Automotive cable ducts are used to organize cables and protect them from exposure to weather or damage. Cable ducts are complex parts that can be molded from EPDM rubber, and thermoplastic elastomers like TPVs and styrenic-based TPEs. There are several limitations with these current material technologies:

• EPDM: high density, long cycle times, unable to 2-shot mold, can’t be recycled

• TPV: difficulty de-molding parts with complex designs and severe undercuts Standard TPE-S: narrow processing window and deformation occurs during mold release resulting in stress-markings on part surface

In the manufacture of cable ducts there are key OEM requirements for both the material and the parts themselves. Regarding material requirements, VOC’s, fogging, and odor are primary considerations. Final part requirements are especially stringent, demanding a broad operational temperature range, flame resistance and good insulation properties, and the ability to withstand extreme weather conditions. The major obstacle in designing a material for cable ducts is balancing part performance and aesthetics with the most efficient molding process.

Teknor Apex developed the Sarlink ML-2300B Series of high-performance TPEs for injection molding automotive cable ducts. Available in 50 and 55 Shore A, these grades exhibit much higher flow than conventional TPE-S materials, requiring reduced pressures and processing temperatures to fill complex parts with ease. The resulting parts have a better surface quality due to the absence of stress marks after de-molding and a broader processing window which effectively reduces sink marks.

Sarlink ML-2300B Series – High Performance TPEs

• Lower viscosity for improved moldability
• Good surface appearance
• Excellent UV resistance
• Adhesion to PP-LGF
• Available in 50 and 55 Shore A, in black