CNT基木塑复合材料的力学性能、电磁屏蔽性能

采用碳纤维(CF)和碳纳米管(CNT)通过模压工艺制备出具有电磁屏蔽功能的丙烯酸酯木塑复合材料。借助材料试验机、动态热机械分析仪、微欧计和电磁屏蔽测量仪等详细研究CNT质量分数对丙烯酸酯木塑复合材料弯曲性能、动态力学性能、电阻率和电磁屏蔽效能的影响。结果表明,添加质量分数为2%的CNT,使得复合材料的弯曲强度和弯曲弹性模量分别增加了10%和16%。复合材料的储能模量也在CNT质量分数为2%时达到最大值,之后储能模量随着CNT的增加而逐渐下降,损耗因子在CNT质量分数多于2%时也逐渐增加。复合材料的吸水率和导电性能随着CNT含量的增加而增加。同时复合材料的电磁屏蔽效能也随着CNT含量增加而递增。在30~1 500 MHz范围内,电磁屏蔽效能从27 d B增加到40 d B。结果证明,当CNT质量分数在2%时,丙烯酸酯木塑复合材料具有较佳的力学性能和较好的电磁屏蔽效能(30 d B),能满足商业要求。

Mechanical and Electromagnetic Interference Shielding Effectiveness of CNT Based Wood Plastics Composites

Based on carbon fiber (CF) and carbon nanotubes (CNT),the acrylate wood plastics composites (WPC) with electromagnetic interference (EMI) shielding function were prepared using a compressing method. The influences of CNT on the flexural properties,dynamical mechanical properties, electrical resistivity and EMI properties were studied using a material testing machine,dynamical mechanical analyzer,micro-ohmmeter and EMI apparatus. The results show that adding 2% CNT can increase flexural strength and flexural modulus by 10% and 16%,respectively. Also,the storage modulus of composite reaches the maximum value at 2% CNT,and then it decreases as CNT content increases. And the improvement in loss factor at above 2% CNT indicates lagging becomes serious. The water absorption and conductivity of composite increase as CNT content increases. At the same time,EMI property of composites increases with increasing CNT content,and it increases from 27 dB to 40 dB in the range of 30-1500 MHz. It can be concluded that acrylate WPC owns better mechanical and EMI properties at 2% CNT,which can meet the requirements of commerce.