Microstructure and dynamic mechanical properties of magnetorheological elastomer based on ethylene/acrylic elastomer prepared using different manufacturing methods.

Magneto-rheological elastomer (MRE) is a kind of smart material based on elastomer matrix and it is divided into isotropic (i-MRE) and anisotropic MRE (a-MRE) depending on the magnetic particle arrangement. In the i-MRE, carbonyl iron particles (CIP) are randomly dispersed, while they form a chain-like structure in the a-MRE. Two manufacturing procedures of a-MRE have been introduced. The a-MRE-1 was manufactured by one-step process involving application of magnetic field and curing of matrix simultaneously. On the other hand, a-MRE-2 was manufactured by two-step process in which the magnetic field was applied to induce CIP orientation and then the matrix was cured. The microstructure and mechanical properties of MRE were characterised by scanning electron microscope, universal testing machine and dynamic mechanical analysis. The results showed that the CIP content in MRE had no effect on the cure properties. A chain-like structure existed in a-MRE-1, whereas the orientation structure of CIP in the a-MRE-2 was not as clear as that in a-MRE-1. The tensile strength of a-MRE-1 was the lowest because no interfacial reaction occurred between the CIP and the rubber molecules chain, whereas i-MRE had the highest tensile strength. [ABSTRACT FROM AUTHOR]