Torlon® PAI

Get the Best of Both Worlds

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Torlon® PAI (polyamide-imide)combines the exceptional performance of thermoset polyimides with the melt-processing advantage of thermoplastics. Wear-resistance grades offer unsurpassed performance in both dry and lubricated environments. High-strength grades retain their toughness, high strength and high stiffness up to 275°C (525°F), making PAI the industry's highest performing thermoplastic. Its broad chemical resistance includes strong acids and most organics.

PAI exhibits greater compressive strength and higher impact resistance than most advanced engineering plastics. High creep resistance and an extremely low coefficient of linear thermal expansion (CLTE) provide excellent dimensional stability.

Comparison of Torlon® PAI grades

 Torlon-grades comparison

High-Temperature Wear Resistance

Wear-resistant grades Torlon® PAI offers and excellent combination of mechanical and tribological properties. This combines with excellent chemical resistance and high thermal stability to successfully replace metal in high-temperature friction and wear applications, even when lubrication is marginal or non-existent. Specially formulated grades can perform in lubricated environments at exceptionally high pressures and velocities (PV).



Torlon® 4275 grooved test specimen after 100 hours

Wear properties are enhanced by adding carbon fiber and polymeric lubricants such as PTFE. Torlon® PAI offers the best high-temperature wear resistance.

Torsional DMA of wear-resistant Spire® Ultra Polymers


Comparison of friction and wear grades


Specific Strength

High-strength grades of Torlon® PAI exhibit metal-like performance and are routinely specified for precision components used in repetitive-use, load-bearing operations. Glass-fiber and carbon-fiber-filled grades retain their strength and stiffness at high temperature with the added benefit of low creep and excellent fatigue resistance.

Specific tensile strength comparison of Torlon® PAI to metal

BarGraph_Tensile-strength_Torlon-vs-metalNew Component

Mechanical properties comparison of neat plastics [ASTM D790]


Compressive strength comparison of neat plastics [ASTM D695]


Toughness performance comparison


Coefficient of linear thermal expansion comparison

BarGraph_Torlon-CLTE-comparisonNew Component

Frequently Asked Questions

What is Torlon® PAI?

PAI is the acronym for polyamide-imide, a polymer that offers the highest strength and stiffness of any commercial thermoplastic at extremely high temperature and stress. Parts made of Torlon® PAI perform under conditions generally considered too severe for other thermoplastics. 
For this reason, critical mechanical and structural components for jet engines, automotive transmissions, oil recovery, off-road vehicles and heavy-duty equipment are manufactured from Torlon® PAI. 

What are the main advantages of Torlon® PAI?

Torlon® PAI offers the highest strength and stiffness of any thermoplastic up to 275°C (525°F). It has outstanding resistance to wear, creep, and chemicals – including strong acids and most organics – and is ideally suited for severe service environments. Other advantages include superior toughness at cryogenic temperatures, low coefficient of thermal expansion and outstanding resistance to aviation and automotive fluids.
More information: Torlon PAI Design Guide.

What makes Torlon® PAI different from other ultra-high temperature materials, such as polyimides?

Unlike other commercial thermoplastics, Torlon® PAI retains usable mechanical properties up to 275°C (525°F). Unlike polyimide, Torlon® PAI, is easier to process because it can be injection molded, which translates low unit cost for exactly replicated parts.

What products are included in the Torlon® PAI portfolio?

  • High-strength, unfilled grades 
  • High-strength, glass fiber and carbon fiber reinforced grades 
  • Wear-resistant grades for various PVs in dry and lubricated environments 
  • Specialty grades for undercut tooling, such as deep groove bearings
Torlon® PAI is also available in extrusion and compression molding grades, which are used to produce stock shapes for machining and low-volume production. 
A related line of Torlon® amide-imide (AI) powders, also available from Solvay Specialty Polymers, are used to manufacture high-temperature adhesives, non-stick coating primers, composite matrices, coatings and films.
More information: Torlon PAI Design Guide.

How can I obtain Material Safety Datasheets of Torlon® PAI grades?

Material Safety Datasheets can be obtained by contacting Specialty Polymers Representative.

I have heard that Torlon PAI is difficult to process ― is that true?

Torlon® PAI combines the mechanical and ultra-high temperature benefits of a polyimide with the significant advantage of being melt-processable like any standard polyamide. It is not difficult to process Torlon® PAI, as it can be molded in any standard injection molding machine. However, a very low compression screw is required and a few other modifications are necessary. In addition, a curing step is required to maximize both mechanical and chemical resistance properties. This curing step has to be managed with standard state-of-the-art ovens. 
Qualified Torlon® PAI processors are present in all regions of the world, and they demonstrate outstanding processing capabilities with world class yields and excellent quality. In order to maintain and ensure that the highest quality standards are met, we require that all Torlon® PAI molders become an “Approved Molder” via a Solvay qualification process.
If you need to locate an approved Torlon® PAI molder or if you like to become an approved molder, please contact your Solvay Specialty Polymers Technical Marketing Representative.
More information: Torlon PAI Processing Guide.

Where is Torlon® PAI produced?

Torlon® PAI base resins and compounds are produced in Solvay’s U.S. plant in Greenville, South Carolina, using state-of-the-art manufacturing technology. The high quality and reliability of Torlon® PAI products are well-established in numerous markets. 
More information: Spire Ultra Polymers.

Where can I get stock shapes for prototype development made from Torlon® PAI?

Quadrant Plastics and Drake Plastics are Solvay’s official and exclusive distributors of various sizes of plaques, rods, and tubes made from Torlon® PAI. Quadrant Plastics markets Torlon® PAI stock shapes under the Duratron® trade name.
Please contact your Specialty Polymers Technical Marketing representative to find the partner to best address your needs.

What about Torlon® PAI’s resistance to chemicals?

Torlon® PAI is virtually unaffected by aliphatic and aromatic hydrocarbons, chlorinated and fluorinated hydrocarbons, and most acids at moderate temperatures. However, the polymer, may be attacked by saturated steam, strong bases, and some high-temperature acid systems. Proper post-cure of Torlon® PAI parts is necessary to achieve optimal chemical resistance.
Please contact your Specialty Polymers Technical Marketing Representative for more information.
More information: Torlon PAI Design Guide.