分流板的结构对挤出加工中长玻璃纤维形态的影响

通过改进单螺杆挤出机，成功开发了长纤维增强聚丙烯热塑料材料在线混合技术。研究了分流板的开孔直径、开孔率、孔间距以及分流板与螺杆头部之间的距离对于长纤维形态的影响，并且测定了材料的力学性能。结果表明，当开孔直径与纤维长度之间的比值小于0.5、开孔率小于0.2时，分流板对于长纤维形态影响较大，而孔间距的变化对于长纤维形态没有影响。相对于单孔设计，分流板的多孔设计形式有利于纤维分布和进一步提高材料的力学性能。分流板与螺杆头部之间需要保持一定的距离，既能保持纤维长度又能有利于挤出。对于特定形状的分流板，局部阻力系数可以作为一个可靠的参数来控制纤维形态。

Effect of Breaker Plate Structure on Morphology of Long Glass Fiber in Extrusion Compounding

An in line compounding technique by modifying single screw extruder was proposed for manufacturing long glass fiber reinforced polypropylene thermoplastic composites. The effects of hole diameter, open hole ratio, hole pitch of breaker plate and distance between screw tip and breaker plate on the morphology of long glass fiber were studied, and the mechanical properties of the composites were tested. The results show that the breaker plate has an obvious impact while the change of hole pitch has not on the morphology of long glass fiber when the ratio of hole diameter to fiber length is below 0.5 and the open hole ratio less than 0.2. Compared to the single hole one, breaker plate with multi holes is favorable for fiber distribution and further improvement of the mechanical properties of the composites. A certain distance between the breaker plate and screw tip should be kept to maintain fiber length and stable extrusion. For a given breaker plate, the local resistance coefficient is found to be a reliable parameter to control the fiber morphology.