High-actuation displacement with high flexibility for silicone rubber and few layer graphene composites

Abstract

Three-dimensional (3-D) sp2 hybridized few-layer graphene (FLG) is studied due to high properties. Thus, FLG was used as a filler work to reinforce different types of room-temperature-vulcanized (RTV) silicone rubber to improve its properties. The FLG was characterized by a medium surface area of 123 m2/g, low lamella thickness index (LTI) of 18–22 (which is identical to the number of graphene layers stacked), and carbon purity of 99.85 %. The LTI was calculated by dividing the surface area of FLG by the surface area of single-layer graphene (SLG). Composites were prepared by mixing FLG with different types of RTV silicone rubber by solution mixing. The tensile modulus was 0.78 MPa (Type-A) and 0.51 MPa (Type-B). The electrical properties shows that electric resistance fell to 6760 MΩ (Type-A) and 3300 MΩ (Type-B) at 20 phr of FLG. These improved properties were tested for application in a piezo-electric actuator. From 2 to 14 kV, the displacement increased by 600 % for Type-A silicone rubber and 540 % for Type-B silicone rubber at 15 phr of FLG in the electrode. A series of experiments demonstrate the dependency of the properties and piezo-electric actuation on the FLG loading and type of silicone rubber.