The foaming agent is a substance that makes the target substance pore. It is divided into three categories: the physical foaming agent, surfactant, and chemical foaming agent. The physical foaming agent is detected through analysis, that is, the pores of the foam are formed by the change of the physical form of a substance, that is, the expansion of the compressed gas, the volatilization of the liquid, or the dissolution of the solid; the foaming agent has a high surface Activity, can effectively reduce the surface tension of the liquid, and arrange the double electron layer on the surface of the liquid film to surround the air to form bubbles, and then form a foam from a single bubble; chemical foaming agents are those that can release carbon dioxide and nitrogen after being decomposed by heating Gases and compounds that form fine pores in the polymer composition.
At present, most of the enterprises engaged in the production of foamed concrete are small enterprises without professional laboratories and testing equipment. Therefore, in actual production, most enterprises are difficult to adopt the formal methods prescribed by the relevant industry standards, and the actual quality control of physical foaming agents will bring many inconveniences. So, you know how to perform simple physical foaming agent detection
First, take an empty bottle, which is about the same thickness as the top and bottom. Use a syringe needle to extract 30 ml of purified water and pour it into the bottle.
Take another 1 mm needle, extract 1 mm of physical foaming agent for measurement, inject 30 ml of water, shake the bottle dozens of times, and inject a lot of foam into the bottle. After standing for 2 minutes, measure the height with a ruler and record it. The height is the foaming height, and the foaming ability can be measured.
After 1 hour, the foam height is measured again. Compared to the previous height, the difference between the two heights is the foam settling distance. The height of the bleeding at the bottom of the bottle is measured once, as the bleeding value, and can also be used as a reference value for the stability of the foam. The larger the bubble drop value and bleeding value, the worse the quality. For accuracy, the test should be repeated 3 to 5 times, at least three times, and an average of 3 times.
The foam prepared above is tested for cement suitability. Many foams produced by foaming agents are very stable when used alone. Once in the cement slurry, the defoaming speed is very fast and may not be suitable for cement. Or adapt to this cement, not another glue. Therefore, cement suitability testing must be performed.