Method for measuring liquid-drop contact angle on solid surface and device thereof

Abstract

The invention relates to a method for measuring a liquid-drop contact angle on a solid surface and a device thereof, which are used for measuring the contact angles of the liquid drops with different mediums and different sizes on the solid surface. The method comprises the following steps of: according to one-to-one correspondence between a liquid drop volume and a liquid drop contact angle, obtaining a plurality of liquid drop profiles which correspond to different contact angles, thus establishing a database used for storing different liquid drop profiles; when in measuring, fixing a sample on an earthquake isolation platform, and dropping the liquid with known volumes on the surface of the sample by utilizing a micro-injector; after the liquid drops achieve balance, acquiring a liquiddrop image on the surface of the sample by utilizing an optical imaging system, a CCD camera and a computer; utilizing an image matching method to carry out processing and analyzing to the shapes of the liquid drops by computer software, and then carrying out calculation to obtain contact angles of the liquid drops; and matching the liquid drop profiles obtained by experimental measurements with the liquid drop profiles in the database so as to determine the corresponding contact angles. Compared with the existing method, the method takes the influence of volume and weight of the liquid drop in to consideration, thus improving the measuring precision.

Description

Method and device for measuring droplet contact angle on solid surface technical field The invention relates to a method for measuring the contact angle of liquid droplets, which is used for accurately measuring the contact angles of liquid droplets of different media and sizes on solid surfaces, and belongs to the technical field of measurement. Background technique The interfacial wetting properties characterized by various materials, including organic matter, inorganic substances, and liquid metals, are the focus of research in the field of modern physical chemistry, and the contact angle is an important parameter to characterize the interfacial wetting properties. At present, even the most advanced contact angle measuring instrument in the world cannot give the value of the contact angle very well when the droplet is relatively large or the contact angle is relatively large (such as superhydrophobic materials). A large error occurred. One of the main reasons for the e...

AI Technical Summary

Problems solved by technology

At present, even the most advanced contact angle measuring instrument in the world cannot give the value of the contact angle very well when the droplet is relatively large or the contact angle is relatively large (such as superhydrophobic materials). big error

One of the main reasons for the error is that the influence of gravity is not considered when measuring the contact angle, and the influence of the volume change on the droplet profile is not considered. Therefore, the measurement accuracy is not very good, and the measurement error ranges from 5 to 10°

However, the liquid droplets in the actual measurement are often affected by gravity. For liquid metals, even if the volume is small, the influence of gravity cannot be ignored.

Images