Spatially resolved investigations of network structure and cross-link density of differently cured and aged technical rubbers by NMR microscopy

摘要

Cross-link density is one major parameter determining the mechanical properties of technical rubbers.It can be measured spatially resolved by parameter selective ~1H NMR imaging and accroding transformation of NMR parameters such as spin density,relaxation times,and diffusion coefficients into materials properties.This transformation is based on the physical understanding of network dynamics.The results provide a detailed understanding of macroscopic properties on the molecular level.To investigate the influence of filler content,different curing conditions and oxidative aging processes on the dynamics of the rubber network,parameter selective NMR imaging experiments with respect to T_1,T_2,T_(1rho) and the dipolar correlation coefficient Q_(DCE) have been performed.