Current status and development trend of defoamers for waterborne coatings in China INTRODUCTION of defoamers for waterborne coatings Although the amount of additives used in water-based coatings is small, its effect is huge. Generally speaking, many problems encountered in the production, construction and application of water-based coatings can be solved by additives, among which defoamers for waterborne coatings are one of the more important additives. China is a major producer of architectural coatings, of which latex paint is the largest and most important variety. Latex paint has a large demand for defoamers, and it is increasing year by year, so the development of defoamers is very important. Before the German BYK additives entered the Chinese market, China's defoamers for waterborne coatings market was almost blank. At the same time, the magical functions of water-based paint additives began to receive approval, and Japan's Nippon Paint Company launched latex paint in C...
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The impact of the COVID-19 on the global economy and how will paper industry going? Covid-19 is still in the stage of global spread As of the evening of May 2, according to relevant statistics of the International Health Organization, there have been more than 3.27 million cases of new coronary pneumonia diagnosed globally, including a total of 230,000 deaths. The United States currently has the most confirmed cases of infection, with a cumulative total of more than 1.06 million cases. The total cumulative cases in Europe are more than 1.49 million cases, of which Spain, Italy and the United Kingdom have cumulative cases of 210,000, 200,000 and 170,000 cases, the three countries with the largest number of infections in Europe. The number of newly confirmed cases per day in Spain and Italy has shown a slowing trend. Brazil is the country with the largest cumulative number of confirmed cases in Latin America, reaching 85,000 cases, exceeding the current cumulative number of confirmed...
Is silicone oil safe? From a physiological point of view, polysiloxane is one of the polymers with the lowest known activity. The results of toxicological studies suggest that dimethyl silicone oil, which removes low-boiling substances, is non-toxic and can be used in large amounts in food, cosmetics, and pharmaceuticals. The LD50 value (50% lethal amount) of the lethal dose of dimethyl silicone oil is more than 35g/Kg. This value is classified according to the toxicity of the American Industrial Hygiene Association, which is equivalent to non-toxic; it also has no chronic poisoning problems and will not be absorbed by the digestive system. No irritation to the membrane; low viscosity dimethyl silicone oil has slight irritation to the cornea, but no harm. Safety data of silicone oil as follow: Types of silicone oil Viscosity (25 °C /mm 2 Ÿ s) Skin irritation (human) Chronic toxicity (rat, 6 ...
In many production processes, problem caused by harmful foams. The presence of these foams reduces the utilization rate of equipment, causes production losses, pollutes the environment, and even affects the normal operation of operations. To eliminate harmful foam, you can use standing, decompression (vacuum), heating or pressurization, chemical defoaming, etc. But when you need to quickly and effectively eliminate foam in a short time, you need to use chemical defoaming. Chemical defoaming does not require a lot of equipment investment and does not need to change the original process. It is the most convenient way of operation. Why are emulsion defoamers layered? Emulsion-type defoamers will delaminate if they are not used for a long time. After delamination, defoamers will affect their use. Why do they delaminate? What are the causes? Emulsion defoamers are physically emulsions and are thermodynamically unstable systems. Layering may occur after long-term storage, but use after...
Defoamers Test Method--- Fermentation Defoamer type: Silicone¨ Polyetherþ fatty alcohol ¨ Mineral oil ¨ Others ¨ 1. Defoamer performance: (Air drum test) Accurately weigh 200ml of foaming medium with a 1000ml measuring cylinder, turn on the air bubble to the specified foam and mention 800ml and record the blank time, then add the prepared defoamer sample, stir it evenly, then turn on the air bubble and record the volume V changes with time. 2. Solid content test (instrument: oven, Surface dish) Turn on the oven, set the temperature to 105°C, wash and dry the watch glass Weigh a certain amount of defoamer sample on the watch glass, and record the weight of the watch glass before and after adding the defoamer as ml and m2 Put the watch glass with the sample in the oven, close the oven after 1h, put the watch glass in the desiccator and cool it, then weigh it as m3; The solid content of the sample is: W=(m3-m1)/(m2-m1)*100% 3 . Viscosity (instrument: mechanical visc...
The global papermaking chemicals market will exceed 42 billion US dollars in 2025 Relevant data show that the global papermaking chemicals market will exceed 42 billion US dollars in 2025. Papermaking chemicals as follow: process chemicals, functional chemicals, pulping chemicals on the other hand by type, they can be divided into special chemicals, commodity chemicals, etc. Papermaking chemicals are specifically used to change paper properties, including color, strength, recycling performance, basis weight, quality, and related attributes. In order to obtain specific functions, the paper undergoes various processes such as bleaching, beating, strengthening and sizing. In order to further improve paper quality and improve multiple functions, people in the industry continue to improve the performance of paper, and it is expected that the scale of the chemical industry will be further promoted in the next few years. Why does paper chemicals has been increasing? As the pursuit of paper fi...
How should we select defoamers / antifoams for paper pulp? Pulp and paper antifoaming agents is very necessary in papermaking, because a lot of foam will be generated in the process of papermaking and pulping, the surface tension of the generated saponification is less than the surface tension of black liquor produced by cooking materials, making it It exists in the surface layer of black liquor and forms a thin film, which forms foam under the mixing action of air. The papermaking process is mainly divided into two major steps, Washing pulp Papermaking No matter which step inevitably produces foam, so you need to use defoamers/antifoam for paper industry, there are many types of defoamers, the following is for everyone Introduce the characteristics of papermaking defoamers. Excessive foaming will result in the loss of fibers and raw materials. Further, the presence of air in the wet paper web can affect the filtration rate of paper in the paper making pulp defoamers is a better s...
The epidemic situation of the new coronavirus in China has been effectively controlled, but coronavirus has already broken out in other regions of the world. In addition to our country, Italy has also set up blockade and isolation measures. Potential negative demand impact-FMCG growth slows Worries about the virus are likely to affect consumer consumption patterns. From the perspective of pulp and paper, this trend will most directly affect packaging demand. In the past, the post-holiday recovery difficulties caused by the virus in our country, the large-scale loss and even the closure of the tertiary industry such as catering, tourism, and supermarkets, as the virus entered other major countries (the Western country ’s tertiary industry accounted for a larger proportion May be more prominent), consumers may exhibit similar behavior. Trend chart of the proportion of employment of tertiary industry in China Trend char...
Why does foam generate in biochemical water treatment process? Chemical foam (starting foam) It is formed by the agitating and blowing off the surface active substances in the wastewater. In the initial stage of activated sludge cultivation, there are many chemical foams, and sometimes foam hills up to several meters are formed on the surface of the aeration tank. This is mainly because the initial activated sludge has not yet formed, and all the foam-generating substances form foam under the action of aeration. With the increase of activated sludge, a large amount of surface active substances are absorbed and decomposed by microorganisms, and the foam will gradually disappear. Chemical foam is milky white, easy to handle, can be filled with water to defoam, or defoamer has been added. Denitrifying foam If the nitrification reaction is carried out in the sewage plant, denitrification will occur in the sedimentation tank or in ...