The electrorheological fluid composed of starch particles and silicone oil/transformer oil was dispersed into 107 silicone rubber, and then two types of electric elastomers were prepared in the absence and presence of a curing electric field, respectively. The storage modules were measured using dynamic mechanical analysis with the round disk compression clamp. The results indicate that the storage modulus sensitivity of electric elastomers composed of pure transformer oil is the highest, that of electric elastomers composed of pure silicone oil takes second place, and that of electric elastomers composed of mixture oil is the smallest. For the given starch concentration, the storage modulus sensitivity attains a maximum value of 3.88 when the mass ratio between the transformer oil and 107 silicone rubber is 1. For the given mass ratio of 1, the effects of starch concentration and the presence or absence of the curing electric field on the storage modulus of electric elastomers were studied. When the starch concentration is 5 wt %, the storage modulus of the elastomer without the electric field (denoted as A-elastomer) is 20.1 kPa, whereas that of the elastomer with the electric field (denoted as B-elastomer) is 101.8 kPa. The storage modulus sensitivity attains a maximum value of 4.07. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 119: 2991-2995, 2011