聚乳酸/蒙脱土纳米复合材料的流变行为  

Rheological Behavior of Polylactide/Montmorillonite Nanoeomposites

作　　者：吴亮[1] 吴德峰[1] 张明[1] 吴兰峰[1] 

机构地区：[1]扬州大学化学化工学院,江苏扬州225002

出　　处：《中国塑料》2006年第11期53-57,共5页China Plastics

基　　金：江苏省物理化学重点学科开放基金

摘　　要：采用熔融插层法制备了插层型的聚乳酸/蒙脱土纳米复合材料,利用旋转流变仪对其流变行为进行了研究。稳态预剪切和大振幅振荡剪切实验结果表明,蒙脱土晶粒逾渗网络结构具有剪切敏感性,但稳态预剪切更容易破坏蒙脱土晶粒的逾渗结构；反向流和起始流实验结果表明,剪切破坏的逾渗网络在静态退火过程中可以重建,而应力过冲现象的出现则是网络重建的标志；不同剪切速率下应力过冲的最大值都出现在2%应变处,这种应力与应变之间的标度关系表明蒙脱土晶粒类液晶态的形成可能是网络重建的驱动力。Polylactide/montmorillonite nanocomposites （PLA/MMT） were prepared via melt intercalation. The rheological behavior of PLA/MMT was characterized using plate rheometer. The results from steady preshear and large amplitude oscillatory shear （LAOS） measurements showed that the percolated clay tactoids network structure was very sensitive to the shear deformation. Compared with that of LAOS, the steady preshear could destroy percolation network more easily. The results from transient shear measurements such as flow reverse and start-up flow showed that the ruptured network structure could reorganize, which was indicated by the appearance of stress overshoot during quiescent annealing process. The maximum of stress overshoots all appeared around a strain of 2 0,6 independent of shear rates, suggesting that the reorganization of percolation network be driven by the formation of liquid crystalline-like structure due to the long range interactions among the clay tactoids.

关 键 词：聚乳酸 蒙脱土 纳米复合材料 流变 

分 类 号：TB383.1[一般工业技术—材料科学与工程]