Several high-performance material families — DuPont™ Zytel® long chain polyamide product family comprising 612 and renewably sourced 610 and 1010, DuPont™ Hytrel® thermoplastic elastomers, DuPont™ Zytel® PPA and DuPont™ Vamac® ethylene acrylic elastomer (AEM)—are readily available as potential solutions for applications ranging from mono- and multi-layer fuel lines, fuel vapor tubes, PCV hoses, air brake hose and tubing, brake line coatings, servo brake, vacuum tubes and fuel line connectors.
All these materials are already commercial in those applications, and many are based on renewably sourced ingredients, allowing automakers to adopt a more sustainable solution. DuPont has also introduced chemically modified Zytel® 610 and 612 products suitable for brake and fuel systems applications. These additional long chain polyamide materials complement the product offering and can be considered as replacements for PA12, depending on the automotive parts required:
Mono-and multi-layer fuel lines
Zytel® nylon long chain polyamides offer varying degrees of flexibility balanced with resistance to zinc chloride, calcium chloride, hydrolysis and permeation. Many of the products are based on renewable content from castor oil derived from the non-edible castor plant.
Hoses for positive crankcase ventilation (PCV) systems must resist aggressive blow-by vapors containing moisture, combustion by-products and unburned fuel. Depending on part design, flexibility and working conditions, DuPont can offer chemically modified and heat stabilized Zytel® PA612 or Vamac® Ethylene Acrylic Elastomer (AEM) for PCV hose applications.
Air brake hose and tubing
Zytel® nylon long chain polyamides offer superior chemical and stress cracking resistance for use in both mono- and multi-layer air brake hose and tubing applications. Hytrel® thermoplastic elastomer also offers a wide range of flexibility, mechanical strength and high temperature burst pressure resistance for these tube constructions.
Servo and vacuum brake tubes
Resins for servo brake vacuum tubes may differ in properties, depending on part design, working conditions, assembly process and OEM specification. Hytrel® thermoplastic elastomers offer the best combination of flexibility and thermal properties. Zytel® nylon long chain polyamides like Zytel® RS 1010 or chemically modified 610 offer superior chemical and ozone resistance.
Fuel line connectors
Zytel® HTN54 PPA offers excellent chemical resistance to automotive fuels including ethanol and methanol bio-fuels, and bio-diesel. Available in conductive and non-conductive grades, Zytel® HTN PPA provides better heat resistance than PA12. While the mold-shrinkage factors of Zytel® HTN54 PPA are not exactly the same as GR PA12, they can often be processed through the same tooling with little or no refinement required. Resins for Quick Connectors may differ in properties, depending on part design, working conditions, chemical and temperature resistance required. DuPont offers wide range of polyamide grades with and without glass reinforcement, suitable to meet all industry demand.
•Zytel® 77G33L and 77G43L BK : PA612 resins with 33% and 43% glass reinforcement. They represent a closest option to PA12 GR in Q connectors. Chemical properties similar to PA12 GR.
•Zytel® RS 30G30HSL and 30G50HSL BK : are Renewable Sourced PA610 containing 30% or 50% glass reinforcement. New RS resin in DuPont’s portfolio, can offer superior temperature resistance than PA12 GR.
DuPont has global resources to work closely with customers to help identify material solutions and provide technical support. For help understanding whether these materials can work in an application, or for more technical information, please contact DuPont.