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Quantifying rubber degradation using NMR

journal contribution
posted on 01.01.2000, 00:00 authored by Anthony SomersAnthony Somers, T Bastow, M Burgar, Maria ForsythMaria Forsyth, A Hill
Ageing can lead to the degradation of the tensile properties of natural rubber. The ageing process causes changes in the polymer segmental motion as well as the chemical structure, both of which can be monitored using nuclear magnetic resonance (NMR) spectroscopy. This work demonstrates that NMR can quantify rubber degradation due to ageing, and also that relatively simple NMR equipment can be used. This simpler equipment can be made portable and so could give a simple and fast indication of the condition of rubber in service. The 1H NMR transverse relaxation time, T2, and the 13C NMR spectrum using cross polarization and magic angle spinning (CP MAS) for samples taken at various levels of a degraded natural rubber liner were compared. These experiments showed that, as the level of degradation increased, the 1H NMR transverse relaxation time decreased. The 13C spectra showed considerable peak broadening, indicative of decreased mobility with increased level of degradation as well as the presence of degradation products. Further investigations using lower powered NMR equipment to measure the 1H NMR transverse relaxation times of two different series of natural rubbers were also performed. This work has shown that this simpler method is also sensitive to structural and mechanical property changes in the rubber. This method of monitoring rubber degradation could lead to the non-destructive use of NMR to determine the condition of a part in service.

History

Journal

Polymer degradation and stability

Volume

70

Issue

1

Pagination

31 - 37

Publisher

Elsevier Ltd.

Location

Oxford, England

ISSN

0141-3910

eISSN

1873-2321

Language

eng

Publication classification

C1.1 Refereed article in a scholarly journal

Copyright notice

2000, Elsevier Science Ltd. All rights reserved.