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

• Main Authors: Nanying Ning, Minglu Wang, Jing Zhang, Liqun Zhang, Ming Tian
• Format: Article
• Language: English
• Published: Taylor & Francis Group 2015-10-01
• Series: International Journal of Smart and Nano Materials
• Subjects: graphene oxide (GO)-encapsulated silica (SiO2) hybrids; electrostatic self-assembly; polydimethylsiloxane (PDMS) elastomer; dielectric constant (k) and mechanical properties; actuated strain at low electric field
• Online Access: http://dx.doi.org/10.1080/19475411.2015.1130757
• ISSN: 1947-5411; 1947-542X

Herein, graphene oxide (GO)-encapsulated silica (SiO2) hybrids (GO@SiO2) were prepared via electrostatic self-assembly of the 3-aminopropyltriethoxysilane (APS)-modified SiO2 and GO. The as-prepared GO@SiO2 was introduced into polydimethylsiloxane (PDMS) elastomer to simultaneously increase the dielectric constant (k) and mechanical properties of PDMS. Then, the in situ thermal reduction of GO@SiO2/PDMS composites was conducted at 180°C for 2 h to increase the interfacial polarizability of GO@SiO2. 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@SiO2 (RGO@SiO2)/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@SiO2, 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@SiO2, indicating a good reinforcing effect of RGO@SiO2 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.