MATERIAL DEVELOPMENT TO MEET 2004 LEV II EMISSIONS REQUIREMENTS FOR INTAKE MANIFOLD SEALING

摘要

Due to the California Air Resources Board (CARB) mandate for low emission vehicle(LEV) compliance, automotive manufacturers must comply with these new regulations to sell vehicles in the California market. Thirteen additional states have adopted the CARB guideline, which will force an across the board adoption of these standards. Air intake manifold seals are currently under scrutiny for sealed housing evaporative determination(SHED) testing. New materials have been developed to meet the LEV II requirements, Fluorocarbon(FKM), Saturated Nitrile(HNBR), Fluorosilicone(FVMQ), and Silicone(VMQ) materials will be discussed in terms of fuel permeation resistance . The structure activity relationship of the polymer backbone is a major contributor in permeation resistance and is discussed in detail. In addition, glass transition temperature will be discussed to address low temperature intake sealing.