Simultaneously improved actuated performance and mechanical strength of silicone elastomer by reduced graphene oxide encapsulated silicon dioxide

Herein,graphene oxide(GO)-encapsulated silica(SiO 2)hybrids(GO@SiO 2)were prepared via electrostatic self-assembly of the 3-aminopropyltriethoxysilane(APS)-modified SiO_(2) and GO.The as-prepared GO@SiO 2 was introduced into polydimethyl-siloxane(PDMS)elastomer to simultaneously increase the dielectric constant(k)and mechanical properties of PDMS.Then,the in situ thermal reduction of GO@SiO_(2)/PDMS composites was conducted at 180℃ for 2 h to increase the interfacial polariz-ability of GO@SiO_(2).As a result,the values of k at 1000 Hz are largely improved from 3.2 for PDMS to 13.3 for the reduced GO@SiO_(2)(RGO@SiO_(2))/PDMS elastomer.Meanwhile,the dielectric loss of the composites remains low(<0.2 at 1000 Hz).More importantly,the actuated strain at low electric field(5 kV/mm)obviously increases from 0.3%for pure PDMS to 2.59%for the composites with 60 phr of RGO@SiO_(2),an eightfold increase in the actuated strain.In addition,both the tensile strength and elastic modulus are obviously improved by adding 60 phr of RGO@SiO_(2),indicating a good reinforcing effect of RGO@SiO_(2) on PDMS.Our goal is to develop a simple and effective way to improve the actuated performance and mechanical strength of the PDMS dielectric elastomer for its wider application.