静电纺丝参数对镁铝尖晶石纤维制备的影响

摘要

This work aims at obtaining continuous nano-diameter magnesium aluminate spinel fibers.Firstly, magnesium aluminate spinel precursor dry gel was synthesized by the non-hydrolytic sol-gel method using non-aqueous magnesium chloride,non-aqueous aluminum chloride,absolute alcohol and methylene chlo-ride as starting materials.Then electrospinning precursor solution was prepared by adding absolute alco-hol,polyvinyl pyrrolidone (PVP)as spinning aid,ethanol and N,N -dimethyl formamide (DMF)as solvent into the precursor dry gel.Finally precursor fibers were prepared via electrospinning technology and then calcined at 900 ℃.The influences of the spinning voltage (12,15,and 18 kV),spinning flow rate (0.8,1.1, and 1.4 mL·h -1 )and the needle diameter (0.6,0.8,and 1.2 mm)on preparation of magnesium alumi-nate spinel fibers were studied.The results show that the electrospinning voltage and flow rate have great influence on the morphology of magnesia alumina spinel fibers but mild influence on the fibers phase com-position;the needle diameter influences the diameter and morphology slightly;but when the needle aver-age diameter is 1.2 mm or above,a little periclase exists.The optimized spinning parameters are the elec-trospinning voltage of 15 kV,the electrospinning flow rate of 0.8 mL·h -1 ,and the needle diameter of 0.8 mm;and the obtained fibers have diameter of 50 -250 nm and the average of 121 nm.%为了制备直径为纳米级的镁铝尖晶石连续纤维，以无水氯化铝、无水氯化镁、无水乙醇和二氯甲烷为原料采用非水解溶胶－凝胶法制备镁铝尖晶石前驱体干凝胶，再加入无水乙醇、聚乙烯吡咯烷酮（PVP）和 N，N －二甲基甲酰胺（DMF）制成静电纺丝液，然后采用静电纺丝法制备镁铝尖晶石前驱体纤维，最后经900℃煅烧制成镁铝尖晶石纤维，主要研究了静电纺丝电压（12、15、18 kV）、进料流速（0．8、1．1、1．4 mL·h －1）及纺丝针头直径（0．6、0．8、1．2 mm）对镁铝尖晶石纤维相组成和形貌的影响。结果表明：1）纺丝电压和进料流速对镁铝尖晶石纤维相组成影响不大，但对纤维形貌影响较大；纺丝针头直径对镁铝尖晶石纤维直径及形貌影响不大，但当纺丝针头直径增大至1．2 mm 时，纤维中含有少量方镁石。较优的纺丝参数为：纺丝电压15 kV，进料流速0．8 mL·h －1，针头直径为0．8 mm；以较优纺丝参数制得的镁铝尖晶石纤维的平均直径为121 nm，直径分布在50～250 nm。