Characterization of barium titanate reinforced acrylonitrile butadiene rubber composites for flexible electronic applications: influences of barium titanate content

Abstract

The aim of this study was to develop high dielectric constant flexible polymers with a highly efficient and cost-effective approach using acrylonitrile butadiene rubber (NBR) as the polymer matrix and barium titanate (BT) as the high dielectric constant filler. The BT powder was synthesized with a solid-state reaction and was characterized using a particle size analyzer, XRD, SEM and Fourier transform infrared spectroscopy. NBR/BT composites were fabricated using an internal mixer with various BT loadings up to 160 phr. The influence of BT loading on the cure characteristics and mechanical, dynamic mechanical, thermal, dielectric and morphological properties was determined. The incorporation of BT in the NBR matrix shortened scorch time and increased delta torque. The mechanical properties, thermal stability and dielectric constant were greatly improved and increased with BT loading. The results suggest that the reinforcement effect was achieved due to strong hydrogen bonding or polar-polar interactions between NBR matrix and BT filler. This is further corroborated by the good dispersion of BT filler in the NBR matrix observed with SEM imaging. These findings can be applied to produce high-performance dielectric elastomers.

Mechanical and Dielectric Properties of a Flexible Anisotropic Rubber-Based Composite

“…Among them, the strength of pure rubber in the T and W directions reached 20 MPa and 21 MPa, respectively. Its tensile strength is about 9-times higher than that (2.15 MPa) of pure NBR prepared by the melt mixing method in the literature [19]. With the increase in CGF, the tensile strength of the material first increases and then decreases.…”

“…Different from hard resin-based or ceramic-based composite materials [4][5][6], due to the high elasticity of rubber, conductive rubber composite materials are used as sensors, thermistors, wearable electronic devices and electromagnetic material [7][8][9][10][11][12][13]. At present, in order to improve the microwave absorption of rubber-based composites, some conductive particles, such as carbon black (CB) [14][15][16], single-wall carbon nanotubes [17], multi-wall carbon nanotubes [18], barium titanate (BT) [19], M-type hexagonal ferrites [20], Pb (Mg 1/3 Nb 2/3 ) 0.65 Ti 0.35 O 3 powder [21] and carbonyl iron [22,23] are added alone. Alternatively, two kinds of conductive particles are added to the rubber matrix, such as CB and carbon nanotubes [24] and CB and strontium ferrite [25].…”

Physicochemical Studies on the Effect of Hexamine Addition and Ratio on the Properties of Acrylonitrile Butadiene Rubber Composites

“…Figure 8 shows the obtained dielectric constant, ϵ / spectra versus frequency for pure composite (NBR) and composites (NBR/HA) with various histamine ratios. Because the dipole orientation could not keep up with the rapid variations in the electric field, the dielectric constants of NBR and NBR/HA composites dropped with frequency [42–44] …”

“…Because the dipole orientation could not keep up with the rapid variations in the electric field, the dielectric constants of NBR and NBR/HA composites dropped with frequency. [42][43][44] Furthermore, the dipolar polarization created by the persistent dipoles in HA caused tended to grow with HA content. The persistent dipoles are due to an uneven charge density distribution between the NB and R atoms.…”

The role of chemical microstructures and compositions on the actuation performance of dielectric elastomers: A materials research perspective

“…It is interesting to note that the strong electrical polarization of BT particles in NBR matrix could enhance the overall electrical conductivity along with the dielectric performance. A more comprehensive study involving the dielectric performance of BT-NBR composites (solid state mixing by an internal mixer) and dependence of dielectric content on the resulting performance was reported by Luangchuang et al [65] The agglomeration of the filler (BT) is a major problem of a filler-rubber system. The agglomeration of the fine particles like BT can also affect the actuation performance.…”