English
| Quantity: | |
|---|---|
XF-270; XF-B-1;
Product Introduction:
Polyester polyols are key functional materials used in controlled-release fertilizer (CRF) coatings because they allow precise tuning of nutrient release, mechanical strength, and biodegradability.
This specialized polyester polyol enables precise regulation of nutrient release kinetics in controlled-release fertilizers, ensuring sustained and efficient nutrient uptake by crops throughout their growth cycle. Additionally, customized coloration is achievable via the incorporation of tailored color powders or pigments.
Polyester polyols are mainly used as reactive components in polyurethane (PU) coatings applied to fertilizer granules (e.g., urea, NPK).
They help achieve:
Controlled nutrient release rate
Water resistance with controlled permeability
Good coating strength & adhesion
Potential biodegradability (depending on structure)
Polyester polyols react with isocyanates (MDI, TDI, PDI) to form polyurethane membranes.
Water penetrates slowly through the coating
Nutrients dissolve inside the granule
Nutrients diffuse out gradually
The polyester polyol structure directly controls diffusion speed.
Low MW (500–1000) → faster nutrient release
Medium MW (1000–3000) → balanced release
High MW (>3000) → slow, long-term release
Higher OH number → higher crosslink density → slower release
Typical OH value: 50–200 mg KOH/g
Common acids:
Adipic acid → flexible, good permeability control
Succinic / Sebacic acid → improved biodegradability
Phthalic / Isophthalic acid → increased rigidity, slower release
Common glycols:
Ethylene glycol (EG)
Diethylene glycol (DEG)
1,4-Butanediol (BDO)
Neopentyl glycol (NPG)
Polyester polyols influence:
Hydrophilicity / hydrophobicity
Coating density
Micro-porosity
Swelling behavior in soil moisture
By adjusting formulation, CRFs can be designed for:
30–45 days
60–90 days
120–180 days nutrient release
To meet environmental regulations, manufacturers increasingly use:
Aliphatic polyester polyols
Bio-based acids (succinic, sebacic)
Bio-based glycols
These allow:
Gradual coating degradation after nutrient release
Reduced microplastic accumulation in soil
| Specification | XF-270 | XF-B-1 |
| Appearance | Light yellow to brownish yellow transparent liquid | Light yellow to brownish yellow transparent liquid |
| Hydroxyl value，mgKOH/g | 260±10 | 300±30 |
| Acid value，mgKOH/g | 3±0.2 | ≤3.0 |
| Moisture content，% | ≤0.1 | ≤0.15 |
| Viscosity，mPa·s（25℃） | 3000±500 | 3000±500 |
| Uses | This product is a biodegradable resin, suitable for fertilizer coating. | This product is a biodegradable resin, suitable for fertilizer coating. |
| Packaging, storage and transportation | Packed in iron drums, net weight 200kg per drum. | Packed in iron drums, net weight 200kg per drum. |
This polyester polyol serves as a critical raw material in the manufacturing of diverse controlled-release fertilizer formulations, including urea-based controlled-release fertilizers, potash-based controlled-release fertilizers, and compound controlled-release fertilizers.
Product Introduction:
Polyester polyols are key functional materials used in controlled-release fertilizer (CRF) coatings because they allow precise tuning of nutrient release, mechanical strength, and biodegradability.
This specialized polyester polyol enables precise regulation of nutrient release kinetics in controlled-release fertilizers, ensuring sustained and efficient nutrient uptake by crops throughout their growth cycle. Additionally, customized coloration is achievable via the incorporation of tailored color powders or pigments.
Polyester polyols are mainly used as reactive components in polyurethane (PU) coatings applied to fertilizer granules (e.g., urea, NPK).
They help achieve:
Controlled nutrient release rate
Water resistance with controlled permeability
Good coating strength & adhesion
Potential biodegradability (depending on structure)
Polyester polyols react with isocyanates (MDI, TDI, PDI) to form polyurethane membranes.
Water penetrates slowly through the coating
Nutrients dissolve inside the granule
Nutrients diffuse out gradually
The polyester polyol structure directly controls diffusion speed.
Low MW (500–1000) → faster nutrient release
Medium MW (1000–3000) → balanced release
High MW (>3000) → slow, long-term release
Higher OH number → higher crosslink density → slower release
Typical OH value: 50–200 mg KOH/g
Common acids:
Adipic acid → flexible, good permeability control
Succinic / Sebacic acid → improved biodegradability
Phthalic / Isophthalic acid → increased rigidity, slower release
Common glycols:
Ethylene glycol (EG)
Diethylene glycol (DEG)
1,4-Butanediol (BDO)
Neopentyl glycol (NPG)
Polyester polyols influence:
Hydrophilicity / hydrophobicity
Coating density
Micro-porosity
Swelling behavior in soil moisture
By adjusting formulation, CRFs can be designed for:
30–45 days
60–90 days
120–180 days nutrient release
To meet environmental regulations, manufacturers increasingly use:
Aliphatic polyester polyols
Bio-based acids (succinic, sebacic)
Bio-based glycols
These allow:
Gradual coating degradation after nutrient release
Reduced microplastic accumulation in soil
| Specification | XF-270 | XF-B-1 |
| Appearance | Light yellow to brownish yellow transparent liquid | Light yellow to brownish yellow transparent liquid |
| Hydroxyl value，mgKOH/g | 260±10 | 300±30 |
| Acid value，mgKOH/g | 3±0.2 | ≤3.0 |
| Moisture content，% | ≤0.1 | ≤0.15 |
| Viscosity，mPa·s（25℃） | 3000±500 | 3000±500 |
| Uses | This product is a biodegradable resin, suitable for fertilizer coating. | This product is a biodegradable resin, suitable for fertilizer coating. |
| Packaging, storage and transportation | Packed in iron drums, net weight 200kg per drum. | Packed in iron drums, net weight 200kg per drum. |
This polyester polyol serves as a critical raw material in the manufacturing of diverse controlled-release fertilizer formulations, including urea-based controlled-release fertilizers, potash-based controlled-release fertilizers, and compound controlled-release fertilizers.
