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Among the additive components, the defoamer should be a small material with the lowest use frequency and addition amount. The smaller the size of the study, the more difficult it is, and the less universal the experimental data and conclusions are. Differences in concrete materials, water reducing agent materials, and defoamer types may make the experimental results have no laws or even point to the opposite direction of theory and experience.Let's start with a conclusion that has been fully verified by a lot of experiments and supported by theory: the workability of concrete will deteriorate with the increase of the amount of defoamer, while the strength of concrete will increase.Once in the mixing station customer to make a test, I raised the defoamer from 0.01% of the applied dose to 0.03% after the concrete workability significantly reduced. Therefore, based on past experience, I am also very cautious about the use of defoamer, and I am very worried about the deterioration of concrete workability.Recently, however, modified air entraining agents have been developed, so the effects of the amount of defoamer on the workability of concrete have been systematically tested several times. The results are strange, but they stand up to verification. After several tests, I have a new view on the use of antifoaming agents. Test purpose 1. Compare the influence of different dosage of ether defoamer on concrete Experimental design 1. The types and amounts of other raw materials in the fixed admixtures are unchanged, and only the amount of ether defoamer is changed for concrete adaptation comparison.

Carboxymethyl Cellulose Carboxymethyl Cellulose (CMC) is a water-soluble cellulose ether obtained by chemical modification of natural cellulose. Sodium carboxymethyl cellulose is referred to as CMC-Na, white to light yellow powder, granular or fibrous substance, strong hygroscopic, easily soluble in water, in neutral or alkaline, the solution is a high viscosity liquid. Stable for drugs, light and heat. However, the heat is limited to 80 ° C, and the long-term heating above 80 ° C reduces the viscosity and is insoluble in water. [3] The relative density is 1.60 and the relative density of the flakes is 1.59. Refractive index 1.515. It is brown when heated to 190 ~ 205 ° C and carbonized when heated to 235 ~ 248 ° C. Its solubility in water depends on the degree of substitution. Insoluble in acid and alcohol, salt does not precipitate. It is not easy to ferment, has large emulsifying power for grease and wax, and can be preserved for a long time. Widely used in petroleum industry digging mud treatment agent, synthetic detergent, organic washing aid, textile printing and dyeing sizing agent, daily chemical products water-soluble viscosifier, pharmaceutical industry viscosifier and emulsifier, food industry thickener, ceramic industry adhesive, industrial paste, paper industry sizing agent and so on. It is used as a flocculant in water treatment, mainly for wastewater sludge treatment, and can improve the solid content of filter cake. Sodium carboxymethyl cellulose is also a thickener, because of its own good functional properties so that it has been widely used in the food industry, it also to a certain extent to promote the rapid and healthy development of the food industry. For example, because it has a certain thickening and emulsifying effect, it can be used to stabilize acid milk drinks and increase the viscosity of yogurt system; Because of its hydrophilic and rehydrophilic properties, it can be used to improve the edible quality of bread and steamed bread, prolong the shelf life of pasta products and improve the taste. Because it has a certain gel effect, it is conducive to the better formation of food gel, so it can be used in the manufacture of jelly and jam; It can also be used as an edible coating material, combined with other thickening agents, applied on the surface of some food, can maximize the preservation of food, and because it is an edible material, it will not cause adverse effects on human health. Therefore, edible grade CMC-Na, as an ideal food additive, is widely used in food production in the food industry. Except CMC, Santochem has many other different types of cellulose ethers, for pharmaceutical use, Hydroxypropyl Methyl Cellulose can be used as thickener, dispersant, emulsifier and film-forming agent. It can also be used as water retaining agent for tile adhesive in dry mix mortar. For concrete admixtures, we have high efficiency water reducer including Polycarboxylate Superplasticizer.

Polycarboxylate Superplasticizer (Polycarboxylate Superplasticizer) is a high performance water reducing agent, which is a cement dispersant in the application of cement concrete. Widely used in highways, Bridges, DAMS, tunnels, high-rise buildings and other projects. The product is green, non-flammable, non-explosive, and can be safely transported by train and car. In many concrete projects, traditional high efficiency concrete such as naphthalene series can not meet the engineering needs more and more due to the limitation of technical performance. A new generation of water reducing agent that has attracted much attention at home and abroad, polycarboxylic acid series high performance water reducing agent, because it has truly designed an effective molecular structure according to the action mechanism of dispersed cement, has a super-dispersed type, can prevent the loss of concrete slump without causing obvious retarding, and plays a high plasticizing effect under low content. Good fluidity retention, cement to adapt to a wide range of molecular structure, large degrees of freedom, synthesis technology, high performance of a large room for strengthening concrete significantly, can reduce concrete shrinkage, harmful substance content is very low technical performance characteristics, The concrete is endowed with excellent construction workability, good strength development, excellent durability, polycarboxylic acid series of high-performance water reducer has good comprehensive technical performance advantages and environmental protection characteristics, in line with the needs of modern concrete engineering. Therefore, polycarboxylic acid series high performance water reducing agent is gradually becoming the preferred admixture for the preparation of high performance concrete. It is reported that the use of polycarboxylic acid admixtures in Japan has accounted for more than 80% of the total number of high-performance admixtures, and North America and Europe have also accounted for more than 50%. In China, polycarboxylic acid superplasticizers have been successfully applied only in the Three Gorges Dam, Sutong Bridge, Tianwan nuclear power plant, Beijing-Shanghai high-speed railway and other large national water conservancy, bridge, nuclear power, railway projects, and achieved remarkable results. [5] At the same time, polycarboxylic acid superplasticizer also has some problems: 1. The slump retention under high temperature environment is insufficient; 2. Strong temperature sensitivity, the construction of the same polycarboxylic acid superplasticizer in different seasons, the slump retention of concrete is very different; 3. With fewer functional products, it is difficult to meet the requirements of ultra-high and ultra-long distance concrete pumping, negative temperature construction, preparation of ultra-early strength concrete and high durability of concrete; 4. High viscosity, in the preparation of high blend material and low water-binder ratio concrete, the concrete viscosity is high, which is not conducive to construction; 5. Strong sensitivity to the mud content of sand and stone aggregate. [2] The adaptability to machine-made sand is also poor, and the sensitive content affects the construction. Good compatibility with all kinds of cement, good slump retention performance of concrete, extend the construction time of concrete. 2, low content, high water reduction rate, shrinkage. 3, greatly improve the early and late strength of concrete. 4, this product has low chloride ion content and low alkali content, which is conducive to the durability of concrete. 5, the production process of this product is pollution-free, does not contain formaldehyde, in line with ISO14000 environmental protection management international standards, is a green environmental protection products. 6, the use of polycarboxylate water reducer, more slag or fly ash can be used to replace cement, thereby reducing costs. Except PCE, concrete formula also need other additives such as defoamer, air-entraining agent, fibers, retarder and so on.

PCE ST605 for Prefabricated Components The effect of prefabricated components and prefabricated polycarboxylate superplasticizer ST605 on the performance of concrete is studied from this text. The results show that concrete mixed with ST605 has the shortest setting time and the highest surface brightness. The early strength of concrete 24h can be increased by 40% compared with that of SNF superplasticizer concrete. The appropriate amount of superplasticizer is beneficial to the early strength growth of concrete, which can better meet the construction requirements. ST605 can effectively reduce the bleeding rate of concrete and improve the durability of concrete compared with ordinary PCE. Compared with SNF superplasticizer, it can improve the quality of prefabricated components, reduce the production cost and increase the economic benefit. Raw materials and testing methods: 1.1 Raw Materials (1) Cement P.O42.5R ordinary Portland cement; The fly ash is Grade I ash. (2) The fineness modulus of machine-made sand is 2.7, the content of stone powder is 12%, and the methylene blue is 2.1; The plastic gravel of small stone 5~10mm and large stone 10~20mm is used in combination, the needle flake is less than 5%, and the crushing value is less than 15%. (3) Tap water is used for mixing water. (4) Water reducing agent –SANTOCHEM ST605. Testing method: Refer to the test methods specified in the relevant standards for the performance and durability of concrete mixes. Results and discussion: It is found that the concrete with other water reducing agents has longer setting time, the initial setting time is 6h, the final setting time is 8.5h. The setting time of concrete mixed with st605 is shortened, the initial setting time is 4h, and the final setting time is 5.5h. It is beneficial to speed up the mold removal, improve the mold turnover rate, and greatly increase the surface brightness. The reason for this effect is that, in terms of mechanism, compared with other water reducing agents, ST605 main chain can completely cover the surface of cement particles, so the covered part is hydrated, and with the increase of alkalinity, electrostatic repulsion and steric hindrance are destroyed to accelerate the hydration reaction, thereby shortening the setting time of concrete, and a large number of polymers are introduced to improve the surface brightness.  Effect of ST605 water-reducing agent on the early strength of prefabricated components: The early strength of the prefabricated component is related to the turnover efficiency and lifting quality of the formwork, so the influence of the type of water reducing agent on the early strength of the prefabricated component is studied. The strength growth rate of the prefabricated component with ST605 superplasticizer was faster than that of ordinary polycarboxylic acid superplasticizer and naphthalene series superplasticizer within 24h. The 8h strength of the concrete with ST605 superplasticizer reaches 3MPa, while the naphthalene superplasticizer concrete has no strength when approaching the final setting. When the concrete meets the strength of removal and lifting (the design strength of concrete is 50% and above), the concrete with ST605 water reducing agent only needs 19h, while the naphthalene water reducing agent concrete needs more than 24h, and the strength of ordinary polycarboxylic acid water reducing agent concrete just reaches 50%. Considering the slight fluctuations of raw materials, the production strength should leave a surplus value. The concrete mixed with ST605 water reducing agent grows faster than naphthalene type water reducing agent, and the strength reaches more than 15MPa at 19h, which is about 6h earlier than naphthalene type water reducing agent concrete, speeding up the turnover efficiency of formwork and shortening the production cycle. Testing Conclusion Concrete with ST605 Polycarboxylate Superplasticizer in production has good maintenance performance, good working performance and easy construction; Shorten the production cycle, increase the number of production, can reduce the production cost; High early strength can optimize raw material costs and increase economic benefits. Meanwhile, Santochem has different types of concrete admixtures to meet different requirements of customers, for example some customers are from extreme cold region like Russia, in this case we provide customers with anti-freezing agent, including Nitrite; while some customers need early strength agent, we have Calcium Formate here.  

Basic Concepts and Classification of Cellulose Ether 1. basic concepts of cellulose ether In dry mortar, the addition of cellulose ether is very low, but it can significantly improve the performance of wet mortar, which is a major additive that affects the performance of mortar construction. Main additives include HPMC, MHEC, RDP, HPS, PVA etc. The cellulose ether is mainly made of natural fiber, and is processed by alkali dissolution, graft reaction(etherification), water washing, drying, grinding and so on. As the main raw material, natural fiber can be divided into cotton fiber, cedar fiber, beech fiber and etc. Their degree of polymerization will affect the final viscosity of their products. At present, the main cellulose manufacturers all use cotton fiber(the by-product of nitrocellulose) as the main raw material. Cellulose ether can be classified into ionic and nonionic types. The ionic type mainly includes carboxymethyl cellulose salt, and the nonionic type mainly includes methylcellulose, methyl hydroxyethyl (propyl) cellulose, hydroxyethyl cellulose and so on. 2. the classification of cellulose ether In dry mortar, since ionic cellulose (carboxymethyl cellulose salt) is unstable in the presence of calcium ions, it is rarely used in dry powder products in which cement, slaked lime used as a cement material. In some places of China, some indoor putty that made of modified starch as the main cementing material and double flying powder as a filler, carboxymethyl cellulose salt is used as thickener. This product is prone to mildew and is not resistant to water, so it is now being phased out. Hydroxyethyl cellulose is also used in some dry powder products, but it has a very small market share, and will not be described in detail here. Now, the cellulose ether used in dry mortar are mainly methyl hydroxyethyl cellulose ether(MHEC) and methyl hydroxypropyl cellulose ether(MHPC), which account for more than 90% of the market share, and the proportion of real methyl cellulose ether is very low. The article refers to methyl cellulose ether, mainly about MHEC and HPMC. Water retention is an important property of methyl cellulose ether, and it is also a concern of many domestic dry powder manufacturers, especially those in the south area with high temperature. Factors that affects the water retention effect of the mortar include the amount of HPMC, the viscosity of HPMC, the fineness of the particles, and the temperature of the environment in which it is used. 1. Effect of added amount on water retention The water retention capacity of the mortar increases with the addition of methyl cellulose ether. 2. Effect of viscosity on water retention The water retention effect of HPMC improved with the increase of viscosity. 3. Effect of fineness on water retention The water retention performance of HPMC is also related to the fineness of the particles. Generally speaking, the water retention performance of good fineness of HPMC is better than the coarse HPMC. 4. Effect of temperature on water retention The water retention of HPMC is also related to the temperature. The water retention of methyl cellulose ether decreases with the increase of temperature. However, in practical material applications, mortars are often applied to hot substrates at high temperatures(above 40℃), such as exterior putty plastering in the sun during summer, which often accelerates the curing and hardening of the concrete. The decrease of water retention rate has led to a significant influence for both workability and crack resistance, so reducing temperature factors under such conditions becomes particularly critical. The above environment forces mortar formulators to make special compensation and make many important changes in seasonal formulations. Although methyl hydroxyethyl cellulose additives are currently considered to be at the forefront of technological development, their dependence on temperature still results in a decrease in mortar performance. Despite increasing the amount of methyl hydroxyethyl cellulose(summer formulation), workability and crack resistance are still not sufficient for use. By special treatment of MC, such as increasing the degree of etherification, it can maintain its better water retention effect at higher temperatures, and it can provide better performance under harsh conditions. Except additives for dry mix mortar, Santochem also have business in the area of concrete admixtures, food and pharm, daily use that includes Water Reducer, Hydroxyethyl Cellulose, Sodium Carboxymethyl Cellulose.

In the 1930s, it was found that after mixing sulfite pulp waste into concrete, the workability of the mix could be improved, and the strength and durability could also be improved. In 1935, E. W. Scripture in the United States first developed a water-reducing agent with linosulfonate as the main component, and obtained a patent in 1937. In the 1950s, it was widely used in the United States slip form concrete, dam concrete and winter construction concrete. In 1962, Hattori Ken, first of all, of the Japanese Kawang alkali Company, first developed a water reducer with R mononaphthalene sulfonate formaldehyde condensation sodium salt as the main component, referred to as naphthalene series water reducer. This type of water reducer has the characteristics of high water reduction rate, and is suitable for preparing high strength (compressive strength up to 100MPa) or slump up to 20 (2) concrete. Subsequently, in 1964, the Federal Germany successfully studied sulfonated melamine formaldehyde resin superplasticizers, which also had the characteristics of high water reduction rate, good early strength effect and low gas intake with naphthalene series superplasticizers. At the same time, it had good adaptability to steamed concrete products and cement products with high content of aluminate (mainly C3A), and could prepare high-strength or high-fluidity concrete. Germany thus invented the fluid concrete, so that concrete from the original manual pouring or hanging pot pouring development to pumping construction, saving manpower, improve efficiency, ensure quality, eliminate noise, so that the technical level of concrete and construction level has a great leap. Due to the important contribution of high efficiency water reducing agent to concrete modification, its application has become the third major breakthrough in the history of concrete development after reinforced concrete and prestressed concrete. Marked by the development and application of high efficiency water reducing agent, concrete technology has entered the third generation from plasticity, dry hardening to fluidization. In the early 1990s, the United States first proposed the concept of high performance concrete (HPC), that is, the concrete is required to have high strength, high fluidity, high durability and other properties, high performance concrete put forward higher requirements for water reducer, requiring high performance water reducer with high water reduction rate, large flow and slump loss. Some new superplasticizers have been rapidly developed and applied, such as polycarboxylic acid series, sulfamic acid series superplasticizers. China's admixtures started later than foreign countries, but developed rapidly. In the 1950s, the research and application of lignosulfonate and air entraining agents began. After the 1970s, naphthalene series superplasticizer, onion series superplasticizer and other products have been independently developed; In the late 1990s, modified melamine, sulfamate, aliphatic superplasticizer developed rapidly; Since 2006, driven by the construction of high-speed railways, polycarboxylic acid series high-performance water reducing agents have also achieved rapid development. Superplasticizer has promoted the development of new concrete technology in China, promoted the application of industrial by-products in the cementing material system, and has gradually become an essential material for high-quality concrete. According to the chemical composition, it is usually divided into: lignosulfonate superplasticizer, naphthalene superplasticizer, melamine superplasticizer, sulfamate superplasticizer, fatty acid superplasticizer, polycarboxylate superplasticizer.