Super absorbent polymer (SAP)
What is a super absorbent polymer indeed?
In agriculture, the superabsorbent polymer is also called water retaining polymer or soil condition agent.
It is a powerful water-absorbent material. The water absorption is hundreds of times of its weight.
1. Appearance
Before absorbing: White (or brownness) powder/granule.
After absorbing: Transparent gel.
2.Chemical component
The main chemical component of SAP is sodium polyacrylate or potassium polyacrylate.
- Sodium polyacrylate is produced by sodium hydroxide and acrylic acid;
- Potassium polyacrylate is produced by potassium hydroxide and acrylic acid.
3.Function
SAP can increase the water holding capacity of soil which is the meaning:
- The yield of crops/fruit trees will be increased;
- The water cost will be reduced;
- The fertilizer efficiency will be increased by reducing the loss to the underground.
Is super absorbent polymer good for the soil?
1.Potassium polyacrylate SAP
Potassium polyacrylate is totally good for soil:
- Before decomposed in the soil, it can keep increasing the water holding capacity of soil;
- After decomposed in the soil, potassium polyacrylate would break into potassium, water, carbon dioxide, etc.
2.Sodium polyacrylate SAP
In agriculture, sodium polyacrylate obviously is a bad choice.
After decomposed in the soil, sodium polyacrylate would be break into the water, carbon dioxide, and sodium which would cause soil alkalization.
Tips: As sodium polyacrylate is much cheap than potassium polyacrylate, profiteers would sell sodium polyacrylate instead of potassium polyacrylate.