The latest addition to Saint-Gobain’s Meldin^® family of materials, the 7000 series offers a powerful combination of performance characteristics that help it thrive in some of the most challenging applications on earth (and even in space). In this blog, we introduce the Meldin^® 7000 series, examine some of its most important features, and explain why it offers a more economical option than ever for applications calling for high-temperature polyimide performance.

What makes the Meldin^® 7000 series different?

Saint-Gobain’s Meldin^® family includes a broad range of materials, all backed by decades of engineering refinement and an impeccable quality control process (you can find specifications for TriStar’s full lineup of Meldin^® materials in our interactive material database here). The Meldin^® 7000 series brings a diverse lineup of thermoset polyimide materials into the Meldin^® family for the first time.

Just what makes Meldin^® 7000 series’ high-temperature performance so remarkable?

• Dimensional stability at continuous use temperatures up to 600°F (315°C).

• Rated for intermittent exposure up to 900°F (482°C) while resisting thermal shocks.

• The ability to retain stability in the face repetitive thermal cycling. Testing demonstrates that Meldin 7000 series materials exhibit less than .04% variation from their original dimension after cycling from 73°F to 500°F over a 2-day period.

Combined with several available self-lubricating fillers, this outstanding high-temperature stability helps extend component lifespan, reduce unexpected failures, and in many cases increase performance (temperature resistance is instrumental in allowing components to support higher load or speed use cases). Because Meldin^® 7000 series materials resist out-gassing in a vacuum, they can also be a great fit for high-purity applications such as semiconductor manufacturing equipment.

The Meldin^® 7000 series also brings substantial versatility to the table. Its many different grades allow manufacturers to select a polyimide material that is closely aligned to their application requirements. For example:

• Meldin^® 7001 – An unfilled grade that provides a cost-effective option for taking advantage of another one of this material’s valuable characteristics: excellent electrical and thermal insulation properties. Meldin^® 7001 can replace aluminum (while offering lower weight) and ceramics (while offering superior ductility and machinability) in structural applications.
• Meldin^® 7021 – Combines self-lubrication, low friction, and high-temperature resistance to offer a strong all-around choice well suited for bearings, seals, thrust washers, and other low-wear applications.
• Meldin^® 7211 – Leverages a 15% graphite, 10% PTFE filler to deliver the lowest coefficient of friction of any material in the 7000 series.

These offerings are just a small sample of the full set of options available within the Meldin^® 7000 series. For the full list of formulations available, please see our product page here. Or, for a more in-depth look at how Meldin^® in opening up new opportunities for manufacturers to take advantage of high-temperature polyimides, please check out our deep dive.

High-temperature polyimides have a long and successful history. But historically, they have represented a high-cost solution that was economical only when nothing else would do (like when developing materials for a space mission). The Meldin^® 7000 series offers truly transformative potential because it makes the benefits discussed above available at a more efficient price point than was available in the past. Looking forward, the TriStar team expects this product line to drive increased usage of polyimide components across a more diverse set of applications than ever.

If you have questions about whether a Meldin^® 7000 series material is right for your application, we encourage you to reach out to our team. In our experience, high-performance materials like Meldin^® perform their best when they are carefully matched to specific applications requirements. And our engineering team is here to help!

Applications for high-performance polyimides have always been limited by one concern above all other: cost. But today, Saint-Gobain’s latest series of Meldin^® 7000 materials have the potential to fundamentally upend this traditional limitation. By providing the high-temperature performance long associated with polyimides at a more efficient price point, the Meldin^® 7000 series is poised to make polyimide thermosets viable in more applications than ever.

Polyimides: High-Performance, High-Temperature, and (Traditionally) High Cost

Thermoset polyimide materials offer extraordinary high-temperature performance alongside exceptional dimensional strength. That’s why you’ll find these materials used in some of the most challenging applications imaginable, like plasma chambers, jet engines, and even spacecraft.

In engineering terms, the only notable limitation of polyimides is their vulnerability to hot water and steam. Because polyimides are fabricated using a polycondensation process, hot water can cause the materials to “re-condensate” and fall apart. Aside from chronically hot and wet environments, polyimide components can be well suited to an immense range of applications. But traditionally, their usage has been sharply limited by another factor: cost. Historically, with limited suppliers and high prices, the advantages of these advanced materials have largely been confined to high-cost applications that demanded a high-temperature, high-performance solution.

Today, however, Saint-Gobain’s cost-effective Meldin^® 7000 series materials offer the potential to dramatically expand the potential range of applications that can harness the virtually unrivaled high-temperature performance of thermoset polyimides.

Meldin^® 7000 Series Offers New Economies for High-Performance Polyimides

The roots of Meldin^® are related to the history of another Saint-Gobain material offered by TriStar: Rulon. Meldin^® was originally developed as a filler for Rulon^® materials, but it has since expanded into a much broader range of thermoplastic products. For a deeper look at “Meldin^® 101” and the different product series available in this family, please see our guide here.

The Meldin^® 7000 series draws on the decades of engineering that have gone into making Meldin^® one of the most successful polymer families on the globe, extending this experience to a new pinnacle of performance with thermoset polyimide materials. Most importantly, this “new Meldin^®” can deliver the full range of performance benefits associated with high-performance polyimides at a far more economical price point than has traditionally been available in the marketplace.

These benefits include:

• Dimensional Stability for High-Temperature and Cryogenic Applications Alike: Meldin^® retains its dimensional stability at temperatures 100° above the point where Torlon^® and PEEK begin to deform. Meldin^® 7000 series even exceeds the high-temperature tolerance of Rulon^® by around 50°. And its robustness extends all way down to cryogenic applications, with low-temperature tolerance ranging to -400° F.
• Resistance to Out-Gassing in a Vacuum: a crucial characteristic not only in outer space (where Meldin^® is used in satellites) but any ultra-sterile vacuum environment, such as those employed in semiconductor manufacturing.
• Outstanding Component Service Life: like many other Meldin^® materials, the 7000 series offers a powerful combination of high strength, low friction, and self-lubrication options. These characteristics can help reduce maintenance needs, extend service life, and increase loads/speed tolerance.

TriStar is proud to be the sole North American distributor of Meldin^®, and we can’t wait to see manufacturers begin to make expanded use of these materials. Because cost has always been the single most important limiting factor in the employment of thermoset polyimides, we think the extraordinary value offered by the Meldin^® 7000 series will help transform the way these materials are used. TriStar’s customers will now be able to harness these materials to cost-effectively extend component life, reduce failures, and enhance performance across a broader range of use cases than ever!

If you’re interested in detailed material specifications for the Meldin^® 7000 series (and the entire Meldin^® family) please see our interactive materials database here. Or, you can find a more detailed breakdown of the options available in the 7000 series on our product page here.

If you have questions about whether Meldin^® is the right fit for your application, we encourage you to reach out to our engineering team using the button below.