| Magnetorheological(MR) rubber is a sort of the magnetorheological materials and composite materials with multi-functional magnetoelastic couple effects. MR rubber has an increasing attraction for the wide range application prospects due to thecontrollability of mechanical, electrical, magnetic etc under applied magnetic field. However, the MR rubber practical applications are limited for the insufficient mechanical properties and low MR effects. This dissertation aims to explore a high performance and practical MR rubber.First, the MR rubber based on the NR/SBR blend were studied, and the influences of carbonyl iron powders(CIPs) contents, carbon black contents, softeners contents and different coupling agent modified CIPs on the mechanical properties and MR properties were analyzed and discussed. The results showed the best mechanical properties and MR effects of the sample with 300 phr carbonyl iron, 40 phr carbon black, 15 phr softeners and utilizing silicane coupling KH-570 modifying CIPs.Second, the MR rubber based on the room temperature vulcanized silicone rubber was also studied, and the preparation of the nylon cord reinforced MR rubber was firstly exploringly studied. The influences of different contents of carbonyl iron and nylon cord on the MR effect and mechanical properties of MR rubber based on silicon rubber were analyzed and discussed. The results showed that the addition of nylon cord increase the zero-field shear storage modulus, and does not affect the MR effects meantime, and also increase the tensile strength greatly. But the samples SEM images show that the adhesion of nylon cord and silicone rubber is greatly poor, and the mechanical properties of silicone rubber matrix is low.It is not a suitable method increasing the best performances of the MR rubber.Finally, nylon cord reinforced MR rubber based on the NR/SBR blend without magnetic field was studied. The influences of the contents of surface modification CIPs and the nylon cord on the MR properties and mechanical properties of the nylon cord reinforced MR rubber based on the NR/SBR blend were analyzed and discussed. The results showed that the tensile strength are 8.4MPa, 17.8MPa with no nylon cord and three layers nylon cord, repectively. While the magnetorheological effect reduced for the addition of nylon cord to some extent. However, as the increment of the contents of surface modification CIPs, the MR and mechanical properties increased at the begining and then decreased. The integrated performances were optimal, with 8.23% MR effect, and the tensile strength of 12.2MPa when added 300 phr surface modification CIPs and one layer nylon cord. The surface structures were also studied using scanning electron microscopy, and found that a strong combination between nylon cord and MR rubber matrix relatively smooth and non-empty surface obtained. |
