With the development of modern ceramic technology, people have put forward higher requirements for the performance of ceramics. Sodium tripolyphosphate is an additive commonly used in architectural sanitary ceramics. Because of its small amount of addition and excellent role, it is known as monosodium glutamate in the ceramic industry. As a ceramic diluent, it is playing an increasingly important role in ceramic production.
Sodium tripolyphosphate diluent, also known as water reducer, adhesive agent and decoagulant, is mainly used to improve the fluidity of building sanitary ceramic billets and glaze slurry, so that their slurry has less moisture, better fluidity, no flocculation and precipitation, and is easy to operate. At the same time, the reasonable selection of diluents can also save energy consumption and reduce production costs for ceramic enterprises.
The system formed after the dispersion of solid particles in liquid media should belong to the category of colloids. The system is thermodynamically unstable and the particles tend to agglominate.
Sodium tripolyphosphate can cooperate with divalent ions such as calcium and magnesium in ceramic mud to form soluble complexes. This complexation replaces calcium and magnesium ions, thus reducing the impact of these ions on the interaction between ceramic particles.
At the same time, sodium tripolyphosphate introduces more sodium ions into the system through cation exchange. These sodium ions surround clay particles, forming a layer of charge, thus changing the surface charge properties of clay particles.
3) Spatial potential resistance effect
The introduction of sodium ions increases the distance between clay particles and reduces their mutual attraction. At the same time, due to the hydration between sodium ions and water molecules, the spatial potential resistance between particles is further increased, making it more difficult for particles to aggregate.
The molecule of sodium tripolyphosphate can be adsorbed on the surface of ceramic particles and destroy the flocculation between the particles through the interaction of adsorption. This adsorption allows the particle surface to form a protective film and reduces the interaction between the particles.
5) Improve the performance of slurry
Through the above mechanism, sodium tripolyphosphate improves the properties of ceramic slurry. This allows the slurry to maintain good fluidity at a low moisture content, and improves the dispersion and stability of the slurry. This is conducive to the molding and firing process of ceramic products, and improves the quality and production efficiency of products.
Some solid particles that are insoluble in water or slightly soluble in water can be evenly dispersed in liquid media with the help of sodium tripolyphosphate, forming a small high-suspension and flowing stable liquid solid system, which plays a role in improving the suspension stability of the slurry. This suspension stabilization mechanism of sodium tripolyphosphate is actually similar to its dispersion mechanism. Suspension stability can be achieved by improving the dispersion of ceramic particles in liquid media. However, the dispersant is mainly used in the slurry, while the suspension stabilizer is mainly used in the glaze slurry, which has a thickening effect on the glaze slurry and is an additive to prevent the precipitation of the glaze slurry.
3. Water reduction effect
The water reduction effect of sodium tripolyphosphate is to improve the performance of the slurry, so that the slurry has appropriate viscosity, good fluidity and high solid phase content under low moisture conditions, so as to facilitate operation and achieve the purpose of energy conservation and consumption reduction.
1. Improve the fluidity of slurry:
As a water reducer, sodium tripolyphosphate can improve the fluidity of ceramic billet and glaze slurry in ceramic production, so that its slurry has the least moisture, better fluidity, no flocculation and precipitation, and easy operation.
By complexing divalent ions such as calcium and magnesium in clay mud, sodium tripolyphosphate surrounds more sodium ions around the clay, reducing the mutual attraction between particles and thus improving the fluidity of the slurry.
2. Reduce the moisture content of mud:
Sodium tripolyphosphate can reduce the moisture content of mud, prevent shrinkage and deformation cracking when the billet is drying, and reduce the breakage rate of the billet.
This means that more slurry can be treated during the same production time, because the mud has good fluidity and low moisture content, which improves production efficiency.
The system formed by the dispersion of clay particles in the liquid medium belongs to the colloid. The system is very thermodynamically unstable. The particles will attract each other and then agglominate. Ceramic additives prevent each other by acting on the surface of ceramic particles from agglomeration, which can prevent particle agglomeration.
Sodium tripolyphosphate can react with oxides in ceramic powders to form phosphate compounds.
These phosphate compounds can increase the adhesion between ceramic particles, thus improving the adhesion strength of ceramics.
At the same time, the filling of sodium tripolyphosphate can reduce the pores in the ceramics and further improve the density and hardness of the ceramics.
2) Bridge between particles:
Between ceramic particles, sodium tripolyphosphate can form an irregular mesh structure and act as a bridge. This kind of bridging can greatly enhance the strength of ceramic products.
3) Hydrogen bond formation:
The addition of sodium tripolyphosphate can also produce hydrogen bonds on the surface of ceramic particles, which can further enhance the binding force between particles.
4.) Improve the dispersion of raw materials:
Sodium tripolyphosphate has a dispersion effect and can prevent particle agglomeration in ceramic raw materials.
The uniform dispersion of raw materials can ensure the uniformity and stability of ceramic products, thus improving their overall strength.
5) Water reduction and stabilization:
Sodium tripolyphosphate can improve the performance of ceramic slurry, giving it appropriate viscosity and good fluidity under low moisture conditions.
This improvement can reduce cracking and deformation during the molding process, thus improving the quality of ceramic products.
6) Improve alkali corrosion resistance:
The reaction of sodium tripolyphosphate with alkali metal oxides in ceramics can form stable compounds.
These compounds can improve the chemical stability between ceramic materials and
ACID and alkali media, thus enhancing their alkali corrosion resistance.
By enhancing the mechanism, sodium tripolyphosphate, as a ceramic additive, can effectively improve the quality and performance of ceramic products. In practical application, it is necessary to select the appropriate amount and addition method of sodium tripolyphosphate according to the specific ceramic products and production process to achieve the best enhancement effect.
