微型注塑制备碳纳米管硅橡胶导电复合医用材料

Preparation of Electrical Conductive Silicone Rubber/Carbon Nanotubes Composites for Applications in Biomedicine by Microinjection

柔性导电材料是制备一些尖端医疗电子器件的重要材料。文中采用高速机械搅拌、超声波分散、球磨工艺制备了综合性能优异的碳纳米管液体橡胶纳米复合材料,碳管分散均匀,导电率最高可达25S/m,柔韧性保持不变。医疗电子器件具有微型化高精度的特点,需采用微加工成型技术,文中研究了液体橡胶柔性导电材料的微注射成型技术,考察了微加工条件对材料的导电性能的影响。结果显示,注射压力和模具温度越高,材料的导电率越低,其他加工条件则对材料导电性能影响不大。在拉伸的循环实验中导电率随应变呈指数变化。

The flexible electric conductive material is very important for preparation of some sophisticated electronic medical devices. In this paper, a kind of electrical conductive liquid silicone rubber （LSR） / carbon nanotubes （CNTs） nanocomposite with excellent comprehensive performance was prepared. High rate mechanic stir, ultrasonic irradiation and ball mill were used as dispersion methods of CNTs in LSR. The results show that CNTs are evenly distributed in LSR, the electrical conductivity of the composite can reach 25 S/m, and the flexibility is as well as pure LSR. Some medical electronic devices have characteristics of minuteness and high precision, are required to develop the micro injection molding technology. The microinjection was used to processing LSR/CNTs nanocomposites, and the effect of microinjection parameters on the electrical conductivity of the nanocomposites was studied. It is found that increasing injection pressure and mold temperature will decrease the electrical conductivity of the nanocomposites, however, the other processing parameters almost don＇t affect the electrical conductivity of composites. Electrical conductivity of the composite during stretching cycle is recorded, and the conductivity varies exponentially with tensile rate.