The use of NMR relaxation and NMR imaging in studying the aging of rubber

Nuclear magnetic resonance was used to study the aging of rubber filler materials. The methods used are the common spin-echo 1H NMR including variable echo times and parameter-selective NMR 1H-imaging (material properties imaging). The decay of the echo-magnetization is discussed on the basis of a single chain model with a distribution of dipolar interactions. This model is based on the influence of a very fast but anisotropic local motion as well larger and slower motions, which are able to diminish the residual dipolar interaction. Carbon black filled natural rubber as well as silica and carbon black filled E(mulsion)- and S(olution)-SBR and milled tire rubber are the systems under investigation showing some characteristic features of the aging course observable by NMR.