A Study of the Deterioration in the Mechanical Performance of Polymers Used in Multilayer Fuel Lines with Immersion in a standard Automotive Test Fuel.

摘要

Many multilayer fuel line structures are currently being developed for use in fuel handling systems in an effort to comply with pending legislation regarding reduced vapor emissions. This study examines the changes in the mechanical properties and glass transition temperatures (T_g) of the polymers used in multilayer tubes such as conductive Nylons, barrier layer materials including Fluoropolymers, and tie layers with immersion in the standard test fuel Fuel C at 25 °C. The changes in T_g, percentage mass uptake, swelling, mechanical properties such as tensile, flexural and impact were determined for different immersion times. The results show that a significant deterioration in the mechanical performance of many of these polymers was recorded. A corresponding decrease in T_g with increasing immersion time in the test fuel was observed.