超声振动在PS挤出发泡中的作用研究

研究了在ＰＳ挤出发泡中引入高强度超声振动对制品微观形貌和性能的影响。结果表明在ＰＳ挤出发泡的机头熔体中加入超声波可提高发泡率，降低发泡制品的密度，螺杆转速越低时更为明显，泡孔形貌由原椭园变为园形，从而补偿由密度降低引起的拉伸强度下降，在机头熔体中加入超声波能降低挤出压力，提高挤出产量，但不如超声振动加入到模具和熔体界面时明显，在螺杆转速较高时，总消耗功率比低转速时有所降低

The Effect of Ultrasonic Oscillation on PS Extrusion foaming

The effect of high intensive ultrasonic oscillation on the microphotography and property of extruded PS foamed product was studied. The results showed the application of ultrasound to the melt in the head could increase the foaming cappacity, decrease the foam density of the product, which would be more obvious when the screw rpm was low. The cell geometry changed from ellipse to round, compensating the tensile strength decrease caused by density decrease. The application of ultrasound to the melt in the heat could also lower the extrusion pressure, increase the extrusion rate, but it was not obvious as the application of ultrasound in the interface between the mould and melt. The total power consumed at high screw rpm was lower than that at low screw rpm.