Light vehicle emission levels have decreased by more than 90% during the last 60 years. This has led to a reduction in not only CO2 levels, but also pollutants like carbon monoxide, hydrocarbons, and nitrogen oxides. Western regulations (North America, Europe) are tighter than most of the world, but regions like China and India are soon to follow. This means for OEMs that specified emission levels are so low that it is almost impossible for them to reach only by directly modifying combustion conditions (without any performance or comfort compromise). For this reason, the use of specific emission controlling systems has become a growing trend in recent years. High pressure exhaust gas recirculation (EGR) and crankcase ventilation (blow-by) have now been used for decades, and newer systems are being used today (e.g. selective catalyst reduction, low-pressure EGR). These new systems require a high level of chemical and thermal resistance and Arkema's long chain polyamide materials can be great solutions.
Vacuum & Blow-By Lines
Rilsan® HT (high temperature) polyamide resins are designed for metal and rubber replacement in high temperature air management applications. Used in vacuum control lines or turbocharged ventilation systems, this flexible PPA (polyphthalamide resin) offers excellent depressure and leakage resistance, combined with very good chemical and thermal resistance. Rilsan® HT grades may be used in temperature classes up to 180°C, and may be processed by corrugated or smooth tubing extrusion and thermoforming.
Rilsan® HT polymers have become a reference for under the hood applications that require resistance to high temperature and aggressive media management.
A recent addition to the product line, Rilsan® T PA1010, can be used up to 150°C. This resin offers a similar chemical resistance to that of PA12, however with a higher thermal resistance and much better mechanical properties at higher temperatures.
SCR Lines & Tanks
With diesel nitrogen oxide emissions becoming a growing concern, selective catalyst reduction (SCR) is being used more in today's vehicles. This shift is raising new challenges for high performance plastics where solutions must combine chemical resistance at different temperatures and excellent processability to be acceptable.
Arkema offers a wide range of grades that can help optimize the balance of thermal and chemical performance for your development.
Application key challenges:
- Outstanding long-term resistance to thermo-oxidation
(continuous use temperature up to 175°C with peaks up to 220°C)
- Chemical ageing at high temperatures
- Good barrier to urea & ammonia
- Resist freezing / heating cycles
- Support the volumetric expansion due to freezing
- Very good processability (as low as 4*1 mm hoses)
- PA610 - Rilsan® Tieflex S452 black T6L
- PA12 - Rilsamid® AESN black P110 TL
- Flexible PPA - Rilsan® HT CESV black P010 TL
Conductive Grades to Prevent Static Discharge
During the operation of fuel delivery systems or refueling of a vehicle, liquid fuel moving through non conductive components can lead to charge separation and the build-up of electrostatic charges. Conductive Rilsan® grades can help reduce the risk of spark discharge during operation of fuel delivery system and greatly improve the safety of the system.