Degradation of Polyamide-12 pipes aged in fuel
(English)In: Polymer degradation and stability, ISSN 0141-3910, E-ISSN 1873-2321Article in journal (Other academic) Submitted
In this work properties of polyamide-12 (PA12) fuel lines, exposed for ≤2400 h at 110°C and ≤26000 h at 50°C, containing fuels with different ethanol contents, were investigated. Dynamic mechanical thermal analysis indicated a sizeable loss of plasticiser during ageing. Viscosity measurements suggested that chain scission was an important mechanism of degradation at the higher temperature and size exclusion chromatography suggested that this was probably the case also at 50°C after long ageing times. The molar mass and polydispersity data indicated that the most degraded samples were those exposed to high ethanol contents at 110°C. Thermogravimetry showed that the onset temperature of the main degradation stage was 340-410°C (depending on heating rate). X-ray fluorescence spectroscopy and high performance liquid chromatography indicated migration of stabiliser and in the three-layered pipe, having two PA12 layers divided by a poly(vinylidene fluoride) barrier layer, the migration occurred preferentially from the inner pipe layer into the fuel.
Place, publisher, year, edition, pages
Polyamide 12, ageing, fuel lines, ethanol, degradation
Other Materials Engineering
IdentifiersURN: urn:nbn:se:kth:diva-12035OAI: oai:DiVA.org:kth-12035DiVA: diva2:299744
QS 201203272010-02-252010-02-232012-03-27Bibliographically approved