振动共混对PC/PP多重结晶行为的影响

在传统转矩流变仪上叠加机械振动帛成了振动共混流变仪，叠加机械振动的流动影响共混物的相形态，因此影响了PC／PP的多重结晶行为。DSC和偏光显微联用分析发现，所有峰对应的结晶都是异相成核，共混频率或振幅增高，减小分散相相畴尺寸，PP粒子的异相核会向PC迁移，所以制备的共混物的低温结晶峰越强，而高温结晶峰减弱，共混振幅很大时，中等尺寸粒子界面附生非均相成核等效增加了较高温度成核率，结晶温度较高。

EFFECTS OF VIBRATION MIXING ON THE MULTIPLE CRYSTALLIZATION OF PC/PP BLENDS

A novel vibration internal mixer was made from the conventional internal mixer through parallel superposition of vibration on steady shear. The effects of vibration on the subsequent crystallization behaviors of polycarbonate(PC)/polypropylene(PP) blends were investigated. The coupling analyses by DSC and polarized light microscopy proved the nucleation in the multiple crystallization was heterogeneous. The distribution and the size of the dispersed polypropylene droplets influenced the crystallization temperature. Vibration blending reduces the size of dispersed crystallizible particles and widens its distribution corresponding to the decrease of low temperature crystallization peak and the increase of high one. However, crystallization temperature rises with nucleation rate equally due to external nucleation on the medium size particle when they are formed in relatively larger amplitude vibration blending.