Müller, AKRO develop lighter TPE/polyamide components

ERJ staff report (PR)

Lichtenfels, Germany - Müller Kunststoffe, the German arm of the Hexpol TPE group, has linked up with AKRO-Plastic of Niederzissen, Germany to deliver reduced-weight products that combine thermoplastic elastomers (TPEs) with polyamide (PA) materials.

For its part, Müller has developed a low-density, adhesion-modified TPE, with a specific gravity of less than 1 g/cm3. Part of the Lichtenfels, Bavaria-based company’s Dryflex A range of compounds, it is said to deliver optimal adhesion to two new modified-PA compounds in multi-component applications.

AKRO developed Akromid Lite and Akromid XtraLite to offer a range of technical polyamide compounds with a lower density while maintaining the typical properties of polyamide. The modified PA is said to offer enhanced chemical resistance and the same or better mechanical properties as standard PA6 or PA 6.6.

The partnership with AKRO is the response to a market demand for special material combinations from PA and TPE, said Sven-M Druwen, European sales coordinator for Hexpol TPE. Target applications, he said, include parts for automotive air and water management systems, where the TPE provides the necessary sealing, acoustic and bridging properties, while always keeping to the lightweight goal.

“The specifically developed TPE grades for [AKRO’s new] modified PA compounds offer excellent mechanical properties with the added benefit of lower density,” Druwen stated. “Our new Dryflex TPE low density adhesion modified grade supplements the PA to offer a complete package for 2K applications.”

The PA and TPE combination started with a 75 Shore A TPE grade and is to be complemented in a new series with various shore hardnesses. The partners also aim to provide an approved material system, which is tested according with the new VDI guideline 2019 - a new standard for testing adhesion of TPE on injected-moulded substrates.

Hexpol is seeing a growing need for “a kind of 360-degree approach” to polymer development, noted Druwen, who concluded: “It is no longer enough to work on an individual compound, knowledge of the complete process, polymer combinations and their interconnectivity is the key to success. We increasingly work with an inter-disciplinary team bringing together the final customer, part designer, materials experts and processors.”