Sodium silicate binders are the main ingredients

Sodium silicate is a soluble alkali metal silicate material composed of alkali metal oxides and silica, which is a key component in sodium water glass binders. Its chemical formula is usually $Na_ {2} O · nSiO_ {2} $, $n $, which is called the silica-oxygen ratio, which has a great influence on the performance of sodium water glass. If the value of $n $is high, the bonding force of sodium silicate is strong, but the solubility is poor; if the value of $n $is low, the solubility is good, but the bonding force is weak.

Water is also an important component of sodium water glass binders. Water is used in it, one is to dissolve sodium silicate to form a uniform solution, so that the binder has good fluidity and maneuverability, which is convenient for construction and application; the other is to participate in the chemical reaction of the binder curing process, which also affects the curing speed and final performance of the binder. Appropriate amount of water can ensure that the binder forms a dense structure after curing, and then obtains good bonding strength and other properties.

In addition, in practical applications, in order to improve some properties of the sodium water glass binder, such as increasing its strength, improving collapse, adjusting the curing rate, etc., some modifiers are often added. Such as certain metal oxides, organic compounds, etc. Although these additives are not the main components, they play an indispensable role in optimizing the performance of sodium water glass binders.

What are the characteristics of Sodium silicate binders?

Sodium water glass binder, its performance characteristics are very important. Sodium water glass binder has the characteristics of strong bonding force. It can form a strong connection between the sand grains, so that the molding sand or core sand can maintain the predetermined shape, just like the beams and columns of the house, supporting the overall structure. When the mold or core is formed, it relies on this bonding force to stabilize the shape and is not easy to collapse.

Furthermore, the hardening speed can be adjusted. According to different casting needs, the hardening process can be adjusted by adding suitable hardening agents, etc. If rapid prototyping is required, the hardening can be accelerated; if more operation time is required, the hardening can be delayed. For example, the craftsman can adjust the solidification time of the material according to the urgency of the process.

And its fire resistance is good. Under the high temperature environment of casting, it can withstand hot topics and not easily soften and deform. Just like in high temperature flames, it can still stick to its shape, ensuring that the mold or core is stable and not damaged during high temperature molten iron casting, laying the foundation for the molding of castings.

In addition, the cost of sodium water glass binder is relatively low, and the sources are relatively wide. In this way, in large-scale casting production, it can effectively control costs and improve economic benefits, just like using plain materials to make excellent tools, which meets the needs of the foundry industry to balance costs and benefits.

At the same time, it also has certain environmental advantages. Compared with some other binders, sodium water glass produces fewer harmful substances during use, and causes relatively little pollution to the environment. This is in line with the current emphasis on environmental protection, such as upholding the green concept and performing casting to achieve the purpose of sustainable development.

Sodium silicate binders for which areas

Sodium water glass binder has a wide range of uses and is useful in many fields.

In the field of casting, its work is great. It can be used as a molding sand binder, with sand as the bone and sodium water glass as the network, the two are combined to make the molding sand obtain good strength and collapse. When the casting is formed, it can maintain the shape of the molding sand and resist the erosion and heat of molten iron; when it is cast, it is easy to collapse, making the casting sand cleaning convenient, so it is indispensable in the casting industry.

Construction also develops its strengths. It can be used to prepare waterproofing agents, apply them to building surfaces, or seep into building materials. It reacts with carbon dioxide in the air to form silicic acid gels, fill pores, and increase the waterproof and impermeability of buildings. It can also enhance the strength of the soil. When treating the foundation, soda water glass and calcium chloride solution are alternately injected into the soil, and the two react to form calcium silicate gels, strengthening the soil and improving the bearing capacity of the foundation.

Textile printing and dyeing industry, also see its shadow. It can be used as a bleaching aid, in the fabric bleaching process, it can help remove impurities on the fabric, such as wax, pectin, etc., and has a buffering effect. It stabilizes the pH value of the bleaching solution, ensures the uniform bleaching effect, and improves the whiteness and wettability of the fabric. In the printing process, it can be used as a thickening agent to control the rheological properties of the color paste, so that the printing pattern is clear and the boundary is regular.

In the chemical field, it is also widely used. Can participate in the preparation of molecular sieves, silica and other chemical products. When preparing molecular sieves, sodium water glass is used as a silicon source. After a series of reactions and treatments with aluminum sources and other additives, molecular sieves with specific pore structures and properties are obtained, which are widely used in catalysis, adsorption and separation. When making silica, sodium water glass can be acidified, precipitated and other steps to obtain highly dispersible silica, which is an important strengthening agent for rubber, plastics and other industries.

In summary, sodium water glass binders play a key role in casting, construction, textile printing and dyeing, chemical industry and other fields. They are actually important materials with a wide range of functions.

Sodium silicate binders in the use of what are the precautions

During the use of sodium water glass binder, many matters need to be paid attention to.

First, the proportion should be accurately controlled during modulation. The modulus and density of water glass have a great impact on its performance. If the modulus is too high, although the strength is good, the hardening speed is too fast, and the molding is not easy; if the modulus is too low, the strength is insufficient. If the density is too high, the fluidity is poor, and it is difficult to distribute evenly; if the density is too low, the bonding force is not good. Therefore, it needs to be precisely prepared according to the specific application and process requirements.

Second, the hardening conditions need to be suitable. Sodium water glass is often hardened by carbon dioxide gas or hardened by natural drying. When hardening by carbon dioxide, the ventilation time and pressure need to be reasonably controlled. If the ventilation is too short, the hardening is not sufficient, and the strength is difficult to meet the standard; if the ventilation is too long, the surface is easy to carbonize, which affects the internal performance. Natural drying and hardening should pay attention to the ambient temperature and humidity. If the temperature is too low and the humidity is too high, the hardening is slow, and it may even cause the binder to deteriorate.

Third, pay attention to the preservation method. It should be placed in a cool and dry place to avoid direct sunlight and moisture. Because it is easy to absorb moisture, it will cause modulus and density changes after moisture absorption, which will affect the performance. If it is not stored properly and deteriorates, such as precipitation, agglomeration, etc., it needs to be carefully checked and treated before use, and if necessary, redeployed.

Fourth, the construction operation should be standardized. Before use, ensure that the surface of the bonded object is clean, dry, When applying evenly, avoid local too thick or too thin. Do not disturb within the specified time after bonding to ensure firm bonding.

In short, the use of sodium water glass binder, from modulation, hardening, preservation to construction, all aspects need to be carefully operated to ensure that it can play a good bonding performance and meet the needs of the project.

Sodium silicate binders compared to other binders

Compared with other kinds of binders, the sodium water glass binder has three advantages.

The first is fire resistance. The sodium water glass binder can stabilize its shape under high temperature and is not easy to melt. If it is baked in a furnace with a hot flame, other kinds of binders may have softened and deformed, but the sodium water glass binder can still keep its structure intact, so that the utensils are not destroyed by high temperature. This is especially important in the production of refractory materials.

The second is the strength of the bond. It can form a strong bond with the surface of the adhesive, so that the parts are closely connected. From the perspective of the foundry industry, the sand mold relies on sodium water glass binder to consolidate, which is not easy to break when stressed, and can withstand the impact of molten metal casting to ensure the quality of castings. This strong adhesion is useful in many processes that need to be firmly combined.

Furthermore, its cost is quite low. The raw materials of sodium water glass are easy to obtain, and the preparation method is not complicated. Compared with the binders made from rare raw materials or complex processes, the cost is greatly reduced. In large-scale production, the cost reduction can increase the profits of enterprises, and also make the products more cost-effective in the market. Therefore, it can be widely used in construction, foundry and other industries. Therefore, sodium-water glass binders are important in various industrial fields due to their fire resistance, strong bonding, and low cost.