Ultem®: high-performance thermoplastic resin

Ultem® is the registered trademark of Sabic, one of the world’s leading producers of high-performance plastics, under which polyetherimide (PEI) is sold. It is a high-performance thermoplastic resin belonging to the family of high-temperature polymers.

This material stands out for its high heat resistance as well as excellent mechanical properties, chemical resistance and dielectric performance. It also has low moisture absorption and high radiation resistance. Polyetherimide offers high wear resistance and a low coefficient of friction, which contributes to the durability and reliability of components even under harsh operating conditions.

It is used in a wide range of industrial applications that require reliable materials, able to keep their functional, mechanical and electrical properties over time even in critical operating conditions, ensuring high performance and long service life.

These characteristics, together with its optical transparency, make Ultem a reference material for many sectors such as automotive, railway, boating and marine, hydraulic fittings, medical, lighting and manufacturing. Let us look in detail at the features of this resin.

Main properties of Ultem

Heat resistance

It keeps its mechanical properties up to 200 °C in continuous service, making it ideal for applications that require prolonged exposure to high temperatures.

Mechanical and tribological properties (wear and friction resistance)

It offers a good balance between stiffness and mechanical strength, ensuring high performance even in difficult operating conditions. In particular, it has:

• high stiffness
• high tensile strength
• good impact resistance and the ability to absorb repeated stress, preserving structural integrity over time
• high wear resistance and a low coefficient of friction, qualities that make it ideal for components subject to continuous movement or prolonged mechanical stress

Chemical and corrosion resistance

It offers excellent resistance to many chemicals and to corrosion, making it ideal for aggressive environments, including:

• oils and greases
• organic solvents
• weak acids and bases
• weathering agents such as humidity and climate changes

Dielectric properties

Thanks to its high insulating capacity, it is widely used in electronics and energy, where resistance to high voltages without degradation of the material is required. Some applications include:

• printed circuit board components
• high-voltage insulators
• electrical connectors and transformer supports

Radiation resistance

Thanks to its excellent stability to gamma rays and UV rays, it is used in applications that require resistance to this radiation, such as in the aerospace and medical sectors.

Low moisture absorption

Unlike many other high-performance polymers, it has low moisture absorption, keeping its mechanical and electrical properties unchanged even in highly humid environments.

Fire resistance

It is a self-extinguishing material, certified to UL 94 V-0, which prevents flame from spreading and ensures rapid extinction once the source of fire is removed. This makes it particularly suitable for applications where fire safety is essential, such as in the railway, aerospace and electronics sectors.

Dimensional stability and durability

It has good dimensional stability and high durability even under thermal and mechanical stress, keeping its mechanical and chemical properties unchanged. These characteristics make it an ideal material for applications that require precision and consistent reliability over time.

Optical transparency

It is available in several colours, including a transparent version that combines high optical transparency with the strength and durability typical of the material.

Biocompatibility and resistance to sterilisation

It is biocompatible and can be sterilised without losing its mechanical and chemical properties. These characteristics make it ideal for reusable medical devices, diagnostic components and other healthcare applications.

Good processability and versatility in production processes

It adapts well to many processing methods, including injection moulding. This versatility allows efficient and flexible production, even for components with complex geometries or strict technical requirements.

Applications of Ultem in different industrial sectors

Automotive

In the automotive sector, Ultem is used to produce components exposed to high temperatures, continuous mechanical stress and critical environments. Thanks to its heat resistance, dimensional stability and self-extinguishing behaviour, it is a valid alternative to metals and other engineering polymers, reducing weight and increasing durability. The main applications include:

• engine parts and components for cooling systems, where heat and corrosion resistance are required
• electrical connectors and sensors, exposed to vibration, thermal stress and aggressive environments
• lightweight structural components, combining stiffness and strength to reduce the overall weight of the vehicle

Railway

Thanks to its fire resistance and dimensional stability even at high temperatures, Ultem is widely used in the railway sector for components that require high performance in terms of safety and durability. It is used for:

• electrical insulators and connectors, resistant to thermal stress and critical environments
• railway interior components, where high heat resistance and self-extinguishing behaviour are required
• structural parts for carriages that are light, stable and durable even in extreme operating conditions

Boating and marine

In the boating and marine sector, Ultem is valued for its mechanical strength, stability in corrosive environments and long-term durability, even in the presence of humidity, salt and dynamic stress.

Thanks to its chemical resistance, low moisture absorption and high stiffness, it is used in many technical applications, including:

• hydraulic fittings and valves for cooling circuits exposed to sea water
• structural components subject to mechanical stress and abrasion
• technical parts for high-performance boats

Hydraulic fittings

Thanks to its high chemical and mechanical resistance, Ultem is particularly suitable for valves and hydraulic fittings designed to operate in critical conditions. It is used for:

• components operating at high temperature, where structural stability over time is required
• industrial plants in contact with solvents, acids and other aggressive chemicals, which require materials resistant to corrosion and hydrolysis

Parapharmaceutical and medical

The combination of biocompatibility, resistance to sterilisation processes and chemical resistance makes Ultem ideal for medical and diagnostic applications. It is used for:

• reusable surgical instruments, sterilised repeatedly without degradation of the material
• components for imaging and diagnostic equipment, where dimensional precision and resistance to solvents and detergents are required
• drug delivery devices

Lighting

Thanks to its optical transparency and heat resistance, Ultem is used in the lighting sector for applications that require materials that remain stable even at high temperatures. It is used for:

• high-performance reflectors and LED lamp components
• printed circuit board supports used in lamps operating at high temperatures

Manufacturing

In the manufacturing industry, Ultem is used to produce high-performance technical components, thanks to its thermal and mechanical stability, wear resistance and long-term durability.

It is particularly suitable in production environments where light and rigid materials are required. It is used for:

• structural and functional components operating at high temperatures or under repeated loads
• supports and insulating elements for advanced industrial processes and automation
• light and strong structures for high-precision machinery

Ultem compared with other high-performance plastics

In complex industrial applications, it is useful to compare the technical properties of Ultem with those of other commonly used high-performance engineering polymers in order to select the most suitable material.

The table below compares the most relevant characteristics, including heat resistance, dimensional stability, chemical resistance, dielectric properties and optical transparency.

Key

• The numerical scale from 1 to 5 indicates the level of performance, where:
  • 1 = Low
  • 2 = Fair
  • 3 = Medium
  • 4 = High
  • 5 = Excellent
• The “Optical transparency” column refers to whether the material is available in a transparent version. A high score indicates greater available optical transparency.
• The values given are indicative and may vary depending on the material grade, the presence of additives and the conditions of use.

Pioneers in Ultem processing

Corti Srl was one of the first companies in Italy to introduce and process Ultem in an innovative way, recognising from the outset its potential as a high-performance thermoplastic resin.

In 1997, GE Plastics Italia – now part of the Sabic Innovative Plastics business unit of the Sabic petrochemical group – presented us with the “Protagonists of the future” award, recognising us as pioneers in the industrial processing of Ultem.

An achievement that reflects our decades of experience in processing high-performance materials for technical and specialised sectors.

Conclusion

Ultem is a thermoplastic resin with unique characteristics, able to ensure high performance, long-term reliability and resistance in critical conditions. Its versatility makes it a valuable resource for modern industry.

If you are looking for custom Ultem solutions or want to explore the potential of this resin for your project, contact us for dedicated technical advice. We are ready to support you with the most advanced moulding and processing technologies.