Ultem 2300 (30% Glass-Filled PEI): High-Stiffness Electrical & Aerospace Grade Thermoplastic

Ultem 2300 is the 30% glass-fiber-reinforced grade of polyetherimide (PEI), engineered to provide dramatically higher stiffness, lower thermal expansion, and improved dimensional stability compared to unfilled Ultem 1000. The glass fiber...

Ultem 2300 is the 30% glass-fiber-reinforced grade of polyetherimide (PEI), engineered to provide dramatically higher stiffness, lower thermal expansion, and improved dimensional stability compared to unfilled Ultem 1000. The glass fiber reinforcement increases flexural modulus by ~2.7× (9.0 GPa vs 3.3 GPa unfilled) and reduces mold shrinkage to 0.2-0.4% (vs 0.5-0.7% unfilled) — critical for tight-tolerance electrical connectors, circuit breaker housings, and avionics enclosures where post-molding warpage would cause misalignment.

Ultem 2300 is the dominant material for high-temperature electrical connectors and sockets in aerospace, military, and downhole oil-and-gas applications. It is inherently flame-retardant (UL 94 V-0 at 0.25 mm without flame-retardant additives — the polymer backbone contains aromatic imide groups that char rather than burn), has excellent dielectric properties stable across a wide frequency and temperature range, and withstands lead-free (RoHS) soldering processes (peak reflow temperatures 260°C for 30 seconds) that would melt or distort standard engineering thermoplastics (PBT, PA66, POM).

Processing requires high mold temperatures (135-165°C, oil-heated) and melt temperatures of 370-400°C. Drying is ESSENTIAL: PEI absorbs moisture rapidly from ambient air; processing undried PEI at 370°C causes hydrolysis (polymer chain scission) resulting in a 30-50% loss of tensile strength and elongation — parts shatter under load. Dry at 150°C for minimum 4 hours (desiccant dryer, -40°C dew point) to <0.02% moisture content.

Technical Properties

Equivalents & Cross-References

Related Diagnostics & Materials

References & Industry Standards

• ASTM International. Standard Specifications for Engineering Plastics & Thermoplastics. astm.org
• UL Prospector. Plastics & Elastomers Material Database. ulprospector.com
• MatWeb. Material Property Data for Engineering Thermoplastics. matweb.com
• ISO 1043. Plastics — Symbols and Abbreviated Terms. iso.org