Loading…

Apparent reversal of physical ageing in amorphous glassy polymers by electron beam irradiation

It has been found that electron beam irradiation of physically aged, glassy polymeric films results in an apparent reversal of physical ageing (i.e. ‘deageing’) as determined by differential scanning calorimetry and yield stress behaviour. This is the first reported observation of ‘deageing’ in glas...

Full description

Saved in:
Bibliographic Details
Published in:Polymer (Guilford) 1993-01, Vol.34 (5), p.915-924
Main Authors: McHerron, Dale C, Wilkes, Garth L
Format: Article
Language:English
Subjects:
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:It has been found that electron beam irradiation of physically aged, glassy polymeric films results in an apparent reversal of physical ageing (i.e. ‘deageing’) as determined by differential scanning calorimetry and yield stress behaviour. This is the first reported observation of ‘deageing’ in glassy polymers that does not involve heating above the glass transition or an imposed deformation process. Effects of dose level and dose rate on the physically aged state of polystyrene, poly(methyl methacrylate) and polycarbonate have been determined. The specific deageing behaviour has been found to be material-dependent and the extent of deageing is proportional to the total absorbed dose. The experimental results support a proposed hypothesis that this deageing phenomenon is the result of radiation-induced internal gas evolution, which produces an increase in free volume and corresponding reversal of physical ageing.
ISSN:0032-3861
1873-2291
DOI:10.1016/0032-3861(93)90208-R