background and aims. the condensation silicone impression materials are available, but there is little knowledge of their accuracy after disinfection. the objective of this study was to evaluate the effect of the disinfection by spray atomization on dimensional accuracy of condensation silicone impressions. materials and methods. impressions were made on a stainless steel master model containin...

in this work, leather fibers were employed as a component of elastomeric compounds based on nbr, cr and epdm and studied were made on their effects upon curing characteristics and mechanical properties of the prepared compounds. evaluation of curing characteristics of the compounds demonstrated that leather fibers have no considerable effect on initial viscosity and curing time of the compounds...

We examine the elastic shear waves generated in a thin pre-stressed elastomer layer that is sandwiched between two relatively thick steel plates and is subjected to an elastic shear wave traveling in one of the steel plates. The elastomer layer has been deformed in uni-axial strain in advance, producing in the layer very large axial and lateral compressive stresses of the order of its bulk modu...

The mechanical response to electrical stimulation was investigated in a chiral smectic elastomer. The two-dimensional strain tensor in an elastomer film was precisely measured by tracking fluorescent beads dispersed on the film. Shear deformation in the film was clearly observed when an electric field was applied perpendicular to the film surface. The temperature dependence of the strain tensor...

The effect of interfacial friction on adhesion was studied by using a model system, in which a thin strip of silicone elastomer was peeled from a PDMS (poly(dimethylsiloxane)) treated glass slide. The fluorescent particle tracking method revealed that the elastomer stretches and slides on glass well before the crack faces open up. Interfacial energy dissipation due to friction, which is the pro...

The rheology is widely known as one of the basic methods for rubber investigations for many years. At the same time, a variety of other methods of physical and chemical analysis suitable is available for rubber industry. One of them, the Time-Domain Nuclear Magnetic Resonance (TD--NMR) Spectroscopy is very sensitive to structural properties of elastomer materials. Moreover, by using NMR it is p...

A device for controlling the transmittance of light over large areas, such as windows, is described. It is based on electrostatically induced surface deformation of soft dielectric elastomer sheets produced when a voltage is applied between two networks of electrically conducting nanowires on either side of the elastomer. Variations in the surface curvature are produced by the applied voltage r...

In this seminar, the liquid crystal elastomers (LCEs) and their building blocks – liquid crystals and polymers are presented. The specific rod-like molecular shape of liquid crystals forces LCEs to form a special molecular distribution of the underlying polymer network. This allows them expand up to 400 % with temperature, which could be used in applications. The physics of this spontaneous dis...

A mechanical strain field applied to a monodomain cholesteric elastomer will unwind the helical director distribution. There are similarities with the classical problem of an electric field applied to a cholesteric liquid crystal but also differences. Frank elasticity is of minor importance unless the gel is very weak. The interplay is between the director being helically anchored to the rubber...