Preparation Of Rubber Based Iron Particles Composites And Research Of Their Application In The Field Of Safety Engineering As Magnetorheological Elastomers

Polymer- based metal composites are of growing technological interest for their unique optical, electrical, thermal, magnetic properties compared with common single-phase polymer. The newly progress about polymer-based metal composites and their applications was reviewed based on the investigation of a large amount of literatures. It was found that magnetorheological elastomers (MR) composed of elastic polymer and metal iron particles had special mechanical properties that could be controlled by the magnetic fields. As a type of new electric-mechanic-coupling material or smart material, they held great promise in adaptive tuned vibration absorbers, stiffness tunable mounts, and automobile suspensions that were relative to safety. However the research about the preparation and MR effect of such material was not enough. Until now, MR elastomers that could be used in reality were not reported. To get MR elastomers with high performance, by means of material design, selecting and matching of metal iron particles and elastic polymer, a series of rubber or rubber-hybrid or polymer gels based metal iron particles composites were prepared by different methods and their MR effect and mechanical properties was studied. The factors on MR effect of each composite was discussed in detail including the composition and the way of preparing them and the interface between iron particles and the matrix etc. At last, one of the elastic polymer-based metal iron composite was selected as an sample to be used in the tuned vibration absorber as MR elastomer.In summary, the research contents of this thesis are as following : 1. RTV silicon rubber based iron particles composites were firstly prepared by directly mixing method. The influence of size of iron particles and its chemical modification or not on MR effect was discussed in detail. The results showed that iron particles with large size about 60 μm were adverse to MR effect for they were easy to subside during its preparation. MR effect could be improved obviously by modifying iron particles with organic reagent such as stearic acid. The effect on MR effect depended on the kinds of modifying reagent and method. Secondly...