碳纖維補強複合材料電氣性質與拉伸性質之研究

A Study on the Electrical and Tensile Properties of Carbon Fiber Reinforced Composites

林聖智(S. Z. Lin)

指導教授 ： 鄭國彬 ； 鄧道興

國立臺北科技大學/工程學院/有機高分子研究所/碩士(2005年)

摘要

由於市售之高分子材料並未具有導電與電磁波屏蔽效益功能。有鑑於此，本文將發展一導電性複合材料，以針對電磁波屏蔽效益之應用材料。故本文係使用高分子混摻法將碳纖維依照不同之含量添加到不同之高分子基材(PP、TPR、PP/TPR)內，經由雙螺桿捏合機，將碳纖維均勻混煉在不同之高分子基材內，經射出成型機製成導電性複合材料，以探討其體積電阻係數、電磁波屏蔽效益等電氣性質及拉伸性質及其破損行為。
本實驗採用向量網路分析儀(Vector Network Analyzer)搭配同軸夾具以評估電磁波遮蔽值，所規範的電磁波量測頻率範圍設定在50MHz-3GHz，經測試結果顯示PP/CF、TPR/CF及PP/TPR/CF導電性複合材料在厚度為20mm時，頻率為144~3000MHz下之電磁吸收損失均可達40~60dB。拉伸測試方面，添加碳纖維對PP具有補強效果，其最大拉伸強度可達47MPa，較純PP之最大拉伸強度可提升約47.56%。而對TPR與PP/TPR則是呈現下降之現象。較純TPR與PP/TPR之最大拉伸強度約下降約30.67%與20.55%。
本文經過SPSS PC+統計分析軟體之逐步回歸分析法求得其數學模型，並以此數學模型可推論在不同厚度、入射頻率、碳纖維重量百分比等之EMSE效果。更進一步利用MATHMATICA 數學軟體繪製3D趨勢圖，以分析比較在各種不同成分、不同厚度、入射頻率、碳纖維重量百分比等之導電性複合材料EMSE之效應。預期其導電性複合材料可以適用於電子或電機儀器之機殼、手機外殼、通訊零件之機殼及潔淨室內之抗靜電襯墊等之應用。

關鍵字

聚丙烯 ； 熱塑性橡膠 ； 碳纖維 ； 導電性複合材料 ； 體積電阻係數 ； 電磁波屏蔽效益

並列摘要

Common polymers are not conductive nor do they have any electromagnetic shielding function. In view of this, this research proposed to develop conductive composites with electromagnetic shielding effectiveness. The polymer blend method was used in this study. Carbon fibers of various quantities were added into different polymer matrices (PP, TPR, PP/TPR), then they were well blended by a twin-screw mixer and finally injection molding was applied to produce Conductive composites. In addition to the electrical properties that included Volume Resistivity and electromagnetic shielding effectiveness, the tensile properties as well as their damage behaviors were investigated.
The electromagnetic shielding values were measured by a Vector Network Analyzer with coaxial holder, which is capable of measuring incident frequency ranges between 50MHz and 3GHz. The experimental results showed that for the 20mm thick specimens measured within a frequency range from 144 MHz to 3000MHz, their electromagnetic shielding effectiveness was 40~60dB for either PP/CF, TPR/CF or PP/TPR/CF conductive composites. For the tensile testing, the results showed that the maximum tensile strength of CF/PP conductive composite was 47MPa which was improved by about 47.56% compared to that of pure PP. Nevertheless, it was found that the maximum tensile strength dropped for both CF/TPR and CF/PP/TPR conductive composites. The figures were dropped respectively 30.67% for CF/TPR compared to pure TPR and 20.55% for CF/PP/TPR compared to pure PP/TPR.
This study obtained a mathematical model through the stepwise regression analysis of the SPSS PC+ statistical package. The electromagnetic shielding effectiveness (EMSE) would be inferable by key-in factors as composite thickness, incident frequency and weight percentage of carbon fiber. Furthermore, the MATHMATICA software was applied to draw 3D trend pictures, which was able to analyze and predict the EMSE of conductive composites with different composition, thickness, incident frequency or weight percentage of carbon fiber. It is expected that conductive composites could be useful in applications such as the casing of electronic and electrical machinery or apparatus communication apparatus, and mobile phones, antieletrostatic mat in cleaning room, etc.

並列關鍵字

Polypropylene (PP) ； Thermoplastic Rubber (TPR) ； Carbon Fiber (CF) ； Conductive Composites ； Volume Resistivity ； Electromagnetic Shielding Effectiveness

參考文獻

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