材料期刊网

以聚丙烯（PP）/nano-TiO2复合材料为研究对象,采用快速降压超临界微孔发泡技术,制备了泡孔密度、泡孔直径分别为2.8×107cell/cm3~3.15×109cell/cm3,46.36μm~6.08μm的PP/nano-TiO2微孔复合材料。研究了复合材料中nano-TiO2的质量分数、饱和压力及发泡温度对PP/nano-TiO2复合材料发泡行为的影响,通过扫描电镜（SEM）对微孔形貌进行表征。结果表明,加入nano-TiO2可以改善PP的发泡性能,并得到泡孔分布均匀的闭孔发泡材料;随复合材料中nano-TiO2质量分数由1%提高到5%,泡孔密度增加,泡孔直径减小。对于nano-TiO2质量分数为3%的PP/nano-TiO2复合材料,随着饱和压力的增加,泡孔直径和泡孔密度都增加;随着发泡温度的升高,泡孔密度减小,泡孔直径变大。

This research presents the foaming behaviors of polypropylene/nano-TiO2 nanocomposites which blown with supercritical CO2 during rapid pressure reduction process. Microcellular nanocomposities with 2.8×10^7 cm-3 to 3.15×10^9 cm-3 cell density and 46.36 μm to 6.08 μm cell diameter were prepared. Through studying the effects of nano-TiO2 quality score, saturation pressure, foaming temperature on the foaming behavior of PP/nano-TiO2 composite materials, the cell structures are characterized by Scanning electronic microscopy （SEM）. The experimental results indicated that the addition of nano-TiO2 can significantly improving the foaming behaviors of PP, foaming materials with can be cell distribution more evenly of closed pore obtained. With the nano-TiO2 content increasing, the cell diameter reduced and the cell density increased, in addition, the cell distribution was more uniform. For the PP/nano-TiO2 composite materials with 3% nano-TiO2, when the saturation pressure increased, both the cell diameter and cell density increased. The cell diameter increased and the cell density decreased with the elevated temperature.