Gypsum slowing agent is a additive specifically used to extend the time of gypsum condensation. Gypsum is mainly composed of gypsum and water. When the water is added to the gypsum, it will cause a chemical reaction and form a crystal structure. This process is indoctrinating, that is, it will generate heat. Crystal structure is the foundation of gypsum hardening and exerting its functions. Although this heat -reaction is critical to solidify the plaster, in some special applications, it also challenges the construction workers.
The problem comes from the reaction speed. In some construction conditions, especially when complex design and large -scale construction, fast solidification can cause uneven application and make the final effect unsatisfactory. The mud slowly condenser can slow down the condensation process and extend the construction time, thereby solving these problems.
The mechanism of plaster slowing agent is the dynamics of changing the process of gypsum crystal. First, when plaster and water are mixed, gypsum crystals begin to form. These crystals are part of gypsum matrix. Secondly, with the formation of more crystals, they will grow up and interlaced each other, so that the gypsum gradually solidifies. Gypsum slowing agent intervenes this process by inhibiting crystal growth. It is more difficult to bond and solidarize by interfere with the ability of crystal growth or change the surface characteristics of the crystal. Finally, as the growth rate of the crystal slows down, the solidification of gypsum will be delayed. Using gypsum slowing agent can make the construction workers accurately apply gypsum.
Gypsum retarder is a chemical additive used to control the setting speed of gypsum products. The following is a detailed introduction to gypsum retarder:
1. Definition and performance
Gypsum retarder is mainly used in gypsum building materials made of plaster gypsum, bonded gypsum, gypsum putty, gypsum products, etc. Its main function is to reduce the setting speed of gypsum. This additive is white, brown or off-white in powder form and is easily soluble in water.
2. Mechanism of action
Reduce the solubility and dissolution rate of hemihydrate gypsum.
Adsorb ions onto the surface of growing dihydrate gypsum crystals and bind them into the crystal lattice.
A complex is formed to limit the diffusion of ions to the vicinity of the dihydrate gypsum crystal.
3. Usage methods and precautions
Instructions:
The dosage in hemihydrate gypsum is usually 0.03%-0.5%. The specific dosage may vary due to factors such as the variety and performance of gypsum, temperature changes, etc.
You can mix the gypsum retarder and gypsum powder evenly, or dissolve the retarder in water first and then add it to the gypsum powder.
When used for plastering, mixing it with 0.5% cement can effectively extend the retarding time.
Precautions:
When adding gypsum retarder, it needs to be done in a specific proportion to avoid imbalance.
If the gypsum retarder appears to be solidified or sticky, it may have been contaminated or deteriorated and should be discontinued.
Before use, due to the different sintering quality and usage standards of gypsum powder in different places, strict tests should be done to determine the appropriate addition amount.
4. Application areas
Construction field: Gypsum retarder is mainly used in the production of gypsum products in the construction field, such as gypsum boards, gypsum blocks, etc. By controlling the setting time of gypsum, the plasticity and processing performance of gypsum products can be improved.
Decorative field: In the decorative field, gypsum retarder is mainly used in interior wall plastering and gypsum board production. Adding gypsum retarder can control the setting time and hardening speed of gypsum and improve construction performance and stability.
Medical field: In the medical field, plaster retarder is used to make plaster bandages. Adding a plaster retarder can prolong the setting time of the plaster, making the plaster bandage more flexible and comfortable, and is suitable for fracture fixation and limb orthopedic treatment.
In short, gypsum retarder plays an important role in the production and application of gypsum products. By rationally using gypsum retarder, the setting speed of gypsum can be controlled and the performance and quality of gypsum products can be improved.