Envalior Launches Halogen-Free Flame Retardant PBT at K 2025

It has dimensional stability, low electrical corrosion, strong electrical insulation at high temperatures, and hydrolysis resistance, creep resistance, and fracture resistance comparable to polyamide. With these performance characteristics, its use is now being considered for applications traditionally dominated by polyamide.

"We see enormous application potential, primarily for ultra-fast charging stations for electric vehicles with a charging voltage of 800 volts and above, 800-volt power systems for artificial intelligence data centers, and connectors for 48-volt auxiliary power systems for hybrid vehicles. Other potential applications include enclosures and electrical components in the rapidly growing smart grid equipment market."explained Dr. Jochen Endtner, Product Development Manager at Envalior Pocan®."

Envalior plans to add more material variants with different glass fiber contents to the new PBT, optimized for specific performance aspects. Material grades that can now be precisely marked in all colors using laser marking (e.g., using data matrix codes) are available. Envalior also offers new materials based on renewable raw materials (bio-based butanediol).

Elongation at break greater than 2.5%

One of the highlights of the new Pocan® PBT is its high elongation at break of over 2.5% (ISO 527-1, -2), which can compete with polyamide compounds containing flame retardant additives. Components made from this material absorb more energy under load, meaning they are less prone to breaking and are less likely to develop stress cracks. This enables greater design freedom and expands the potential applications of this compound. It maintains excellent elongation at break even after multiple extreme temperature changes, as the material has strong resistance to hydrolysis and thermal aging.

Excellent hydrolysis resistance and CTI.

The new compound exhibits excellent hydrolysis resistance in sample testing. After being stored for 1,000 hours at 85°C and 85% relative humidity, important mechanical properties such as elongation at break remain well above 70%. In long-term tests based on the stringent SAE/USCAR 2 Rev.7 standard of the Society of Automotive Engineers (SAE), it achieved USCAR Level 3. It is this high hydrolysis resistance that opens up applications for thermoplastics previously reserved for polyamides.

Due to its anti-tracking properties, this compound achieved the best rating of 600 in the CTI A test (Comparative Tracking Index, IEC 60112). Therefore, it meets the highest insulation grade requirements of IEC 60664-1. This rating also applies to orange and black, which is unique for PBT compounds reinforced with 25% glass fiber.

UL 94 fire test by the American Insurance Laboratory has been passed, with all color samples having a thickness of 0.75 mm and a rating of V-0. This is particularly important for color coding connectors in cable harnesses.

"The high flame retardancy and scratch resistance of this compound make it easier for designers to create very thin and compact components without compromising electrical safety. This results in reduced material consumption and optimal use of installation space."Endtner said."

The long-term stability of thermoplastics in hot air was also tested. For example, after being stored in hot air at 150°C for 3,000 hours, its tensile strength still remained at a high level.

No PFAS

Pocan® BFN4232ZHR S1 is free of halogenated components and per- and polyfluoroalkyl substances (PFAS), which have been controversial as forever chemicals. Additionally, its additives do not release any known harmful decomposition products, such as isocyanates or phosphine, during the injection molding process.

“Therefore, the design materials we provide do not require high levels of occupational safety measures and meet all current and anticipated regulatory requirements in the near future. Thus, our clients can trust that this compound can be used safely and sustainably over the long term.Endtner explained.

Envalior offers a variety of halogen-free flame retardant compounds from different material categories. These compounds are ideal for high-voltage connectors due to their high CTI value of 600, UL 94 V-0 rating, and excellent mechanical properties. For example, they include dimensionally stable, mechanically and thermally high-elastic polyphthalamide compounds ForTii® or various polyamide 66 products Akulon®. The latter includes grades that minimize the corrosion of silicone seals in connectors, helping to achieve permanent high sealing performance.

Please visit Envalior at K 2025 (Hall 6, Booth B11, October 8-15, 2025, Düsseldorf Exhibition Center, Germany) and the 2025 North American Battery Show (Booth #408, October 6-9, 2025, Detroit, Michigan, USA) for more information.