压缩和回弹及极板放置对棉纤维电阻测试的影响

Effect of compression,resiliency and electrode location on measurement of electrical resistance of cotton fibers

利用自制的纤维压缩装置研究棉纤维集合体电阻测试过程中压缩和回弹以及极板放置方式对测试数据的影响,为提高棉纤维回潮率和电阻测试的准确性和重现性提供参考。通过实验发现:测试时棉纤维集合体的电阻与体积密度近似成反比关系;纤维体积密度较大时,纤维集合体的密度可以通过压缩和压缩后回弹2个过程得到,在相同体积密度条件下,压缩过程的体积电阻率小于回弹过程的体积电阻率;棉纤维集合体沿压缩方向的体积电阻率与沿垂直压缩方向的体积电阻率之间存在一定的差异,随着体积密度的增加,二者的差异有一定增加。在10 V测试电压下,沿垂直压缩方向的体积电阻率相对较小。体积密度比较大时有利于棉纤维的电阻测试。棉纤维集合体在压缩过程中测试才能获得准确和稳定的数值。

The self-made fiber compression device was designed to investigate effect of compression and resiliency process and electrode location on electrical resistance measurement of cotton fiber assembly. It is intended to make reference for improving the accuracy and reproducibility of the measurement of moisture regain and electrical resistance of cotton fibers. The experimental results revealed that electrical resistance of cotton fiber assembly is approximately inverse proportion to the volume density of the fiber assembly. At higher density of fiber assembly, density of fiber assembly can be obtained by compression and resiliency. At the same density of fiber assembly, volume resistivity in compression process is less than that in resiliency process. There is difference between volume resistivity of cotton fiber assembly in compression direction and in the direction vertical to compression direction. With the increase of density, the difference between them increases to some extent. At applied voltage of 10 V, volume resistivity of cotton fiber assembly in compression direction is larger than that in the direction vertical to compression direction. Higher density of fiber assembly is in favor of resistance testing for cotton fiber assembly. Stable and accurate results can only be obtained in compression process.