聚苯胺/蒙脱土电流变液的稳定性

TEMPERATURE EFFECT AND ANTISEDIMENTATION OF POLYANILINE/MONTMORILLONITE ELECTRORHEOLOGICAL FLUID

采用乳液共混插层法制备了高介电常数的聚苯胺/蒙脱土纳米复合材料微粒.聚苯胺/蒙脱土电流变液在外电场下的剪切强度达8.26 kPa(3 kV/mm DC,5 s-1),并具有较好的温度稳定性,其剪切应力在10～100℃内随温度变化仅为6.5％(1.5 kV/mm,DC,1.61 s-1),静置60天沉降率仅为1％.IR及XRD分析表明,聚苯胺插入到蒙脱土层间,形成纳米复合颗粒, TEM标示颗粒的粒径约为100 nm.在1000 Hz,20℃时,聚苯胺/蒙脱土颗粒的介电常数比纯蒙脱土提高2.7倍,比纯聚苯胺提高5.5倍,电导率增加8.5倍.

Polyaniline-montmorillonite nanocomposite particles were synthesized by using an emulsion intercalation method and were characterized by IR, XRD and TEM spectrometry. The diameter of MMT-PANI particles is about 100 nm. The antisedimentation of PANI-MMT nanocomposite particles is excellent, and the sedimentation ratio of PANI-MMT ERF after 60 days was about 99%. In the range of 10~100 ℃, the shear stress changed slightly (about 6.5%) with the increase of temperature. The electrorheological behavior of the suspensions of PANI-MMT nanocomposite particles in silicone with a 30% mass fraction was investigated under DC electric fields. It was found that the mechanical performance of MMT-PANI ER fluids displays a notable ER effect under DC current field. The shear stress is 8.26 kPa (3 kV/mm, DC, 5 s-1), and much higher than that of pure polyaniline (PANI), montmorillonite (MMT) and mixture of polyaniline with clay (MMT+PANI).The dielectric constant of PANI-MMT nanocomposite increased 2.7 times than MMT and 5.5 times than PANI (1000 Hz, 20 ℃). In the meanwhile, the electric conductivity of PANI-MMT particles increased 8.5 times. The relevantinfluential factors between shear stress and electric fields, between shear stress and temperature were discussed preliminarily.