The reinforcement of silicone rubber (SR) imparted by different types of fillers was investigated. Glass fiber (GF), wollastonite and fluoro rubber (FR) as nontraditional filler for rubber were compounded SR and mechanical properties of the prepared composites were evaluated. The addition of silane pretreated GF and wollastonite into SR, tensile strength, abrasion resistance and tear strength of the composites improved considerably. The improvement in the properties was assigned to an increased interaction between the filler and the polymer matrix. For the SR/FR composites system, the elongation at break was increase with increasing concentrations of FR due to sponge like structure resulting from poor compatibility between the two components. To investigate the production potential of extrusion processing method, prepared composites were extruded in a rod type sample. During the curing stage, GF, wollastonite and FR lead to the formation of void in the matrix resin. When GF and wollastonite were treated with silane, the void formations were reduced significantly. The silane treatment process improves not only mechanical strength but also processibility of SR composites in dry conditions. (c) 2007 Wiley Periodicals, Inc.