Interfacial tension measurement knowledge, this article will elaborate on interface tension measurement from concepts, equipment and methods.
First, let's understand what the interface tension is.
The interfacial tension can be regarded as the contraction force acting on the liquid interface per unit length, which is equal in value to the interface energy. Usually, the interfacial tension value is called low interfacial tension between 0.01 and 0.1 mN/m, and the interfacial tension of 0.001 mN/m or less is called ultra-low interfacial tension. The spin drop method can achieve an accuracy of 10 minus six powers and can be used to measure interfacial tension.
The interfacial tension between the interface of the solid surface and the air is the free energy of the solid surface. The materials with different solid surfaces have different surface free energies. The energy of metals and general inorganic surfaces is above 100mN/m, which is called high-energy surface. The surface of organic materials such as plastics has low energy and is called low-energy surface.
Interfacial tension measuring equipment - interfacial tension meter:
The interfacial tension measurement needs to be realized by a suitable interfacial tension meter. The optional interface tension meter can be selected from USA KINO. As a professional interface tension meter supplier, USA KINO sells the interfacial tension meter at reasonable prices and can provide comprehensive after-sales service!
Interfacial tension measurement method:
The interfacial tensiometer comprises a bubble generating unit, a pressure sensing unit, a temperature detecting unit and a display. The bubble generating unit, the pressure sensing unit and the temperature detecting unit are respectively connected to the display, and the bubble generating unit is connected to the pressure sensing unit.
The bubble generating unit comprises a capillary tube, a micro pump and a first electronic driving controller for outputting gas to the liquid surface to generate air bubbles; the micro pump is provided with an air inlet, an air outlet and a connecting head, and one end of the capillary passes through the air outlet and the micro pump Connected, the first drive controller is connected to the display;
The pressure sensing unit includes a pressure sensor and a second electronic drive controller for detecting the pressure generated by the bubble; the capillary, the air outlet and the pressure sensor are connected to each other through a tee, and the second electronic driver and the pressure sensor. Display connection
The temperature detecting unit includes a temperature detector and a temperature sensing rod for detecting the temperature of the liquid; one end of the temperature sensing rod is connected to the temperature detector, and the other end is deep inside the liquid; and the temperature detector is connected to the display.
The interfacial tensiometer can measure the dynamic surface tension as well as the static interfacial tension. It can also be used for the weighing method common contact angle meter, fiber contact angle and powder contact angle test. It is aimed at the research and development of the user in the interface chemical testing process. A specialized advanced interface chemical analysis instrument specially developed for the high-precision control of quality.
The interfacial tensiometer consists of a high-precision, high-stability force measurement system, a microcomputer control system, and a platinum plate method (Platinum Ring Method) measuring device. The instrument has advanced design, reasonable structure, automatic measurement, convenient operation and easy maintenance. The sample table is automatically lifted and lowered, the whole range can be tared (one-key clear), and the full scale is automatically corrected. The repeatability of the instrument is very good, and the test result is accurate and reliable. A sample cell thermostat and sample temperature measuring device are included to meet different test requirements.
The interface tension meter is a fast and reliable quality control mode. The surface tension value can be accurately measured and displayed after setting the measurement parameters. The ability to independently set the measurement range, the number of test data, and the average value of the measurement is an ideal tool for R&D. In actual use, the interfacial tensiometer can simulate the migration of surfactants, so it is more widely used.