Polymer Optical Fibers with VESTAMID®: The Clever Solution for Communication Infrastructure in Automotive Applications

• High transmission capacity by polymer optical fibers
• Two concerted PA 12 compounds form the protective jacketing

Marl - The High Performance Polymers Business Unit of Essen, Germany-based Evonik Industries offers various VESTAMID^® molding compounds for a dual-layer jacket system for polymer optical fibers (POF). The data carrier of the data bus system, a PMMA fiber, is mechanically protected by inner and outer layers of polyamide 12.

Polymer optical fibers most suitable
Hi-tech communication technology in automotive and mechanical engineering applications depends on light transmission. For industrial use, an optical fiber must have high transmission capacity and be economical, reliable, and, if necessary, fire resistant. In particular, optical fiber systems with polymer optical fiber (POF), whose elements can be up to ten meters long, offer the automotive industry the best ratio of data transmission to system price and are easily laid, even in applications requiring small bend radii. As their use over the last few years has shown, they are very robustly built for installation and continuous use. The optical fiber is fixed in such a way that it has a long service life and resists high pull-out forces, even under dynamic stress.

Dual-layer protective jacket of polyamide 12
With these requirements in view, the High Performance Polymers Business Unit has developed a VESTAMID^® dual-layer jacket system to protect the optical data carrier, a PMMA fiber. The first, black layer consists of a modified polyamide 12 and, as required, adheres firmly to the PMMA core. In addition to providing mechanical protection, it increases the refractive index by virtue of its color, so that light scattering is avoided and optical transmission improved. It is also suitable for laser welding, so that the optical plug-in connectors can be welded on.

By contrast, the second layer should adhere only slightly to the first so that the system can be easily fabricated. It must make the system resistant to aging and battery acids. A specially plasticized, halogen-free, flame-retardant VESTAMID^® molding compound with good chemical resistance and hydrolytic stability satisfies these requirements.