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Updated: Jul 12, 2026

The Preparation and Properties of Thermo-reversibly Cross-linked Rubber Via Diels-Alder Chemistry
Published on: August 25, 2016
Characterisation of crosslinked elastomeric materials by 1H NMR relaxation time distributions
G C Borgia1, P Fantazzini, A Ferrando
1University of Bologna, Department ICMA, Viale Risorgimento 2, 40136, Bologna, Italy.
Abstract:
One of the most critical structural parameters in elastomeric materials is the density of cross-linking between the polymeric chains. This chemical feature greatly affects chain motions and is determinant in controlling mechanical properties of the final product. NMR techniques are widely and efficiently applied to investigation of such materials. In this study we have measured both transverse and longitudinal 1H relaxation times of a series of polybutadiene rubber samples with increasing crosslink density induced by chemical treatment. This approach allowed the observation of T(1) and T(2) decrease with the increase of crosslink density in the samples examined. The data obtained have been analyzed and compared to theoretical models.
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