Increased electroaction through a molecular flexibility tuning process in TiO2–polydimethylsilicone nanocomposites

Abstract

Flexible polymer materials with obvious electrostriction characteristics display a significant potential for application as novel potential actuators in the future. We report advanced TiO 2 -polydimethylsilicone (TiO 2 -PDMS) nanocomposites with electroaction that is effectively increased through a molecular flexibility tuning process. The increase in the electromechanical sensitivity (by 550%) and actuation strain (by 230%) under a low electric field in low elastic modulus TiO 2 -PDMS composites originates from the flexibility tuning process by the introduction of dimethylsilicone oil (DMSO). The DMSO is miscible with PDMS resulting in a uniform composition at the molecular level, which can significantly decrease the elastic modulus of the dielectric elastomer composites from 820 kPa to 95 kPa. The experimental results are interpreted using the swelling elastomers theory. It suggests that reducing the elastic modulus could be a good strategy to improve the actuation performance with a low electric field.

Highly reproducible quantification of apoptotic cells using micropatterned culture of neurons

“…Recently, elastomeric polydimethylsiloxane (PDMS) stencils used for cell cultures have been gaining wide popularity [12,13]. PDMS is inexpensive, mechanically strong, chemically and thermally stable, and (more important) biocompatible [14]. A PDMS stencil provides good adhesion to a glass surface without the need for additional bonding processes.…”

Remarkably improved electromechanical actuation of polyurethane enabled by blending with silicone rubber

“…Except the TPU 200 and pure PDMS with poor mechanical properties, all the blend lms performed better than pristine TPU. At a given electric eld, improved actuated strain can be induced by blending the PDMS and the TPU together even at the lowest content of PDMS (such as TPU 20 ). Furthermore, a continuous reduction in required applied electric-eld to reach the maximum actuated displacement, following a known trend induced by the reduction in the elastic modulus, can also be seen in Fig.…”

“…It can be observed that the TPU 80 reached the highest value of 5.1 among the binary blends. Considering the content of PDMS in this sample is even higher than in TPU 20 , TPU 40 , and TPU 60 , the relatively high dielectric constant should mainly benet from the interfacial polarization.…”

“…For instance, it is demonstrated that the actuated areal strain of DEAs can be largely enhanced by blending oil-type plasticizers into the rubber matrix. [18][19][20] Very recently, it is reported that silicone rubbers with a bottlebrushlike molecular architecture exhibited ultralow elastic modulus and an over 300% areal strain under an electric eld lower than 10 kV mm À1 . 21 All these ndings conrmed that decreasing the elastic modulus of elastomers to reduce the blocking force is very promising for advanced DEAs.…”

A simple method for reducing inevitable dielectric loss in high-permittivity dielectric elastomers

“…A great deal of focus during recent years has therefore been on increasing the dielectric permittivity of silicone DEs [4][5][6][7][8][9][10], which in turn leads to increased elastomer energy density and thereby increased strain at a given electric field. Large increases in dielectric permittivity have most often been accomplished through the use of metal oxide fillers creating silicone elastomer composites [11][12][13][14][15]. Such composite-type systems, though, do include the disadvantage that the Young's modulus of the elastomer is significantly increased -very often to a greater extent than dielectric permittivity -and thus no overall improvement in actuation strain is actually obtained.…”