喷丝板结构对中间相沥青炭纤维径向结构及性能的影响

Influence of spinneret structure on radial structure and property of mesophase pitch based carbon fibers

采用不同长径比、孔径及新型结构的喷丝板制备中间相沥青炭纤维,研究了喷丝板结构对中间相沥青炭纤维径向结构及性能的影响,利用SEM和XRD对中间相沥青炭纤维的径向结构进行表征。结果表明,大的长径比与小的孔径有利于提高中间相沥青在喷丝板中流动时受到的取向作用,得到的炭纤维径向辐射结构明显,新型结构的喷丝板有效利用了挤出涨大效应,降低了取向作用,得到的中间相沥青炭纤维具有无序型径向结构。随着长径比的增加,炭纤维微晶层间距d002逐渐减小,微晶厚度Lc逐渐增加,当长径比L/D=2时,炭纤维径向结构为无劈裂的辐射型,具有更高的力学性能。

The spinneret with different diameter, different ratio of length to diameter, and new style structure were used to spin green fibers by mesophase pitch, and the relation between structure of spinneret and cross-section texture of the fibers was studied. The cross-section texture of the fibers was investigated by SEM and XRD. The results indicated that spinneret with large ratio of length to diameter and smaller diameter was favorable to enhance the orientation effect of mesophase pitch. And the cross-section texture of the fibers was more easily showing radial texture. The new style spinneret was easy to generate ＇ Barus Effect＇ and the orientation of mesophase pitch decreased and the cross-section texture of the fibers showed randow texture. With increase of ratio of length to diameter,d002 decreased gradually and Lc increased. The cross section texture of the fibers were better when L/D was 2, and the tensile strength of the fibers increased.