Introduction of Instrument

SZ-CAMC33 contact angle measuring instrument is mainly used to measure the contact angle of liquid to solid, i.e., the wettability of liquid to solid.The instrument can measure the contact angle of various liquids on various materials, such as lumpy materials, fiber materials, textile materials, etc. Powder samples can also be measured after pressing.

This instrument tests static contact angle by stop-drop method, dynamic contact angle by tilting plate method, liquid surface tension by hanging drop method, and solid surface energy by surface energy estimation model.

Working Principle

At the junction of solid, liquid and gas phases, the angle between the solid-liquid interface passing through the liquid interior to the gas-liquid interface is called the contact angle, also known as the infiltration angle.When a droplet is placed on a smooth and uniform horizontal surface, it may diffuse onto the substrate and the contact angle will approach zero if complete wetting occurs;Conversely, if the wetting is partial, the resulting contact angle equilibrates within the range of the material's surface energy.The smaller the contact angle, the greater the wettability or surface energy of the substrate.

A drop of the liquid to be measured is placed on the substrate with a syringe needle, the drop adheres to the surface of the substrate and casts a shadow, the projection screen micrometer projects the image onto the screen using optical magnification, and the contact angle is determined by recording the image of the drop and automatically analyzing the shape of the drop, using a drop profile fitting method to analyze the image obtained.

Explain: Jikun Yin,2023 PhD

Photograph: Yuqing Liu, 2022 master-Mingmin Li’s team

Montage: Xuejie Jiang, 2022 master-Peng Zhang’s team