Envalior introduces Durethan FLX-RTM, a new impact-modified PA6 material that delivers excellent low‑temperature mechanical performance and is specifically engineered for rotational molding of tank liners, delivering excellent melt flow for complex geometries and exceptional mechanical performance.

With rotational-molding specialist Elkamet, Dautphetal, Germany, the material has already been successfully processed into prototype tank liners.

Rotationally molded prototype liner produced by Elkamet using Envalior’s Durethan FLX-RTM.

Rotational molding without pinch-off and weld seams

Durethan FLX‑RTM addresses the growing importance of rotational molding in tank manufacturing. Rotational molding offers a highly economical single‑stage process that produces homogeneous components—eliminating pinch‑off seams typical of extrusion blow‑molded liners and weld seams required in multi-part injection‑molded designs.

Envalior’s heat‑stabilized compound offers high melt flowability for rotational molding, enabling precise formation of filigree screw‑thread areas or the integration of metal or aluminum boss parts. It also retains the strengths that characterize Durethan PA6 compounds for injection molding and extrusion blow molding.

Engineered for demanding hydrogen applications

Durethan FLX‑RTM is a heat‑stabilized, impact‑modified, easy‑flow PA6 compound based on low‑molecular‑weight polyamide 6 with excellent flow properties. It maintains strong mechanical performance thanks to best‑in‑class impact‑modification systems and heat‑stabilization packages.

Key performance attributes include:

• Low hydrogen permeability, providing a high barrier against small gas molecules

• Compatibility with liquid fuels, including CE10 gasoline and other apolar liquids

• Exceptional toughness at temperatures down to –40 °C

• High elongation and ductility

Combined, these properties support safe, durable liner solutions across a range of storage media and environmental conditions.

From material development to prototypes

Together with Elkamet, a leading specialist in technical plastics with decades of experience in rotational molding, blow molding, and extrusion, Envalior has produced several prototype parts using electrically heated molds, vacuum assistance, and nitrogen purging to translate the material’s intrinsic properties into outstanding part performance.

Integrated customer support across the entire development process

Envalior and Elkamet support manufacturers with a comprehensive range of services throughout all stages of component development. This includes design, processing, and manufacturing expertise built over many years in plastic liners for high‑pressure tanks of various sizes, designs, and media.

A distinct advantage is Envalior’s comprehensive hydrogen‑permeation data, which few material suppliers provide.