Interface detection in poly-ethylene terephthalate–metal laminates using variable energy positron annihilation

Thin coatings of poly-ethylene terephthalate (PET) on metal (“laminates”) have been studied with a variable energy positron annihilation technique. A correlation between PET crystallinity and the positron annihilation parameter S related to the free volume in the polymer is found. It is shown that b...

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Bibliographic Details
Authors: Escobar-Galindo, Ramón, Schut, Henk, Veen, A. van, Rastogi, Rajeev, Vellinga, Willem Pier, Meijer, H.E.H.
Format: article
Status:Published version
Publication Date:2005
Country:España
Institution:Universidad de Sevilla (US)
Repository:idUS. Depósito de Investigación de la Universidad de Sevilla
OAI Identifier:oai:idus.us.es:11441/147631
Online Access:https://hdl.handle.net/11441/147631
https://doi.org/10.1016/j.tsf.2004.11.045
Access Level:Open access
Keyword:Interfaces
Positron spectroscopy
Polymers
Adhesion
Description
Summary:Thin coatings of poly-ethylene terephthalate (PET) on metal (“laminates”) have been studied with a variable energy positron annihilation technique. A correlation between PET crystallinity and the positron annihilation parameter S related to the free volume in the polymer is found. It is shown that buried interfaces in these systems may be detected provided the S parameter of the polymer coating is lower than that of the substrate and higher than that of the surface. Also it is found that large positron diffusion lengths in the substrate favour interface detection. Further, changes in S parameter of PET–metal laminates were measured during uniaxial deformation and shown to be in qualitative accordance with a very simple model description that accounts for changes in free volume in PET during plastic deformation as well as the area fraction of cracks occurring in the PET.