High-Temperature Epoxy Resin System for Electrical Insulation APG & Vacuum Casting

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

Cured System Performance

Processing Guidelines

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.