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应用两相模型探讨多壁碳纳米管(MWCNTs)填充聚苯乙烯(PS)复合体系的动态流变特性.结果表明,体系线性黏弹行为与PS本体的应变放大效应及MWCNTs填料相的弛豫密切相关.在不同温度下,应变放大因子(Af)随MWCNTs体积分数(φ)的变化规律符合扩散控制的粒子串聚集(CCA)模型.φ<0.020时,MWCNTs分散较均匀,温度变化对Af-φ关系无显著影响.φ较高时,MWCNTs形成聚集体,Af随温度升高而显著降低.填料相特征动态模量(G′f1与G″f0)随温度的变化符合Arrhenius关系,且活化能(E′a与E″a)在φ=0.025附近发生不连续变化,说明温度对均匀分散的MWCNTs(φ<0.020)与MWCNTs逾渗网络(φ>0.025)的黏弹行为具有不同的影响规律.复合体系黏弹逾渗现象与导电逾渗密切相关,导电逾渗转变上限浓度范围为φ=0.020～0.025.
The dynamic rheological properties of multi-walled carbon nanotubes (MWCNTs) filled polystyrene (PS) composite system were investigated by using two-phase model.The results show that the strain-amplifying effect of linear viscoelastic behavior and PS bulk and the relaxation of filler phase , The variation of strain amplification factor (Af) with MWCNTs volume fraction (φ) accords with diffusion-controlled particle string aggregation (CCA) model at different temperatures.When φ <0.020, MWCNTs dispersed more evenly, -φ, the formation of aggregates of MWCNTs and the decrease of Af with the increase of temperature, the Arrhenius relationship with the change of the dynamic modulus of filler phase (G’f1 and G “f0) The activation energies (E’a and E ”a) discontinuously change around φ = 0.025, indicating that the viscoelastic behavior of MWCNTs (φ <0.020) and MWCNTs percolation networks (φ> 0.025) Influence law.The viscoelastic percolation phenomenon of the composite system is closely related to the conductive percolation, and the upper limit of conductive percolation transition range is φ = 0.020-0.025.