Property And Application
Gypsum board blowing agentk (also called a gypsum foaming agent) is a specialized surfactant system used in the manufacture of gypsum plasterboard to generate stable, fine foam within the gypsum slurry. The controlled introduction of air reduces board density while maintaining or even improving mechanical strength.
Working Principle
Foam Generation
During production:
- The foaming agent is diluted with water.
- Air is mechanically introduced into the solution.
- The surfactant lowers surface tension and disperses air uniformly.
- An electric double layer forms on the liquid film surface.
- Air bubbles are wrapped and stabilized, creating fine, dense, and uniform foam.
This maximizes the contact surface between liquid and gas, ensuring stable bubble formation.
Interaction with Gypsum
When the foam is mixed with gypsum slurry (calcium sulfate hemihydrate):
- The foaming agent interacts with hydrated gypsum particles.
- Hydrogen bonding and intermolecular forces form temporary chain-like structures.
- Steric hindrance occurs, limiting excessive crystal growth.
- The gypsum lattice structure becomes more controlled and refined.
- Gypsum activity is stimulated.
- A network-like gypsum skeleton forms more rapidly.
This controlled crystallization enhances structural integrity.
Resulting Benefits in Gypsum Board
✔ Enhances strength-to-weight ratio
✔ Reduces board density (lower bulk capacity)
✔ Saves raw materials (less gypsum consumption)
✔ Improves uniformity of internal structure
✔ Enhances physical properties such as:
Bending strength
Nail-holding capacity
Dimensional stability
Thermal insulation performance
Industrial Significance
By introducing stable micro-foam into the gypsum matrix:
- The board becomes lighter without sacrificing strength.
- Production efficiency improves.
- Transportation and installation costs are reduced.
- Overall material utilization is optimized.
Key Technical Requirements of a Good Gypsum Foaming Agent
- Strong foaming ability
- Fine and uniform bubble size
- High foam stability
- Good compatibility with gypsum slurry
- Controlled setting interaction
- No negative impact on board surface quality
Specs
|
ITEM |
STANDARD |
|
Appearance |
Light yellow transparent liquid |
|
Active material % |
≥34 |
|
Petroleum ether soluble content % |
≥1.8 |
|
Sodium sulfate content % |
≤2.0 |
|
Sodium chloride content % |
≤0.1 |
|
PH (1%water solution) |
7-9.5 |
|
Klett |
≤60 |
|
Foam height(mm)(5%active substance) |
≥180 |
|
Foam drop height after 5 minutes (mm) |
≤5 |
