摘要
采用双螺杆挤出机安装狭缝机头,在聚丙烯(PP)熔体中注入发泡剂进行在线流变实验,研究不同含量的二氧化碳(CO_2)、CO_2/乙醇、CO_2/水对PP剪切黏度的影响。结果表明,3种发泡剂溶解进入PP,质量分数相同的情况下,水对PP塑化程度最高,CO_2次之,乙醇最低,由实验推导出了不同工艺条件下PP/复合发泡剂体系剪切黏度计算公式。
The on-line rheological behavior of polypropylene and composite blowing agent were studied by using a twin extruder with slit die. The effects of different contents of carbon dioxide(CO_2),CO_2/ethanol and CO_2/water on the shear viscosity of PP were investigated. The experimental results demonstrate that under the same mass fraction of blowing agent dissolved into PP melt,water had the highest degree of plasticization to PP,followed by CO_2,and ethanol was the lowest. The equations of shear viscosity of PP & composite blowing agent system were deduced based on the experiment data under different technological conditions.
引文
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