The constitutive relation and electromechanical stability of Varga-Blatz-Ko-type compressible isotropic dielectric
elastomer is investigated in this paper. Free-energy in any form, which consists of elastic strain energy and electric
energy, can be applied to analyse the electromechanical stability of dielectric elastomer. The constitutive relation and
stability is analyzed by applying a new kind of free energy model, which couples elastic strain energy, composed of
Varga model as the volume conservative energy and Blatz-Ko model as the volume non-conservative energy, and electric
field energy with constant permittivity. The ratio between principal planar stretches m(t0) (λ2 = m(t0)λ1), the ratio
between thickness direction stretch and length direction stretch 0 n(t0) (λ3 = n(t0)λ1 ), and power exponent of the
stretch k(t0) are defined to characterize the mechanical loading process and compressible behavior of dielectric
elastomer. Along with the increase of material parameters m(t0) , n(t0) , k(t0) and poison ratioV , the nominal
electric field peak is higher. This indicates that the dielectric elastomer electromechanical system is more stable.
Inversely, with the increase of the material parameter α , the nominal electric field peak, critical area strain and the
critical thickness strain increase, coupling system is more stable.
The synthesis of massive arrays of monodispersed carbon nanotubes that are self-assembled on hydrophilic
polycarbonate membrane is reported. This approach involves individual carbon nanotube manufacturing by non-ionic
surfactant to aid in dispersion and nanotubes self-assembled for three-dimensional orientation by high press filtration.
The inherent capability of carbon nanotube and microstructure of well-packed arrays predominate excellent conductive
properties of massive arrays. These potential applications of nanometer-sized sensor, probe and energy resistor have
been characterized in this study. Furthermore, the route toward application of self-assembled regular arrays, as heat
transmission intermedium, has been carried out by activating shape-memory polymer. The electrical conductivity of
insulating polymer is significantly improved by assembled carbon nanotubes, resulting in shape recovery behavior of
nanocomposite being driven by electrical resistive heating.
Currently aircraft structural composites are commonly protected using approaches such as laying of metallic meshes and
foils. However, these are not ideal solutions because they add significant weight and may be difficult to repair. In this
paper, we used multi-walled carbon nanotubes(MWNTs) and short carbon fiber(SCF) as reinforcement, and epoxy resin
as matrix, prepared conductive nanocomposites for lightning protection of aircraft. MWNTs and SCF as conductive
filler, they via acidification and surface treatment, mechanical milling, ultrasonic dispersion method, the CNTs/SCF
Epoxy (EP) conductive nanocomposites were prepared by casting method. The characterizations of materials
microstructure, electrical and mechanical properties were investigated by scanning electron microscope (SEM),
resistance instrument, and tensile test machine and indentation experiments. Result proved that surface treatment carbon
nanotubes and short carbon fiber can be evenly spread over the epoxy matrix, and form three-dimensional conductive
network in the epoxy matrix. This makes the resistance of composite materials greatly reduced, improved conductive
performance. The characterization of materials mechanical properties also showed that the addition of nano-conductive
filler, but also significantly enhanced the material elastic modulus and hardness.