The study on the correlation between electrical percolation and viscoelastic percolation for carbon black（CB） filled high-density polyethylene（HDPE） conductive composites was carried out through examining the fill...The study on the correlation between electrical percolation and viscoelastic percolation for carbon black（CB） filled high-density polyethylene（HDPE） conductive composites was carried out through examining the filler volume fraction dependence of the volume resistivity（ρ） and normalized dynamic storage modulus,G c/G p,in which G c,G p are dynamic storage modulus of the composites and the matrix respectively. The results revealed that the critical filler volume fraction of viscoelastic percolation approached the lower threshold（φ1） of the electrical percolation,indicating an insulator-semiconductor change corresponding to the beginning of network structure formation. Substituting K for A,a modified Kerner-Nielson equation was obtained and used to analyze the formation of network structure. It is suggested that parameter K is associated with CB volume fraction. [WT5HZ]展开更多
The influence of temperature and mass fraction of Pluonic F127 on the rheological properties of polyvinyl butyric （PVB）/Pluronic F127/polyethylene glycol （PEG） 200 blend systems was investigated by a rotational rh...The influence of temperature and mass fraction of Pluonic F127 on the rheological properties of polyvinyl butyric （PVB）/Pluronic F127/polyethylene glycol （PEG） 200 blend systems was investigated by a rotational rheometer with parallel plates. The results show that the blend systems approach homogeneous state at 140, 150 and 160℃while the rheological properties of the blend systems significantly deviate from the homogeneous systems at 120℃. Shear thinning behavior is observed for all the blend systems at different temperatures and is enhanced by increasing Pluronic F127 content. The complex viscosity, storage modulus, loss modulus, zero-shear activation energy and flow recovery of the blend systems increase with the increase of Pluronic F127 content. There is a crossing point for the loss modulus and the storage modulus of each sample at high frequency, which is called specified frequency （SF）. The loss modulus is larger than the storage modulus when the frequency is less than the SF, and when frequency is more than SF, the loss modulus is smaller than the storage modulus.展开更多
文摘The study on the correlation between electrical percolation and viscoelastic percolation for carbon black（CB） filled high-density polyethylene（HDPE） conductive composites was carried out through examining the filler volume fraction dependence of the volume resistivity（ρ） and normalized dynamic storage modulus,G c/G p,in which G c,G p are dynamic storage modulus of the composites and the matrix respectively. The results revealed that the critical filler volume fraction of viscoelastic percolation approached the lower threshold（φ1） of the electrical percolation,indicating an insulator-semiconductor change corresponding to the beginning of network structure formation. Substituting K for A,a modified Kerner-Nielson equation was obtained and used to analyze the formation of network structure. It is suggested that parameter K is associated with CB volume fraction. [WT5HZ]
基金Project(20776161) supported by the National Natural Science Foundation of China
文摘The influence of temperature and mass fraction of Pluonic F127 on the rheological properties of polyvinyl butyric （PVB）/Pluronic F127/polyethylene glycol （PEG） 200 blend systems was investigated by a rotational rheometer with parallel plates. The results show that the blend systems approach homogeneous state at 140, 150 and 160℃while the rheological properties of the blend systems significantly deviate from the homogeneous systems at 120℃. Shear thinning behavior is observed for all the blend systems at different temperatures and is enhanced by increasing Pluronic F127 content. The complex viscosity, storage modulus, loss modulus, zero-shear activation energy and flow recovery of the blend systems increase with the increase of Pluronic F127 content. There is a crossing point for the loss modulus and the storage modulus of each sample at high frequency, which is called specified frequency （SF）. The loss modulus is larger than the storage modulus when the frequency is less than the SF, and when frequency is more than SF, the loss modulus is smaller than the storage modulus.
