Coating technology: six test methods of defoamer and four factors of the length of defoaming time

Core tip: defoamer, also known as defoaming agent, is to reduce the surface tension during food processing, inhibit foam production or eliminate foam additives In China, 7 defoamers are permitted, such as emulsified silicone oil, high carbon alcohol fatty acid ester complex, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropanol amine ether, polyoxypropylene glycerin ether, polyoxypropylene polyoxyethylene glycerin ether and polydimethylsiloxane After defoamer manufacturers produce defoamer for coating, in order to ensure product quality, we need to check the performance, and list the following six inspection methods for you Paint knowledge | precautions for wall paint color selection Recommended introduction: when painting the wall, the owner sometimes has difficulty in choosing what color of the wall paint to paint In fact, there is no ugly color in the wall paint, only the disharmonious color matching The use of wall color contains the knowledge of health Too strong color will stimulate people's perception, make people have a sense of fidgety, affect people's mental health Grasp the basic principles of wall color and paint a colorful space 1、 Wall paint color selection notice 1 Light color is generally used for the top surface Light colors make people feel light, dark colors make people feel heavy Usually, the treatment of rooms is from top to bottom, from shallow to deep For example, the ceiling and walls of rooms are white and Paint Home News: defoamer, also known as defoaming agent, is to reduce the surface tension in food processing, inhibit foam to produce or eliminate foam additives In China, 7 defoamers are permitted, such as emulsified silicone oil, high carbon alcohol fatty acid ester complex, polyoxyethylene polyoxypropylene pentaerythritol ether, polyoxyethylene polyoxypropanol amine ether, polyoxypropylene glycerin ether, polyoxypropylene polyoxyethylene glycerin ether and polydimethylsiloxane In order to ensure the quality of products, the defoamer manufacturers need to check the performance of the defoamer after they produce the defoamer for the coatings The following six inspection methods are listed as follows: first, the measuring cylinder method: adding proper amount of low viscosity paint into the measuring cylinder, adding defoamer, and observing the height of the foam every once in a while after shaking Two High speed stirring method: it is suitable for low viscosity coatings, and the foam level is measured after high speed mixing Three, gravity cup method: suitable for high viscosity coatings, paint and defoamer together to homogenizer high-speed mixing, and then determine the height and density of foam 4、 Circulation method: after coating, the remaining coating will fall into the container, and the height of the coating shall be recorded at intervals Five, bubbling method: suitable for low viscosity coatings, air will be introduced into the paint to produce foam, add defoamer regularly after the export of air, and timely recording the height of foam Six, vibration method: repeated vibration, and then foam density measurement There are four factors that affect the time of defoamer: first, the amount of silicone oil determines the consumption cycle of defoamer in use 2、 The particle size of defoamer determines the filter resistance of defoamer Too large particle size or insufficient mixing of defoamer may cause the defoamer for sewage treatment to be easily filtered out Too large particle size will cause the agglomeration of defoamer to the size of filtered particle size, and the time will be shortened, which will result in floating oil and easy filtration, so defoaming and antifoaming will have an impact 3、 The mixing time is also an important index of defoamer defoaming capacity If the mixing is not enough, the defoamer will gather together On the one hand, it is easy to agglomerate, and on the other hand, it is easy to be filtered out Now many people like to add the last defoamer when they use it If the mixing is not enough, it is likely to be turbid, bleached oil, defoaming capacity will be weakened, and the time of defoaming will be shortened If the adding sequence of defoamer for paper making is moved forward, this problem will be solved, or it can be solved by diluting with water Let the defoamer be fully dispersed in water before adding it to the system It can be solved 4、 It is related to acid and alkali resistant defoamer, because the synthesis catalyst of silicone oil in defoamer is generally acid and alkali Acid and alkali will certainly affect its decomposition rate, but adding silicate in the system will generally inhibit its decomposition Home of coatings is specialized in coatings, diatom mud, paint coating, coating technology, fire retardant coating news and coating, diatom mud, paint coating, coating technology, fire retardant coating decoration knowledge and decoration renderings,