The LE-9229/LH-9229 epoxy resin system is a dual-component, modified rubber-toughened formulation
designed for demanding electrical insulation applications.
Combining LE-9229 epoxy resin and LH-9229 hardener at a precise 1:1
ratio (100 pbw each) with silica flour filler (280-340 pbw), this
system delivers exceptional thermal stability (Tg 105-125°C), crack
resistance, and mechanical strength. Ideal for medium/high-voltage
insulation (10-35kV), it supports both automatic pressure gelation
(APG) and vacuum casting processes, making it suitable for
transformers, solid-pole bushings, and switchgear components.
Key Features & Advantages
Ultra-High Thermal Resistance:
Glass transition temperature (Tg): 105-125°C
Thermal decomposition: >320°C
Low water absorption: 0.08-0.20% (23°C to 100°C)
Superior Electrical Insulation:
Volume resistivity: 10¹⁵ Ω·cm
Dielectric strength: 30 kV/mm
Loss factor: 0.02
Robust Mechanical Properties:
Tensile strength: 65-95 MPa
Flexural strength: 110-150 MPa
Impact resistance: 10-18 kJ/m²
Process Flexibility:
Optimized for APG injection (10-30 min gelation) and vacuum casting
(3-6 hr cure).
Low curing shrinkage (0.7-0.9%) ensures dimensional stability.
Technical Parameters
Component Properties
| Epoxy Resin LE-9229 | Hardener LH-9229 |
|---|
| Appearance: Milky white, viscous liquid | Appearance: Pale yellow liquid |
| Viscosity at 25°C: 10.5-16.5 Pa.s | Viscosity at 25°C: 400-800 mPa.s |
| Density: 1.16-1.20 g/cm³ | Density: 1.17-1.24 g/cm³ |
| Flash Point: ~135°C | Flash Point: ~140°C |
Cured System Performance
| Mechanical | Value | Electrical/Thermal | Value |
|---|
| Tensile Strength | 65-95 MPa | Volume Resistivity | 10¹⁵ Ω·cm |
| Flexural Strength | 110-150 MPa | Dielectric Strength | 30 kV/mm |
| Compressive Strength | 130-190 MPa | Thermal Conductivity | 0.8-0.9 W/m·K |
| Impact Strength | 10-18 kJ/m² | Loss Factor | 0.02 |
Processing Guidelines
| APG Injection | Vacuum Casting |
|---|
| Mix Temp: 40°C (1-2 hrs) | Mix Temp: 60°C (1-2 hrs) |
| Mold Temp: 130-150°C | Mold Temp: 80-100°C |
| Gel Time: 10-30 mins | Cure Time: 3-6 hrs |
| Post-Cure: 130-140°C × 6-10 hrs | Post-Cure: 130-140°C × 6-10 hrs |
Frequently Asked Questions (FAQ)
Q1: What filler is recommended for LE-9229?
A: Use 400-mesh silica flour at 280-340 pbw to enhance mechanical
strength and thermal conductivity.
Q2: Can LE-9229 withstand high-voltage environments?
A: Yes, its dielectric strength (30 kV/mm) and volume resistivity
(10¹⁵ Ω·cm) make it ideal for 10-35kV insulation.
Q3: How does APG differ from vacuum casting?
A: APG uses pressure (0.5-5 bar) for rapid production (10-30 min
gelation). Vacuum casting eliminates bubbles for precision parts
but requires longer curing (3-6 hrs).
Q4: Is this system flame-resistant?
A: Yes, rated HB (4mm) and V1 (12mm) under flammability tests.
