摘要
分别制备了炭黑、碳纳米管、炭黑/碳纳米管简单共混以及炭黑碳纳米管化学键合聚丙烯复合材料,研究了不同体系的导热、导电和流变性能。研究发现,使用炭黑/碳纳米管简单共混或化学键合掺杂的复合材料热导率分别达到0.60W/mk和0.63 W/mk,而使用炭黑或碳纳米管杂化的组分热导率仅仅为0.36 W/mk和0.45 W/mk。掺杂碳纳米管或炭黑/碳纳米管简单共混填料的复合材料体积电阻下降了6个数量级,而掺杂炭黑或炭黑/碳纳米管化学键合填料的复合材料均有较好的绝缘性。掺杂杂化组分后,复合材料均出现了剪切变稀现象,在储能模量与频率曲线上低频区出现"第二平台",但掺杂炭黑/碳纳米管化学键合样品的第二平台极微弱。微观结构发现填料在基体中分散良好,填料间形成了很好的架桥。研究结果表明,简单使用炭黑、碳纳米管掺杂对复合材料的热导率改善不佳,使用炭黑/碳纳米管简单混合虽能大幅提高热导率,但影响复合材料的绝缘性能,而将炭黑/碳纳米管化学键合后可满足制备导热绝缘复合材料的要求。
Polypropylene thermal conductive composites with different hybrid fillers were prepared,and the thermal conductivity,electrical conductivity and rheological properties were tested. The results show that the thermal conductivity is improved by adding hybrid parts. By adding 10% of carbon black and carbon nanotube simple mixture and chemical bonded filler to PP/Al2O3 composite,the thermal conductivity is improved to 0. 60 W/mk and 0. 63 W/mk,respectively. Using pure carbon black and pure carbon nanotubes as hybrid parts,the thermal conductivity is only 0. 36 W/mk and 0. 45 W/mk. The volume resistance declines 106 order of magnitude for the composite using carbon nanotube and the simple mixture,whereas the composite filled with pure carbon black or chemical bonded fillers show insulation behavior. An obvious shear thinning phenomenon appears in η*vs. ω curves after adding hybrid parts. A second plateau at low frequency region is observed,but it is very weak for the chemical bonded filler modified composites. For this composite,the microstructure shows that the filler distributes well in the matrix and connecting bridges are formed between the fillers. The results show that the thermal conductivity cannot be improved pronouncedly by pure carbon black or pure carbon nanotube. The simple mixture of carbon black and carbon nanotube can induce better thermal conductivity,but it will also lead to some electrical conductivity. The application of chemical bonded carbon black and carbon nanotube can meet the demand of thermally conductive and insulated composites.
出处
《高分子材料科学与工程》
EI
CAS
CSCD
北大核心
2015年第4期92-95,101,共5页
Polymer Materials Science & Engineering
关键词
碳纳米管
炭黑
聚丙烯
热导率
流变行为
carbon nanotubes
carbon black
polypropylene
thermal conductivity
rheological behavior
