We extend a model regarding the reinforcement of nanofilled elastomers and thermoplastic elastomers. The model is then solved by numerical simulations on mesoscale. This model is based on the presence of glassy layers around the fillers. Strong reinforcement is obtained when glassy layers between fillers overlap. It is particularly strong when the corresponding clusters—fillers + glassy layers—percolate, but it can also be significant even when these clusters do not percolate but are sufficiently large. Under applied strain, the high values of local stress in the glassy bridges reduce their lifetimes. The latter depend on the history, on the temperature, on the distance between fillers, and on the local stress in the material. We show how the dynamics of yield and rebirth of glassy bridges account for the nonlinear Payne and Mullins effects, which are a large drop of the elastic modulus at intermediate deformations and a progressive recovery of the initial modulus when the samples are subsequently put at ...

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A Microscopic Model for the Reinforcement and the Non Linear Behaviour of Filled Elastomers and Thermoplastic Elastomers (Payne and Mullins Effects)

Industrial decarbonization is a daunting challenge given the relative lack of low-carbon options available for “hard to decarbonize” industries such as iron and steel, cement, and chemicals. Hydrogen, however, offers one potential solution to this dilemma given that is an abundant and energy dense fuel capable of not just meeting industrial energy requirements, but also providing long-duration energy storage. Despite the abundance and potential of hydrogen, isolating it and utilizing it for industrial decarbonization remains logistically challenging and is, in many cases, expensive. Industrial utilization of hydrogen is currently dominated by oil refining and chemical production with nearly all of the hydrogen used in these applications coming from fossil fuels. The generation of low-carbon or zero-carbon hydrogen for industrial applications requires new modes of hydrogen production that either intrinsically produce no carbon emissions or are combined with carbon capture technologies. This review takes a sociotechnical perspective to examine the full range of industries and industrial processes for which hydrogen can support decarbonization and the technical, economic, social and political factors that will impact hydrogen adoption.

Industrial decarbonization via hydrogen: A critical and systematic review of developments, socio-technical systems and policy options

In this paper the magnetomechanical properties of magnetorheological (MR) elastomers with isotropic and anisotropic structure are examined A method for manufacturing magnetorheological elastomers (MRE) with thermoplastic elastomer matrix and 60  µm iron particles is presented The influence of various chemical compositions on the material parameters is investigated The properties of isotropic and anisotropic MR elastomers are examined in a wide range of mechanical and magnetic stimulations Test samples are subjected to cyclic shearing with a constant frequency of 1 Hz The change in magnetomechanical properties is expressed by the relative change of hysteresis loop area δW and stress amplitude δτ

https://iopscience.iop.org/article/10.1088/0964-1726/20/8/085006/pdf

Magnetomechanical properties of anisotropic and isotropic magnetorheological composites with thermoplastic elastomer matrices

Mechanical responses of Ecoflex silicone rubber: Compressible and incompressible behaviors

Fracture mechanical characterization and lifetime estimation of near-homogeneous components produced by fused filament fabrication

Cyclic tests on cracked round bars as a quick tool to assess the long term behaviour of thermoplastics and elastomers

Comparison of steady-state and transient thermal conductivity testing methods using different industrial rubber compounds

Materials used for the oil and gas industry are exposed to high pressure, high temperature and several aggressive fluids and gases. Concerning the still rising oil and gas product demand the development of new oil and gas valves is indispensable. Therefore, new reliable materials to guarantee facility safety at extreme operating conditions are needed. The presented study deals with a specific failure, the rapid gas decompression failure, which occurs due to the exposure to such extreme conditions. This failure leads to crack initiation, crack growth and in the worst case to the complete fragmentation of the component. For the characterization of this failure a hydrogenated acrylonitrile butadiene based rubber with an acrylonitrile content of 36% was exposed to several temperatures, saturation pressures, gas mixtures and different depressurization rates. Whereas, the rising testing temperature leads to decreasing volume change during the depressurization, the increase in saturation pressure, a higher decompression rate and a higher amount of carbon dioxide clearly lead to an increasing of the maximum observed volume change. Based on the observed volume change and the material ranking, determined using common testing standards NACE International (2003) and NORSOK (2001) a correlation to polymer physical principals was established.

Rapid Gas Decompression Performance of elastomers – A study of influencing testing parameters

We discuss the development of a method for the determination of the material properties of rubber and rubberlike materials within the context of a novel constitutive framework that has bee...

Determining material properties of natural rubber using fewer material moduli in virtue of a novel constitutive approach for elastic bodies

Concerning the still rising demand for oil and gas products, the development of new reliable materials to guarantee the facility safety at extreme operating conditions is an utmost necessity. The present study mainly deals with the influence of different carbon black (CB) filled hydrogenated nitrile butadiene rubber (HNBR), which is a material usually used in sealing applications, on the rapid gas decompression (RGD) resistance in harsh environments. Therefore, RGD component level tests were conducted in an autoclave. The supporting mechanical and dynamic mechanical property analysis, the microscopic level investigations on the material and failure analysis were conducted and are discussed in this work. Under the tested conditions, the samples filled with smaller CB primary particles showed a slightly lower volume increase during the compression and decompression phases; however, they steered to a significantly lower resistance to RGD. Transmission electron micrographs revealed that the samples filled with smaller CB particles formed larger structures as well as densified filler networks including larger agglomerates and as a consequence a decrease effective matrix component around the CB particles. Apparently, at higher loading conditions, which already deliver a certain level of mechanical stresses and strains, the densified filler network, and especially a lower amount of effective matrix material composition, adversely affect the RGD resistance. SEM-based fracture analysis did not identify any influence of the CB grades tested on the crack initiation site; however, it revealed that the cracks initiated from existing voids, hard particles, or low strength matrix sites and propagated to the outer surface.

https://www.mdpi.com/2073-4360/11/1/61/pdf

Bernd Schrittesser

Papers

Cyclic tests on cracked round bars as a quick tool to assess the long term behaviour of thermoplastics and elastomers

Comparison of steady-state and transient thermal conductivity testing methods using different industrial rubber compounds

Rapid Gas Decompression Performance of elastomers – A study of influencing testing parameters

Determining material properties of natural rubber using fewer material moduli in virtue of a novel constitutive approach for elastic bodies

The Effect of the Surface Area of Carbon Black Grades on HNBR in Harsh Environments.