【摘要】 采用三维有限元数值模拟方法,研究了聚丙烯(PP)/无机纳米粒子在双螺杆挤出机的三种螺杆组合元件流道内的分散混合效果。通过对比分析三种螺杆组合下无机纳米粒子的剪切应力和剪切速率、停留时间分布及粒径分布等结果,发现含错列角45°捏合块的螺杆组合对其流场中大部分粒子的剪切作用最强,含错列角60°捏合块的螺杆组合次之,含错列角90°捏合块的螺杆组合最弱。与另两种螺杆组合相比,含错列角45°捏合块的螺杆组合流场中,无机纳米粒子团聚体的数量最少,剥离出的碎片数量最多,即在含错列角45°捏合块的螺杆组合条件下无机纳米粒子在PP熔体中的分散效果最好。更多还原

【Abstract】 Using a three-dimensional finite element numerical simulation method，the dispersion and mixing effects of polypropylene (PP)/nano-inorganic particles in the flow passages of three screw combination elements of twin-screw extruder were studied.Through comparative analysis of the shear stress and shear rate，residence time distribution and particle size distribution of nano-inorganic particles under the three screw combination elements，it is found that the screw combination containing kneading blocks with a staggered angle of 45° has the strongest shearing effect on most of the particles in the flow field，followed by the screw combination containing kneading blocks with a staggered angle of 60°，and the screw combination containing kneading blocks with a staggered angle of 90° is the weakest combination.Compared with the other two screw combinations，the screw combination containing kneading blocks with a staggered angle of 45° has the least amount of nano-inorganic particle agglomerates in the flow field and the largest number of stripped fragments，which indicates the dispersion effect of nano-inorganic particles in the PP melt turns out to be the best under the conditions of screw combination containing kneading blocks with a staggered angle of 45°.更多还原