声波振动对聚丙烯腈/二甲基甲酰胺溶液流动性能的影响

运用不同功率、频率的声波分别作用于聚丙烯腈/二甲基甲酰胺(PAN/DMF)溶液,利用旋转黏度计测量其黏度,对不同振动参数处理后的溶液的流动性进行了表征,分析了振动参数对PAN/DMF溶液流动性能的影响规律,并对振动处理后的PAN/DMF溶液进行静电纺丝实验。结果表明,当频率小于20 kHz时,声波振动对溶液的流动性能几乎没有影响;当频率大于或等于20 kHz时,声波处于超声波段,振动能明显降低PAN/DMF溶液的黏度,最大降低率可达29%,显著提高了其流动性和可纺性。选择频率为21 kHz,功率为1 000 W的振动参数处理后的PAN/DMF溶液进行静电纺丝试验,纤维的平均直径由1.14μm减小为0.69μm,减小了39%。最后从理论上分析了超声波振动的降黏机理。

Effect of Acoustic Vibration on Fluidity of Polyacrylonitrile/Dimethylformamide Spinning Solution

Acoustic waves of different power and frequency were applied to polyacrylonitrile/dimethylformamide(PAN/DMF)solution respectively,and the viscosity of PAN/DMF solution was measured by using rotational viscometer.The fluidity of the solution treated with different vibration parameters was characterized.The influence of vibration parameters on the flow performance of PAN/DMF solution was analyzed by using the characterization results.Electrospinning experiments were carried out with PAN/DMF solution after ultrasonic vibration treatment.The results show that when the frequency is less than 20 kHz,the acoustic vibration has little effect on the flow performance of the solution.When the frequency is greater than or equal to 20 kHz,the acoustic wave is in the ultrasonic band,and the vibration can significantly reduce the viscosity of PAN/DMF solution,with the maximum reduction rate up to 29%,improving the liquidity and spinnability significantly.Vibration parameters with frequency of 21 kHz and power of 1 000 w are selected to vibrate PAN/DMF solution,which is used for electrostatic spinning,and the average diameter of the obtained fibers decreased from 1.14μm to 0.69μm,with a decrease rate of 39%.Finally,the viscosity reduction mechanism of ultrasonic vibration was analyzed theoretically.