Recently, covid 19 outbreak spreads in Shanghai, China. There are more than 25,000 new asymptomatic domestic infections every day. China is implementing a dynamic zero-out policy. A leading respiratory expert said the key to COVID-19 prevention and control is to minimize transmission and fatality rate. Omicron has a low case fatality rate but is highly transmissible and can still claim many lives in large outbreaks. "Total openness is not applicable in China. For China, we should keep to the dynamic zero-out and gradually open up."
However, "dynamic zero clearance" is not the pursuit of complete "zero infection". As the Novel Coronavirus has its own uniqueness and strong concealment, there may be no way to prevent the detection of cases at present, but rapid detection and prompt treatment must be carried out, as soon as one case is found, one case will be dealt with.
The situation in Shanghai is serious. As the financial center of China, Shanghai is a very important city, and the outbreak of the epidemic in Shanghai will put a great impact on China's economy. The current task is to contain the spread of the epidemic as soon as possible, to achieve social zero so that Shanghai's life and economy quickly return to normal.
As China plays an important role in the global supply chain, the outbreak will have a significant impact on the supply and prices of many Melamine Series Water Reducing Agent.
Introduction to Melamine Series Water Reducing Agent:
High-efficient water reducing agent is also known as superplasticizer, whose water reducing rate is not less than 14%. It includes the naphthalene type, melamine type, amino sulfonate type, aliphatic type, etc.
Melamine water reducing agent is the product of the reaction that melamine is first sulfonated by sulfuric acid and then condensed with formaldehyde, so the chemical name is sulfonated melamine-formaldehyde resin, which belongs to the anionic surfactant. The appearance of this kind of water-reducing agent is white powder. It is soluble in water, and it has a good dispersion effect on powder materials, a high water reduction rate, good fluidity, and good self-repair.
Preparation method of Melamine Series Water Reducing Agent:
The synthesis principle of the melamine system high-efficient water reducing agent is in the alkaline medium to make formaldehyde and melamine form carbon positive particles, which will then be condensed in the acidic medium, connect to the long-chain structure, at the same time to provide amino sulfonic acid molecular structure contains a certain number of the polar sulfonic acid root, increase points enhanced. Due to the active chemical properties of the substances involved in the reaction, the reaction temperature, reaction speed, and the proportion of reactants have a significant impact on the performance of the product, so it is key to seek the appropriate proportion of reactants, reaction temperature, and reaction speed. Composition ratio: melamine: formaldehyde: sulfamic acid =1: (3.5-4.0) : (2 ~ 2.5); The reaction temperature is controlled at 75-80 ℃ in the first stage and 45-60 ℃ in the second stage. The reaction time is 1.5 -- 3 h, and the product has good performance and the lowest production cost. In the production process, by adding a reflux device, a reactor series reaction is realized, which simplifies the production process and eliminates the generation of "three wastes".
Applications of Melamine Series Water Reducing Agent:
Melamine series of high efficient water reducing agent products have been used in precast components factories, commercial concrete mixing stations, and other units. The users of the component factory generally report that the working performance of concrete is greatly improved, and the setting of the components to be steamed is greatly shortened. Users of the mixing station also reflect that the product has strong adaptability to cement, which can effectively improve the poor workability of concrete due to poor aggregate quality, and the pumpability is greatly improved, which solves the pumping tie down the problem at 150 m height. The melamine system high-efficient water reducing agent can be used as a single admixture, and it is more suitable for the use of the complex. A series of experiments show that the melamine high-efficient water reducing agent can be used in combination with other series of high-efficient water-reducing agents, and the performance is improved. According to the appropriate ratio of chaff cutter after the platform, the effect of reducing water appears superposition effect, especially for the cement material amount of concrete no longer invite stick, grasp the bottom phenomenon, so suitable for the preparation of high strength and high-performance concrete. The product if the addition of lignin or hydroxyl carboxylic acid retarder, you can compound a good performance of pumping agent, with the pumping agent prepared by the commercial concrete workability is good, plastic effect is significant, pumping performance is greatly improved.
Suppliers of Concrete Additives
TRUNNANO is a reliable concrete additives supplier with over 12-year experience in nano-building energy conservation and nanotechnology development. If you are looking for high-quality concrete additives, please feel free to contact us and send an inquiry. (email@example.com)
We accept payment via Credit Card, T/T, West Union, and Paypal. Trunnano will ship the goods to customers overseas through FedEx, DHL, by air, or by sea.
As the duration of the conflict between Russia and Ukraine grows, its impact on commodities is widening amid the tug-of-war. Recently, European and American sanctions against Russia have been issued one after another. In response, Russia has taken advantage of its role as an important supplier of many energy and commodities, requiring exports of commodities, including energy, grain, metal, and wood, to "unfriendly" countries to be settled in robles. Therefore, it is expected that the price of the Melamine Series Water Reducing Agent will continue to increase.
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