接触角测量的量高法和量角法的比较

Comparison of hypsometry and goniometry in contact angle measurement

采用接触角来表征织物拒水性能更加精确,液滴角度测量法是接触角测量最常用的方法之一,量高法和量角法是角度测量最常用的方法。实际测试中发现,这2种方法测量的结果有比较大的误差,但误差产生的原因不详。从理论上对这2种液滴角度测量法的测量原理和测量误差进行比较分析,分别讨论了液滴高度、底端直径的量取误差和量角器转动误差产生的接触角测量误差,并用实验进行验证,这些实验结论和理论相符,最后证实量高法更准确、快捷、方便。

It is more precise to characterize the repellency of the fabric by contact angle. The method of measuring the contact angles between a droplet and fabric is one of the most commonly methods, whereas hypsometry and goniometry are most commonly used methods in the measurement of an angle. It is found through actual tests that these two methods results in larger measurement error, and its cause remains unknown yet. In this paper, the principle and error of these two methods were analyzed and compared theoretically. Meanwhile, the measurement error of contact angles caused by the measurement error of droplet height, the bottom diameter of droplet and the turning error of protractor were discussed, Verification experiments were performed and the results obtained are coincident with the theory. Finally, hypsometry is proved to be more precise, faster and more convenient.