Waterborne Polyester Resins
Paint chemicals 2025-03-21
Performance Features
High Gloss, Hardness, Anti-corrosion, Adhesion
Waterborne Polyester Resins: Overview and Key Properties
| Category | Details |
|---|---|
| Chemical Type | Carboxyl-functional polyester dispersion |
| Dispersion Medium | Water |
| Acid Value | 20-50 mg KOH/g |
| Key Feature | Sustainable alternative to solvent-borne systems |
Physical & Chemical Properties
| Property | Typical Value |
|---|---|
| Solid Content | 35-45% |
| Viscosity (25°C) | 100-1000 mPa·s |
| pH | 7.5-9.0 |
| Hydroxyl Value | 0-30 mg KOH/g |
| MFFT | 10-30°C |
Curing Systems
| Crosslinker | Cure Conditions | Features |
|---|---|---|
| Amino Resins | 140-160°C, 20-30 min | High hardness |
| Isocyanates | 60-80°C, 2-4 hrs | Flexible films |
| Epoxy Resins | 160-180°C, 15-25 min | Chemical resistance |
Applications
| Industry | Use Case | Key Benefit |
|---|---|---|
| Coil Coatings | Metal pre-coating | Formability |
| Wood Coatings | Furniture finishes | UV durability |
| Packaging | Food cans | FDA compliance |
| Automotive | Primer surfaces | Chip resistance |
Formulation Components
| Component | Function | Typical % |
|---|---|---|
| Resin Dispersion | Base polymer | 70-85% |
| Coalescent | Film formation | 3-8% |
| Defoamer | Process aid | 0.1-0.5% |
| Wetting Agent | Substrate adhesion | 0.5-2% |
Performance Advantages
| Feature | Comparative Benefit |
|---|---|
| VOC Content | <50 g/L vs 400-600 g/L (solvent) |
| Gloss | 85-95 at 60° |
| Adhesion | Class 0 (cross-cut test) |
Safety & Handling
| Parameter | Requirement |
|---|---|
| Flash Point | >100°C |
| Storage | 6-12 months @ 5-35°C |
| Freeze-Thaw | 3-5 cycles stable |
Market Data
| Segment | Market Share | Growth (CAGR) |
|---|---|---|
| Coil Coatings | 40% | 6.5% |
| Wood | 35% | 5.8% |
| Packaging | 25% | 7.2% |
Comparison with Solvent-borne
| Property | Waterborne | Solvent-borne |
|---|---|---|
| VOC | 90% lower | High |
| Cure Speed | 20% slower | Faster |
| Film Quality | Comparable | Slightly better flow |
Key Benefits and Limitations
| Advantages | Limitations |
|---|---|
| Excellent color retention | Higher cure temperatures |
| Good mechanical properties | Sensitive to pH changes |
| Easy water cleanup | Limited high-build capability |
Summary
Waterborne polyester resins offer eco-friendly solutions without compromising performance, particularly in coil and wood coating applications where color stability is critical.
