填充型导热聚芳醚腈复合材料的制备及性能研究

发布时间：2018-02-11 20:42

本文关键词： 聚芳醚腈复合材料表面改性导热性能力学性能　出处：《电子科技大学》2015年硕士论文　论文类型：学位论文

【摘要】：聚芳醚腈[poly(arylene ether nitriles),PEN],作为一类综合性能优异的芳香杂环高分子聚合物,具有优良的耐热性、绝缘性、耐化学腐蚀及机械性能等,自其上世纪80年代初发明以来就受到广泛关注。本实验室通过分子设计合成了一系列聚芳醚腈树脂,并以此为基础开展了结构与性能、功能的研究,而有关聚芳醚腈的导热性能却少有研究。本文以端基交联型聚芳醚腈(PEN-t-ph)作为基体,分别以改性Al2O3、石墨、碳纳米管为导热填料,通过溶液共混将填料填充到PEN-t-ph聚合物基体中。为了促进填料-基体两相的界面相容性,我们首先对无机填料进行了表面改性,并采用扫描电子显微镜(SEM)、热失重分析仪(TGA)、傅立叶变换红外光谱仪(FTIR)、紫外吸收光谱分析仪(UV-Vis)以及X射线衍射仪(XRD)等仪器研究表征了改性填料表面形貌和结构。最后利用连续超声技术和溶液流延方法制备了导热PEN-t-ph聚合物基复合材料,并分别研究了填料含量、填料改性、热处理对复合材料的导热性能、力学性能以及热稳定性等的影响。采用高导热系数的无机填料填充聚合物材料可以明显提高材料的导热性能。实验结果表明,随着改性Al2O3填料含量的增加,PEN-t-ph聚合物基复合材料的热导率逐渐升高;将不同粒径微米-纳米混杂Al2O3按一定比例填充到PEN-t-ph树脂中时,复合材料表现出比填充单一Al2O3更优异的导热性能。用改性石墨填充PEN-t-ph,同样也能改善PEN-t-ph材料的导热性能,当石墨的质量分数为16wt%时,复合材料的热导率是纯树脂的1.8倍;而且石墨经过表面改性后,复合体系的导热系数增加更加显著。随着导热MWCNT-boehmite填料添加量的增加,改性PEN-t-ph复合材料的的热导率初始变化缓慢;当填料含量达到一定临界值时,材料的热导率迅速增长。当MWCNT-boehmite的填充量达到15wt%时,复合材料的导热系数是0.881 W/mK,约是纯树脂的2.7倍。伴随复合材料热导率上升的同时,材料的力学性能不可避免的受填料含量的影响。当填料含量较低时,PEN-t-ph复合材料的力学性能随着填料含量的增加而增加;继续增加填料的含量,材料的力学性能又开始下降。无机填料的填充对复合材料的热稳定性影响很小,样品初始分解温度(Tid)和最大分解温度(Tmax)范围分别在490oC和520oC左右,材料保持了优异的热性能;此外复合材料的玻璃化转变温度(Tg)都在170oC以上。
[Abstract]:As a class of aromatic heterocyclic polymers with excellent comprehensive properties, poly(arylene ether nitriles-pen has excellent heat resistance, insulation, chemical corrosion resistance and mechanical properties. A series of poly (aryl ether nitrile) resins were synthesized by molecular design in our laboratory, and the structure, properties and functions of the resins were studied. However, the thermal conductivity of poly (aryl ether nitrile) was seldom studied. In this paper, the end group crosslinked polyether nitrile (PEN-t-ph) was used as the matrix, and the modified Al _ 2O _ 3, graphite and carbon nanotubes were used as thermal conductors, respectively. The filler was filled into the PEN-t-ph polymer matrix by solution blending. In order to promote the interfacial compatibility between the filler and the matrix, the inorganic filler was first modified. The surface morphology and structure of the modified fillers were characterized by scanning electron microscopy (SEM), thermogravimetric analyzer (TGA), Fourier transform infrared spectroscopy (FTIR), UV absorption spectrometer (UV-Vis) and X-ray diffractometer (XRD). The thermal conductive PEN-t-ph polymer matrix composites were prepared by continuous ultrasonic technique and solution flow casting method. The effects of filler content, filler modification and heat treatment on the thermal conductivity of composites were studied. The influence of mechanical properties and thermal stability. The thermal conductivity of polymer filled with inorganic fillers with high thermal conductivity can be improved obviously. The thermal conductivity of PEN-t-ph polymer matrix composites increased with the increase of the filler content of modified Al2O3, and when different particle size micron-nanometer hybrid Al2O3 was filled into PEN-t-ph resin in a certain proportion, The thermal conductivity of the composite is better than that of single Al2O3. The thermal conductivity of the composite filled with modified graphite can also improve the thermal conductivity of PEN-t-ph. When the mass fraction of graphite is 16 wt%, the thermal conductivity of the composite is 1.8 times that of pure resin. After surface modification, the thermal conductivity of the composite system increased more significantly, and the initial change of thermal conductivity of the modified PEN-t-ph composites was slow with the increase of the content of thermal conductive MWCNT-boehmite fillers, and when the filler content reached a certain critical value, the thermal conductivity of the modified PEN-t-ph composites changed slowly when the filler content reached a certain critical value. The thermal conductivity of the composites increases rapidly. When the MWCNT-boehmite content reaches 15 wt%, the thermal conductivity of the composites is 0.881 W / mK, about 2.7 times that of the pure resin, and the thermal conductivity of the composites increases with the increase of the thermal conductivity of the composites. When the filler content is low, the mechanical properties of PEN-t-ph composites increase with the increase of filler content. The mechanical properties of the composites began to decline again. The thermal stability of the composites was slightly affected by the filling of inorganic fillers. The initial decomposition temperature (Tid) and the maximum decomposition temperature (Tmax) of the samples were about 490 OC and 520 OC, respectively, and the thermal properties of the composites were excellent. In addition, the glass transition temperature (TG) of the composites is above 170 OC.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33

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