超临界CO_2对发泡PP/木粉复合材料性能的影响

Foaming of PP/Wood Flour Composite Using Supercritical CO_2

以超临界CO2为发泡剂,对聚丙烯(PP)/木粉复合材料进行快速降压发泡,并通过扫描电镜进行泡孔形貌观测。通过控制变量法,研究了发泡温度、饱和压力、降压速率和木粉质量分数对发泡体系泡孔形貌的影响,从超临界CO2溶解过程、泡孔成核过程以及泡孔孔径增大过程三方面分别进行了分析,并结合反应条件研究了泡孔密度及泡孔孔径的变化规律及其机理。

With supercritical CO2 as foaming agent,polypropylene/wood flour composites were foamed by quick decreasing pressure method and the cell morphology was observed by transmission electron microscopy.By controlling the variable factors,the effects of foaming temperature,saturation pressure,decreasing pressure rate and the content of wood flour on cell morphology of foaming system were analyzed considering supercritical CO2 dissolution,the cell nucleation and growth.Cell density and pore size were obtained by scanning electron microscopy,and their changing rule and mechanism were investigated by considering the influence of different test conditions for supercritical CO2 foaming PP/wood powder system.