single filler to fill the UV composite. The thermal conductivity of the composite was added with the increase of the filler content and the compulsory assembly degree. Increasing to 8wt%, the vertical and horizontal thermal conductivity increased by 24.49% and 77.45%, respectively, the content of carbon fiber was the same, the degree of forced assembly was increased, and the vertical and horizontal thermal conductivity increased by 25.42% and 129.63% respectively. SEM was found to increase the filler content to make the packing more compact, and the forced assembly made the carbon fiber heat conduction network more perfect.2. compulsory assembly method. The thermal conductivity of PDMS composites filled with single filler is increased with the increase of filler content and the degree of forced assembly. The degree of forced assembly has a great effect on the increase of thermal conductivity. Relative increase of filler content, forced assembly can improve the thermal conductivity more effectively. The content of forced assembly is the same, the content increases from 10wt% to 2 when 750 mu. After 3wt%, the vertical and horizontal thermal conductivity increased by 228%, 235.42%, the carbon fiber content was 23wt%, the forced assembly degree was increased, the thickness was reduced from 750 mu m to 150 m, and the vertical and horizontal thermal conductivity increased by 164.52% respectively. The 316.15%.3. forced assembly method was used to prepare two element filler filled PDMS composite. The thermal conductivity of the composite was with the filler content and forced assembly. Increasing the degree of.1Owt% carbon fiber and graphene filling, the vertical and horizontal thermal conductivity increased by 151.72%, 175.21%; 10wt% carbon fiber and carbon nanotubes were filled, and the vertical and horizontal thermal conductivity increased by 150%, 480.29% respectively. 15wt% carbon fiber and graphene filled matrix, forced assembly The degree of direct and horizontal thermal conductivity increased by 131.43%, 491.59% respectively. 15wt% carbon fibers and carbon nanotubes filled the matrix, and the vertical and horizontal thermal conductivity increased by 137.84% after the forced assembly level increased. 662.74%.4. summarized the above conclusion. Forced assembly method was compared with two methods of increasing the filler content to improve the thermal conductivity. The increase of thermal conductivity is greater, and the increase of the thermal conductivity of the horizontal direction is several times. The validity of the forced assembly principle is verified. The forced assembly method has prepared the thermal conductive composite with good thermal conductivity, the content of carbon fiber filling is 23wt%, the horizontal thermal conductivity reaches 13.40W. (m. K) -1, and the composite material of two yuan filler, 15wt% carbon fiber and 4wt The horizontal thermal conductivity of% carbon nanotubes is 11.6W (M. K) -1..
【学位授予单位】：北京化工大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB332

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