E57-89H Eco-Friendly High-Temperature Resistant Flame-Retardant Polyester Insulating Resin Insulating Varnish
Product Applications:
E57-89H is a one-component Class H heat-resistant polyester insulating resin designed for vacuum and atmospheric-pressure impregnation of electrical equipment. It is formulated from modified high-temperature-resistant unsaturated polyester resin, flame-retardant resin, reactive diluents, stabilizers, and performance additives.
E57-89H offers low odor, low VOC emissions during baking, strong adhesion, excellent penetration, reliable electrical insulation performance, high mechanical strength, and good resistance to moisture and mildew. It cures rapidly during baking and provides excellent compatibility with commonly used insulation materials.
The resin is compatible with DuPont Nomex paper and Quin-T TufQuin paper. It remains non-tacky when hot, is compatible with magnet wire, and does not react with bare copper wire, helping prevent verdigris and copper corrosion. E57-89H also provides excellent resistance to thermal shock across high- and low-temperature conditions and is easy to process.
E57-89H is widely used for the impregnation insulation treatment of Class B, F, and H dry-type power transformers, reactors, new energy vehicle motors, large generators, crane motors, variable-frequency motors, refrigerant-resistant motors, and related electrical equipment.
- Description
- Technical Data
- FAQ
Description
Product Features:
· Modified high-temperature resistant unsaturated polyester resin, thermal class: Class H (above 180°C)
· Strong adhesion: effectively reduces electromagnetic vibration and electrical noise of coils, with rapid curing.
· Adjusts the coefficient of thermal expansion between metal and insulation with temperature changes, reducing damage to coils caused by thermal expansion.
· Excellent high and low temperature resistance (-40°C to 180°C), with certain flexibility of the film.
· Compliant with EU RoHS and REACH, halogen-free and eco-friendly.
Physical Properties：
The following items refer to the test methods of GB/T 15022.2-2017:
| Item | Test Condition | Specification |
| Appearance | Test tube method, visual | Light yellow transparent liquid, free of mechanical impurities |
| Viscosity | Tu-4 Cup, 25±1℃ | 50-200″ |
| Curing Time | 135℃~145℃ | ≥4h |
| Thick-Layer Curing Ability | 10 g of resin in a 45×45×25mm aluminum box, 135℃3h | Not inferior to S1-U1-I2.2, uniform |
| Storage Viscosity Growth Coefficient | 60℃ constant temperature / 96h, closed-cup method | <20% |
| Electric Strength | Normal state | ≥22MV/m |
| 20℃±5℃ water immersion for 24h | ≥22MV/m | |
| Softening Breakdown Temperature (for enameled wire) | ≥280℃ | |
| Bond Strength | Normal state | ≥120N |
| 180℃±2℃ | ≥80N | |
| Volume Resistivity | Normal state | ≥1×1013Ω•cm |
| 20℃±5℃ water immersion for 7 days | ≥1×1012Ω•cm | |
| 180℃±2℃ | ≥1.2×109Ω•cm | |
| Thermal Conductivity | W/(m.K) | ≥0.4 |
| Oil Resistance | 180℃±2℃24h (engine oil BOT805CEV/BOT790/SL3767) | Paint film smooth and flat, free of bubbles and cracks |
| TGA Temperature Index | GBT27761-2011 | ≥265℃ |
| Thinner | X-101 | |
Application Method：
· Vacuum Process: Place the stator into the varnish tank; first inject the varnish into the tank under negative pressure until the vacuum reaches 0.08, or hold the pressure and immerse for 30 minutes; remove the workpiece from the tank and drip-dry for >30 minutes; raise the temperature to 135℃ and bake Baking3-6hours or until motor resistance value stabilizes.
· Trickle impregnation process: Preheat the workpiece to about 50℃ before starting trickle impregnation for better results.
· During vacuum impregnation, pressure impregnation/exhausting, and the baking of impregnated workpieces, ventilation and exhaust ducts with organized discharge must be provided.
The specific baking time should be determined through experiments according to the shape and size of the workpiece, equipment conditions and curing degree requirements, so as to determine the baking temperature and time suitable for the product.
Precautions:
· Determine the dilution ratio, baking temperature, and baking time experimentally based on product shape, size, and specific requirements. Recommended baking temperature: do not exceed 100°C.
· The product may absorb moisture and turn whitish under high humidity; performance remains unaffected after baking.
· This product is flammable; keep away from fire and heat sources.
Packaging, Storage/Transport & Shelf Life：
· Packaging: metal pails, 18 KG/pail
· Storage & transport: flammable chemical — keep away from fire and heat; handle per regulations; store cool (RT), dark and dry.
· Shelf life: stored sealed, 6 months at 5-25℃.
Frequently Asked Questions
What is the minimum order quantity (MOQ) for E57-89H?
The standard MOQ for E57-89H is 18 kg (one pail). For trial quantities below the standard MOQ, please contact us for sample availability and a customized quotation.
What packaging is available?
E57-89H is supplied in the following standard packaging:
- 18 kg per pail
Please contact us for bulk-order pricing, export packaging, or customized packaging requirements.
Can I request a sample before placing a bulk order?
Yes. Free samples of E57-89H are available for quality evaluation and application testing. Please contact us to confirm sample availability and quantity. The customer is responsible for shipping costs and related delivery charges.
What is E57-89H used for?
E57-89H is a single-component Class H high-temperature insulating resin for vacuum and atmospheric-pressure impregnation of electrical windings and insulation systems. It is widely used in dry-type power transformers, reactors, new energy vehicle motors, large generators, crane motors, variable-frequency motors, refrigerant-resistant motors, and other electrical equipment.
What are the main features of E57-89H?
E57-89H is a modified high-temperature unsaturated polyester insulating resin with low odor and low VOC emissions during baking. It provides strong adhesion, excellent penetration, reliable electrical insulation, high mechanical strength, rapid oven curing, and good moisture and mildew resistance.
The resin also offers excellent resistance to high- and low-temperature thermal shock. Its cured film retains a degree of flexibility, helping support reliable insulation performance in demanding electrical applications.
What is the thermal class of E57-89H?
E57-89H is a Class H high-temperature insulating resin, with a thermal class rating of above 180°C. It is designed for electrical insulation systems that require dependable heat resistance and long-term thermal performance.
What temperature range can E57-89H withstand?
E57-89H provides excellent high- and low-temperature resistance from −40°C to 180°C. Its cured film maintains a degree of flexibility, helping the insulation system withstand temperature changes and thermal cycling.
Is E57-89H suitable for transformer and motor impregnation?
Yes. E57-89H is suitable for vacuum and atmospheric-pressure impregnation insulation treatment of Class B, F, and H dry-type power transformers, reactors, motors, generators, coils, windings, and compatible electrical equipment.
Is E57-89H a single-component insulating resin?
Yes. E57-89H is a single-component insulating resin, making it convenient to handle and use in electrical impregnation processes. Please follow the verified application instructions in the Technical Data Sheet (TDS).
Does E57-89H require baking or heat curing?
Yes. E57-89H is designed for oven-baking applications and cures rapidly during baking. Recommended curing temperature and curing time should be confirmed according to the product TDS and your actual production process.
What are the recommended impregnation and curing parameters?
The recommended impregnation method, resin viscosity, impregnation time, draining time, baking temperature, and baking time should be confirmed based on your equipment, component structure, and production requirements. Please refer to the Technical Data Sheet (TDS) or contact our technical team for verified application guidance.
How does E57-89H help reduce coil vibration and electrical noise?
E57-89H provides strong adhesion between windings, conductors, and insulation materials. After curing, it helps stabilize the coil structure, reducing electromagnetic vibration and associated electrical noise.
How does E57-89H help protect coils during temperature changes?
The cured E57-89H resin film helps accommodate differences in thermal expansion between metal conductors and insulation materials. This helps reduce internal stress caused by heating and cooling cycles and lowers the risk of coil damage.
Is E57-89H compatible with electrical insulation materials?
E57-89H demonstrates good compatibility with DuPont™ Nomex® paper, Quin-T TufQuin® paper, and magnet wire. Compatibility testing is still recommended before mass production, especially when using new insulation-system materials or different processing conditions.
Is E57-89H compatible with bare copper wire?
Yes. E57-89H does not react with bare copper wire and helps prevent verdigris formation. It is also compatible with magnet wire and remains non-tacky when hot.
Does E57-89H have low odor and low VOC emissions?
Yes. E57-89H features low odor and low VOC emissions during baking, supporting a more user-friendly electrical insulation manufacturing process.
Is E57-89H resistant to moisture, mildew, and thermal shock?
Yes. E57-89H provides good moisture and mildew resistance, as well as excellent resistance to high- and low-temperature thermal shock. Its flexible cured film helps support durable insulation performance in demanding operating environments.
Is E57-89H RoHS and REACH compliant?
Yes. E57-89H complies with applicable EU RoHS and REACH requirements. Please contact us if you require compliance declarations, test reports, or other supporting documentation for your project.
Is E57-89H halogen-free?
Yes. E57-89H is a halogen-free insulating resin formulation, making it suitable for applications that require environmentally responsible electrical insulation materials.
What is the shelf life of E57-89H?
E57-89H has a shelf life of 6 months when stored in the original unopened container. Please check the product label or contact us for batch-specific information.
How should E57-89H be stored?
Store E57-89H in its original, unopened packaging and follow the storage and handling requirements provided in the Technical Data Sheet (TDS) and Safety Data Sheet (SDS). Please keep the container tightly sealed when not in use.
Can you provide technical and compliance documents?
Technical and quality documents may include the Technical Data Sheet (TDS), Safety Data Sheet (SDS), Certificate of Analysis (COA), RoHS documentation, REACH documentation, and halogen-free declarations. Please contact us to confirm the documents required for your project.
Do you provide technical support?
Yes. Our technical team can assist with product selection, impregnation-process evaluation, baking and curing-process optimization, material compatibility testing, and electrical insulation manufacturing requirements.