成型加工工艺条件对蒙脱土在聚丙烯基体中分散的影响

Study of the controllable dispersion of polypropylene/montmorillonite nanocomposites

利用自制的微纳层叠挤出成型设备在不同螺杆转速工艺条件下制备了聚丙烯(PP)/蒙脱土(MMT)纳米复合材料。通过电子扫描显微镜(SEM)、广角X射线衍射(WAXD)、透射电子显微镜(TEM)和万能拉伸试验机对不同螺杆转速下的试样进行了结构与性能的测试与分析。结果表明,改变成型工艺条件中的螺杆转速会影响MMT在PP基体中的分散和力学性能,但是作用效果不明显;适当提高螺杆转速在一定程度上可提高MMT层间距,但过高的螺杆转速反而会造成MMT层间距变小。

Polypropylene/montmorillonite （PP/MMT） nanocomposite samples have been prepared under different processing conditions of alternating screw rotation using a self-made micro-nano extrusion device. The effects of screw rotation on the dispersion of MMT, the structure and the mechanical properties were characterized by scan- ning electron microscopy （SEM）, wide angle X-ray diffraction （WAXD）, transmission electron microscopy （TEM） and tensile tests. The results showed that the screw rotation did not have a significant effect on the expan- sion of the interlayer spacing of MMT, although the interlayer spacing of MMT increased as the screw rotation increased up to a certain extent, while smaller interlayer spacings could be obtained for higher screw rotations. The MMT interlayer spacing and the dispersion of MMT both have an influence on the mechanical properties of the nano- composite materials.