PB/nano-SiO_2复合材料的流变性能

Rheological Behaviors of PB/nano-SiO_2 Composites

采用熔融共混法制备了聚丁烯(PB)/nano-SiO2复合材料,并用毛细管流变仪研究了PB及其复合材料在较宽剪切速率(1×102～6×103 s-1)的流变行为。讨论了nano-SiO2含量、剪切应力、剪切速率及温度对熔体流变性、非牛顿指数和黏流活化能的影响。结果表明:PB及其复合材料的非牛顿指数均小于1,但PB/nano-SiO2的非牛顿指数大于PB的;随nano-SiO2含量增加,PB/nano-SiO2复合材料非牛顿指数上升;PB/nano-SiO2复合材料的熔融流动性随nano-SiO2用量的增加而下降;相同剪切速率时,PB/nano-SiO2的黏流活化能大于PB的。

The rheological behavior of PB/nano-SiO2 composites prepared by melt blending was studied in a wide shear rate （1×10^2～6×10^3^-1） using capillary rheome-ter. The effect of nano-SiO2 content, shear stress, shear rate and temperature on the meltrheology, non-Newtonian index and viscous flow activation energy was discussed. The results show that non-Newtonian index of PB and PB/SiO2 composites are less than 1, but non-Newtonian index of PB/nano-SiO2 is higher than that of PB. With the increase of nano-SiO2 content, non-Newtonian index of the composites increases. The melt flow behavior of PB/nano-SiO2 composites reduces with the increase of the content of nano-SiO2. At the same rate, viscous flow activation energy of Pg/nano-SiO2is grea-ter than that of PB.