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Ethylene‐propylene‐diene monomer rubber, grafted with maleic anhydride functions (EPDM‐g‐MA) was organically reinforced by reactive extrusion from the in situ synthesis of a polyimide (PI) phase. The blends were reactively processed at 200°C in a twin‐screw extruder, with the PI content varying from 5 to 40 wt%. Transmission Electron Microscopy (TEM) revealed a very fine nodular dispersion of the PI phase with diameters ranging from 130 to 240 nm depending on the PI concentration. The reinforcement of the elastomer was evidenced with a sharp increase of the Young's modulus and the tensile strength, and the stiffness of the material was further increased with the PI content. The linear viscoelastic regime, as measured by the variation in storage modulus as a function of strain, was unaffected by this organic reinforcement, thus opening up an original way of controlling the Payne effect. Additionally, the cross‐linking of the blend with 20 wt% of PI with dicumyl peroxide (DCP) showed that the PI phase did not impact the creation of the cross‐linked network. The decrease of the swelling ratio and the improvement of the elastic recovery suggested that EPDM‐g‐PI copolymers can create a second network in the material, resulting in a higher apparent cross‐linking density. The mechanical properties of the cured blend showed a doubling of the Young's modulus and maximal stress values compared to those obtained for the pure matrix as well as a constant strain at break. Highlights: Ethylene‐propylene‐diene monomer rubber, grafted with maleic anhydride functions (EPDM‐g‐MA) was organically reinforced by reactive extrusion.The reinforcement was obtained from the in situ synthesis of a polyimide (PI) phase.The Young's modulus of cross‐linked EPDM containing 20 wt% PI was doubled.The linear viscoelastic regime was unaffected by this organic reinforcement.This original way of reinforcement opens the control of the Payne effect. [ABSTRACT FROM AUTHOR]

Thin layer activation (TLA) is already routinely utilised for online wear monitoring of metallic components with the radioisotope concentration (RIC) method for various tribological applications. However, many components in tribological systems are made of carbon-based bulk material (e.g. polymers) or have carbon-based wear resistant coatings (e.g. diamond-like carbon). By utilising the nuclear reaction 12C(3He,x)7Be, TLA can thus be employed in carbon-containing components. To evaluate the applicability of this approach for TLA in combination with the RIC method, three materials EPDM (ethylene propylene diene monomer), PEEK (polyether ether ketone) and DLC (diamond-like carbon), which are vastly utilised in tribology, were activated. Subsequently, the modulus of elasticity and hardness of the activated specimens were measured and evaluated if the material works for TLA. As EPDM developed cracks after the irradiation process, it is regarded to be not applicable for TLA and subsequent wear measurements. While the PEEK material revealed small changes in hardness values compared to non-irradiated samples, the irradiated DLC coating showed no detectable material changes. Both irradiated materials have been applied to representative tribological wear studies, for which the RIC results showed a good correlation with optical wear measurements.

This research evaluated the effects of hybrid fillers and mixing equipment on natural rubber (NR) and ethylene propylene diene monomer (EPDM) properties with an 80/20 ratio. Silica (Si), carbon black (C), china clay (CC), and calcium carbonate (Ca) were used as hybrid fillers. Mixing techniques using two-roll mill and an internal mixer were compared. The study focused on cure characteristics, mechanical properties, and thermal stability. The study found that incorporating hybrid fillers significantly improved the curing process. Blends prepared by an internal mixer had more consistent mechanical properties such as modulus, tear strength, and hardness compared to those prepared by two-roll mill. Blends with Si and C (NE-SiC) showed significant enhancements in tensile and tear strength. Although adding multiple fillers did not accelerate curing, it enhanced the modulus, indicating a potential synergistic effect. The internal mixer method resulted in better elongation at break, except for the NE-SiC-CC.Ca blend, which had reduced flexibility. Thermal analysis revealed higher thermal stability for blends with hybrid fillers, decomposing at elevated temperatures with larger residues, particularly in NE-SiC-CC and NE-SiC-CC.Ca blends. These research findings highlight the critical role of filler types and mixing methods in optimizing the performance of NR/EPDM rubber blends.

Ethylene propylene diene monomer (EPDM) is a synthetic rubber widely used in industry and commerce due to its high thermal and chemical resistance. Nanotechnology has enabled the incorporation of nanomaterials into polymeric matrixes that maintain their flexibility and conformation, allowing them to achieve properties previously unattainable, such as improved tensile and chemical resistance. In this work, we summarize the influence of different nanostructures on the mechanical, thermal, and electrical properties of EPDM-based materials to keep up with current research and support future research into synthetic rubber nanocomposites. [ABSTRACT FROM AUTHOR]

V‐belts are commonly used to transmit power between two distant pulleys. Therefore, a strong reinforcement for dimensional stability and thermomechanical properties are essential in power transmission belts. The influence of resorcinol formaldehyde resin (RFL) treated nylon short fibers in EPDM peroxide‐cured formulations was investigated, with concentrations ranging from 0 to 30 parts per hundred rubber (phr) in increments of five. The incorporation of nylon short fibers resulted in improved tensile and mechanical properties in EPDM vulcanizates. Specifically, the tensile stress at 100% elongation increased by 177% to (10.8 MPa), and the improvement in tear strength to 16.2% (75.7 N/mm) was observed. Among other functional requirements in a weak rubber like EPDM, enhanced tear strength is significant for its application in power transmission. Substantial reinforcement between the fiber‐elastomer matrix was confirmed via scanning electron microscopy, as evidenced by increased storage modulus (E′). Notably, there were no considerable effects on the curing rate or low‐temperature properties. Significant improvement in heat stability is observed through thermogravimetric analysis. These enhancements in mechanical and thermal properties might play a role in increased durability and performance in actual V‐ribbed belt applications. Highlights: This manuscript describes the effect of treated nylon 66 short fiber on EPDM V‐belt compound.A significant increase in storage modulus, tear strength, and thermal stability.A belt is made using the experimental formulation and it meets the performance requirement.Low fiber content (<15 phr) compounds are unsuitable for dimensional stability.High fiber content (>25 phr) compounds pose processing challenges. [ABSTRACT FROM AUTHOR]

This study investigates the profound impact of vulcanization methods on ethylene–propylene–diene monomer (EPDM) composites, with a particular focus on elucidating significant findings and achievements. Exploring eight composites, including sulfur and peroxide‐cured variations, we conducted an in‐depth evaluation of the crucial physico‐mechanical properties of the composites. The study extends to encompass the effects of vulcanization on heat aging parameters, providing a comprehensive understanding of the materials' resilience. Utilizing thermogravimetric analysis, differential scanning calorimetry, and Fourier transform infrared spectroscopy, our research delves into the processes, revealing critical insights into the thermal behavior and composition of the composites. Paint compatibility, a pivotal aspect in automotive applications, was rigorously examined through four different test methods. Surface morphology, investigated through scanning electron microscopy and atomic force microscopy, yielded valuable findings on the role of vulcanization in shaping surface roughness and enhancing paint compatibility. Additionally, the quantitative measurement of surface energy using the sessile drop method provided a deeper understanding of the adhesion properties. The findings distinctly underscore the superiority of peroxide‐cured composites, marking a significant stride toward their potential to revolutionize automotive applications. This research not only contributes to the knowledge base but also sets a foundation for advancements in EPDM composite materials, positioning them as key players in driving innovation within the automotive industry. Highlights: Developed a peroxide‐cured EPDM rubber composite with a rough surface.A rough surface is more paint‐compatible than a smooth surface.The roughness of peroxide‐cured EPDM is greater than that of sulfur‐cured one.Peroxide curing introduces more polar functional groups and cross‐links.Peroxide‐cured EPDM has higher thermal stability than sulfur‐cured EPDM. [ABSTRACT FROM AUTHOR]

This study investigates the mechanical properties and fracture behavior of polypropylene (PP)‐based blend‐nanocomposites comprising 30 wt.% ethylene–propylene–diene monomer (EPDM) and 5 wt.% SiO2 nanoparticles. Different mixing sequences were employed to prepare the nanocomposites, and the resulting morphology development and dispersion states of modifiers were analyzed. Mechanical performance of the nanocomposites was evaluated through quasi‐static and high‐speed dynamic fracture tests. The dispersion and distribution of SiO2 nanoparticles within the nanocomposites were significantly influenced by the mixing protocol. In impact fracture tests, the presence of nanoparticles exhibited a beneficial efffect on fracture energy, demonstrating a synergistic toughening effect of the soft EPDM and rigid SiO2 particles. Conversely, adverse effects were observed in quasi‐static tests. Essential work of fracture (EWF) parameters indicated an increase in the yielding component and a decrease in the necking‐to‐tearing component with SiO2 incorporation into the PP/EPDM blends. During impact loadings, the highest improvement in crack propagation resistance was observed in nanocomposites with nanoparticles localized around the rubbery domains forming a network‐like structure of EPDM/SiO2‐nanoparticles. Morphologies where rubber domains and nanoparticles were separately distributed in the PP matrix resulted in the lowest fracture parameters. Energy dissipation mechanisms were elucidated, revealing multiple void formation followed by matrix shear yielding as the primary source under both quasi‐static and impact fracture conditions. In the latter case, stress‐concentrating percolated structures in the PP matrix facilitated the nucleation of dilatational bands evolving into highly stretched void‐fibrillar structures upon further loading. These findings contribute valuable insights into tailoring nanocomposite morphologies for enhanced mechanical performance in different loading scenarios. Highlights: Fracture behavior of PP/EPDM/SiO2 ternary systems was evaluated by EWF methodology and Izod impact test.Rubber particles surrounded by silica nanoparticles led to a percolated morphology and as a result to superior impact resistance.EWF parameters were mostly controlled by the tearing‐related parts regardless of phase morphology.The impact toughness was mainly controlled by the dispersion and distribution characteristics of the SiO2 nanoparticles. [ABSTRACT FROM AUTHOR]

Abstract Increasing waste rubber recycling produces a specious range of products for many valuable applications. Waste Rubber/EPDM composite with different concentrations was prepared. Infrared spectroscopy (FTIR) is used to identify the chemical composition. A water absorption test, Dynamic mechanical analysis (DMA), and Thermal Gravimetric Analysis (TGA) were performed. The (75/25) WR/EPDM rubber composite exhibited the best behavior with the highest mechanical performance. Fe2O3 was added to (75/25) WR/EPDM rubber composite. Water absorption, FTIR, TGA, and DMA were investigated. The composite performance was improved with increasing Fe2O3 content. The linear attenuation coefficients (μ) were also measured as a function of the concentrations of Fe2O3 for γ-ray energy 662 keV by using 137Cs point source; the radiation shielding can be denoted by numbers of parameters like mass attenuation coefficient (μm), half value layer (HVL), Tenth value layer TVL and radiation protection efficiency (RPE%), radiation protection efficiency increased as Fe2O3 increased.

Increasing waste rubber recycling produces a specious range of products for many valuable applications. Waste Rubber/EPDM composite with different concentrations was prepared. Infrared spectroscopy (FTIR) is used to identify the chemical composition. A water absorption test, Dynamic mechanical analysis (DMA), and Thermal Gravimetric Analysis (TGA) were performed. The (75/25) WR/EPDM rubber composite exhibited the best behavior with the highest mechanical performance. Fe2O3 was added to (75/25) WR/EPDM rubber composite. Water absorption, FTIR, TGA, and DMA were investigated. The composite performance was improved with increasing Fe2O3 content. The linear attenuation coefficients (μ) were also measured as a function of the concentrations of Fe2O3 for γ-ray energy 662 keV by using 137Cs point source; the radiation shielding can be denoted by numbers of parameters like mass attenuation coefficient (μm), half value layer (HVL), Tenth value layer TVL and radiation protection efficiency (RPE%), radiation protection efficiency increased as Fe2O3 increased. [ABSTRACT FROM AUTHOR]

This study investigated the synergistic effect of carbon black/multi-wall carbon nanotube (CB/MWCNT) hybrid fillers on the physical and mechanical properties of Ethylene propylene diene rubber (EPDM) composites after exposure to high-pressure hydrogen gas. The EPDM/CB/CNT hybrid composites were prepared by using the EPDM/MWCNT master batch (MB) with 10 phr CNTs to enhance the dispersion of CNTs in hybrid composites. The investigation included a detailed analysis of cure characteristics, crosslink density, Payne effect, mechanical properties, and hydrogen permeation properties. After exposure to 96.3 MPa hydrogen gas, the hydrogen uptake and the change in volume and mechanical properties of the composites were assessed. We found that as the MWCNT volume fraction in fillers increased, the crosslink density, filler–filler interaction, and modulus of hybrid composites increased. The hydrogen uptake and the solubility of the composites decreased with an increasing MWCNT volume fraction in fillers. Moreover, after exposure to hydrogen gas, the change in volume and mechanical properties exhibited a diminishing trend with a higher MWCNT volume fraction. We conclude that the hybridization of CB and CNTs formed strong filler–filler networks in hybrid composites, consequently reinforcing the EPDM composites and enhancing the barrier properties of hydrogen gas. [ABSTRACT FROM AUTHOR]

The effects of octaphenylsilsesquioxane (OPS), fumed silica, and silica aerogel on the thermal insulation properties of ethylene propylene diene monomer (EPDM) rubber were studied. On this basis, two kinds of fillers with good performances were selected to study the thermal insulation of an EPDM full-formula system. The results show that the addition of fumed silica or silica aerogel had a positive effect on the thermal insulation performance of EPDM rubber and its composite. A 30 wt% silica aerogel can be well dispersed in the EPDM rubber system and with a lower thermal conductivity compared with fumed silica. EPDM composite with 23.4 wt% fumed silica can produce more char residues at 1000 °C than at 500 °C in a burn-through test and formed the compact and porous char at 1000 °C, which had a lowest thermal conductivity. EPDM composite with fumed silica cannot be burned through 1000 °C burning, and comparison with silica aerogel revealed that it achieved the lowest back temperature and had a temperature of 388 °C after 800 s. [ABSTRACT FROM AUTHOR]

Aromatised wine-based beverages and regular wines are commonly bottled on the same bottling line. Sealings installed in the bottling line absorb added aroma compounds from the aromatised wine-based beverages and a subsequent release of the absorbed aroma compounds from the sealings was monitored during cleaning sequences and in subsequent products. Such unintentional carryover is associated with the risk of violating the legal ban of any aromatisation of regular wine. If cleaning is carried out according to good manufacturing practice (GMP) and traces of aroma compounds in the subsequently bottled wine show no sensory significance, this unintended aroma carryover will be considered by the German Federal Ministry of Nutrition and Agriculture as technically unavoidable and has no legal consequences. The risk of aroma absorption and aroma carryover have been investigated in different foods (orange juice, milk, and wine) and simulated in model systems using a beaker, but no real bottling scenario had been investigated till now. To fill the knowledge gap we investigated the potential aroma carryover in a pilot plant, and in two different wineries during three bottlings of aromatised wine-based beverages and subsequent regular sparkling wine. Monitoring of installed sealings revealed the uptake of seven aroma compounds and further release of aroma compounds during a recommended cleaning sequence and subsequent contact with wine. A sensory significant aroma carryover into the subsequent wine that had been circulating for 24 hours in the pilot plant was observed only for α-ionone, which exceeded its odour detection threshold in white wine after 8 hours. Regarding the three bottlings of aromatised wine-based beverages and the subsequent sparkling wine, we recorded the uptake of γ-decalactone, eugenol, and trans-cinnamaldehyde in the sealings, and their further diminishment during the implemented cleaning of the wineries and subsequent bottling of a sparkling wine. During the short residence time of the product in the bottling line, no sensory and analytical differentiation of the pre-bottled and bottled sparkling wines was observed.

Excessive plasticizer migration to the insulation will have a serious impact on the safety of solid propellants. In this paper, the anti-migration EPDM insulation was prepared by introducing vinyl triethoxysilane functionalized GO (GS) as modifiers to prevent the migration of energetic plasticizers. The anti-migration performance at different temperatures was evaluated by immersion tests. The concentration of mixed plasticizers that migrated into the EPDM/GS-3 at 30 °C was decreased from 24.7% to 20.4% (17.4% decrease). The results confirmed that the introduction of GS prevented the migration of plasticizers to the EPDM insulation. The SEM results showed that GS was well-dispersed in the insulation, and there is strong interfacial interaction between GS and EPDM chains. Our research provided a new method to prepare EPDM insulation with excellent anti-migration performance.

Insulation is considered the weakest link in electrical equipment. The combined effects of special working conditions in coal mines and aging factors such as electrical, thermal, and mechanical stresses make it difficult to determine the aging mechanism and evaluate the condition of EPDM insulation for high-voltage cables used in mines. This paper introduces the basic performance and aging factor types of EPDM insulation for high-voltage mobile flexible cables used in coal mines. Based on the physical, chemical, mechanical, and electrical properties of EPDM under the influence of multiple aging factors, the aging mechanism of EPDM is proposed. This paper summarizes the basic principles and existing problems of online monitoring methods for insulation resistance, partial discharge, dielectric loss factor, and temperature of mining high-voltage cables. The paper summarizes the current research status of insulation status evaluation methods for mining high-voltage cables. The paper introduces the evaluation methods for insulation status of multi parameter based on improved radar map and single parameter based on dielectric loss mining high-voltage cables. To cope with the development of coal mine intelligence, on the one hand, it is suggested to do research on intelligent perception and control of mining electrical equipment to compensate for the lack of state perception and state evaluation feature quantities. On the other hand, it is necessary to study lightweight models or algorithms to reduce the computational complexity, parameter quantity, and analysis time of intelligent terminals near devices. It improves the feasibility of state evaluation technology, and lays the foundation for achieving intelligent analysis and decision-making.

Ethylene propylene diene monomer (EPDM) is a synthetic rubber widely used in industry and commerce due to its high thermal and chemical resistance. Nanotechnology has enabled the incorporation of nanomaterials into polymeric matrixes that maintain their flexibility and conformation, allowing them to achieve properties previously unattainable, such as improved tensile and chemical resistance. In this work, we summarize the influence of different nanostructures on the mechanical, thermal, and electrical properties of EPDM-based materials to keep up with current research and support future research into synthetic rubber nanocomposites.

This research studies the effect of borax on the thermal stability and thermal kinetic behavior of ethylene-propylene-diene (EPDM) rubber composites. Using a laboratory two-roll mill at room temperature, carbon-black (N-220) as filler, and other additives such as zinc oxide, stearic acid, and paraffin oil were incorporated into the EPDM rubber matrix. The composite was prepared at different borax concentrations (25 and 50 phr). Thermogravimetric analysis was performed to characterize borax's effect onthermal stability before and after borax addition. Added borax to the host composite rubber (EPDM composite without borax) significantly improved the composite's thermal stability. Borax-loaded composites behave differently at various temperatures. To investigate the kinetic-thermal analysis of the prepared samples, three different models were applied. The activation energy (Ea) and frequency factors (A) for the Horowitz-Metzger, Broido and Coats-Redfern models were calculated. These models were compared and discussed based on their results. First-order decomposition also represented the main decomposition stage. Kraus and Cunnen-Russel models were used to test the interaction between rubber and borax based on previously published swelling results. No interaction was found between rubber and borax.

Abstract Modeling of complex systems requires large and expensive computational systems. Costs and processing time can be reduced by more than half in a well‐managed cloud environment. Modeling the flow of ethylene propylene diene monomer (EPDM) through a Garvey die was achieved by employing the latest cloud computer technology commercially available at a modest cost. The description of the stress–strain behavior for EPDM was done using the Otswald‐de Waele model. The results demonstrate that at higher velocities, the flow lines do not follow a smooth profile upon exiting the die, which indicates instabilities that may affect on the finished surface. Prediction of extrudate flow instabilities gives a computational option to make an initial estimate of permissible extrusion speeds.

In this study, ethylene propylene diene monomer (EPDM)-lead monoxide (PbO)-magnetite (Fe3O4) composite was prepared and changes in its properties with different gamma irradiation doses (50, 100, 200, 300, 500, and 1000 kGy) were investigated. Characterizations of irradiated EPDM-metal oxide composites were performed by X-ray Diffractometer (XRD), Field Emission Scanning Electron Microscope (FESEM) and Universal Testing Machine (UTM). It was observed that the synthesized sample shows an amorphous nature beyond the 500 kGy irradiation dose. The FESEM morphographs of irradiated samples show an increase in fracture size with an increase in irradiation dose. The mechanical tests have shown that prepared samples retain their mechanical strength up to ∼100 kGy. In addition, the effect of thermal and electrical properties on irradiation dose has also been studied. The synthesized samples show good thermal stability up to ∼500 kGy. The AC conductivity of the synthesized EPDM-metal oxide composites has been observed to increase slightly with an increase in irradiation dose. It was observed that synthesized EPDM-metal oxide composites are relatively good radiation resistant candidates and can be used for radioactive waste disposal management applications.

One of the significant problems of our time and future is environmental pollution. There are many factors that cause environmental pollution and the main concerns are waste material. Since production, consumption and service activities have increased with rapid industrialization and increasing population. Waste assessment is a process that includes minimization, separate collection at source, intermediate storage, pre-treatment, the establishment of waste transfer centers, recovery and disposal when necessary, which are qualified as outputs as a result of activities such as production, application and consumption. The purpose of waste assessment is to ensure the process of wastes generated by human action without harming the environment and human health. In this context, re-evaluation of agricultural and aquaculture products that turn into waste after being used as a product is important both in terms of economic and environmental pollution. Herein, the use of cumin black pulp, which is waste at the end of black seed oil production, as a bio-based filler material in ethylene-propylene diene rubber (EPDM) was examined. Accordingly, the effects of cumin black pulp added to the EPDM matrix at different content on the rheological, mechanical and crosslinking degree of EPDM were determined. With the use of 10 phr cumin black pulp, the mechanical and rheological properties of EPDM and the degree of crosslinking increased. The tensile strength and elongation at break of the EPDM/CB composites increased up to 11 MPa and 480% with the addition of 10 phr CB, respectively. In addition, it was revealed that the vulcanization parameters were also enhanced. Consequently, it has been concluded as a result of the analysis that the waste cumin black pulp can be used as a filling material in the EPDM matrix. Thus, it has been seen that a product in the state of waste can be recovered and become an economic value. [ABSTRACT FROM AUTHOR]

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This study used ethylene‐propylene diene monomers (EPDM), an elastomer, to develop foams incorporating clay as filler using simple compounding, chemical foaming, and peroxide‐mediated light crosslinking methods. The low‐temperature batch mixer was employed for compounding azodicarbonamide (ADC) as a foaming agent, dicumyl peroxide (DCP) as a crosslinker, followed by compression molding for sheet preparation and the high‐temperature foaming process. Fourier transform infrared spectroscopy (FTIR) equipped with a hot stage attenuated total reflection (ATR) was employed to elucidate the ADC decomposition and foaming. The DCP (0.25 phr) content was optimized based on the foaming expansion ratio (>4) and stability, which was further optimized in conjuncture with clay to generate high‐performance composite foams. The incorporation of 1% organoclay enhances the expansion ratio and specific tensile strength by >7 and ~ 270%, respectively, compared with EPDM foams without clay while displaying a density of 0.11 g/cm3. Overall, the developed foaming process can be extended to other elastomeric polymers for various applications such as protective gears (e.g., helmets and shin guards), thermal/sound insulation, packaging/containment, footwear soles, oil absorption, etc. [ABSTRACT FROM AUTHOR]

This study investigated the synergistic effect of carbon black/multi-wall carbon nanotube (CB/MWCNT) hybrid fillers on the physical and mechanical properties of Ethylene propylene diene rubber (EPDM) composites after exposure to high-pressure hydrogen gas. The EPDM/CB/CNT hybrid composites were prepared by using the EPDM/MWCNT master batch (MB) with 10 phr CNTs to enhance the dispersion of CNTs in hybrid composites. The investigation included a detailed analysis of cure characteristics, crosslink density, Payne effect, mechanical properties, and hydrogen permeation properties. After exposure to 96.3 MPa hydrogen gas, the hydrogen uptake and the change in volume and mechanical properties of the composites were assessed. We found that as the MWCNT volume fraction in fillers increased, the crosslink density, filler–filler interaction, and modulus of hybrid composites increased. The hydrogen uptake and the solubility of the composites decreased with an increasing MWCNT volume fraction in fillers. Moreover, after exposure to hydrogen gas, the change in volume and mechanical properties exhibited a diminishing trend with a higher MWCNT volume fraction. We conclude that the hybridization of CB and CNTs formed strong filler–filler networks in hybrid composites, consequently reinforcing the EPDM composites and enhancing the barrier properties of hydrogen gas.

The effects of octaphenylsilsesquioxane (OPS), fumed silica, and silica aerogel on the thermal insulation properties of ethylene propylene diene monomer (EPDM) rubber were studied. On this basis, two kinds of fillers with good performances were selected to study the thermal insulation of an EPDM full-formula system. The results show that the addition of fumed silica or silica aerogel had a positive effect on the thermal insulation performance of EPDM rubber and its composite. A 30 wt% silica aerogel can be well dispersed in the EPDM rubber system and with a lower thermal conductivity compared with fumed silica. EPDM composite with 23.4 wt% fumed silica can produce more char residues at 1000 °C than at 500 °C in a burn-through test and formed the compact and porous char at 1000 °C, which had a lowest thermal conductivity. EPDM composite with fumed silica cannot be burned through 1000 °C burning, and comparison with silica aerogel revealed that it achieved the lowest back temperature and had a temperature of 388 °C after 800 s.

Two-component (2K) injection molding of the combination of recycled polypropylene (rPP) and ethylene propylene diene monomer (EPDM) is very promising for automotive industry. Recently, the use of post-industrial wastes in the automotive industry became important in terms of reducing its environmental impacts and circular economy principles. In this study, the effect of processing parameters on the properties of rPP/EPDM deflector parts fabricated by means of a 2K injection molding process was investigated. Post-industrial waste PP was used in varying amounts (0%, 10% and 20% by weight) in rPP/EPDM parts. The properties of aged and unaged rPP/EPDM deflector parts were then compared. The effects of processing parameters on dimensional, mechanical, thermal, and morphological properties of rPP/EPDM parts were investigated by a coordinate measuring device (CMM), scanning electron microscope (SEM), tensile test, and differential scanning calorimetry (DSC) analysis. As a result of the CMM analysis, it was seen that the dimensional stability of the unaged parts was better than the aged parts. The adhesion between rPP and EPDM was found to be dependent on injection temperatures. [ABSTRACT FROM AUTHOR]

This research studies the effect of borax on the thermal stability and thermal kinetic behavior of ethylene-propylene-diene (EPDM) rubber composites. Using a laboratory two-roll mill at room temperature, carbon-black (N-220) as filler, and other additives such as zinc oxide, stearic acid, and paraffin oil were incorporated into the EPDM rubber matrix. The composite was prepared at different borax concentrations (25 and 50 phr). Thermogravimetric analysis was performed to characterize borax's effect onthermal stability before and after borax addition. Added borax to the host composite rubber (EPDM composite without borax) significantly improved the composite's thermal stability. Borax-loaded composites behave differently at various temperatures. To investigate the kineticthermal analysis of the prepared samples, three different models were applied. The activation energy (Ea) and frequency factors (A) for the Horowitz-Metzger, Broido and Coats-Redfern models were calculated. These models were compared and discussed based on their results. First-order decomposition also represented the main decomposition stage. Kraus and Cunnen-Russel models were used to test the interaction between rubber and borax based on previously published swelling results. No interaction was found between rubber and borax. [ABSTRACT FROM AUTHOR]

Modeling of complex systems requires large and expensive computational systems. Costs and processing time can be reduced by more than half in a well‐managed cloud environment. Modeling the flow of ethylene propylene diene monomer (EPDM) through a Garvey die was achieved by employing the latest cloud computer technology commercially available at a modest cost. The description of the stress–strain behavior for EPDM was done using the Otswald‐de Waele model. The results demonstrate that at higher velocities, the flow lines do not follow a smooth profile upon exiting the die, which indicates instabilities that may affect on the finished surface. Prediction of extrudate flow instabilities gives a computational option to make an initial estimate of permissible extrusion speeds. [ABSTRACT FROM AUTHOR]

This work focused studying waste car bumper samples and their processing by re‐extrusion‐injection. Car bumpers are composed of crystalline phases of polypropylene (PP), talc, and amorphous ethylene propylene diene monomer (EPDM). The recycled material's thermal, mechanical, and structural properties depend strongly on the process used for extrusion and injection and the crystalline phases formed during the heating process. The FWHM of the x‐ray diffraction patterns was used to study the recrystallization phenomenon in PP, and the result was in direct correlation with the Differential Scanning Calorimetry (DSC) results. The remaining micro paint particles from the bumpers involved in the recycled extrusion‐injection process affect the mechanical properties, and their size and toughness could affect the injection. Removing these particles could improve the mechanical properties of the recycled PP. Car parts based on polypropylene can be recycled for the automotive industry to produce the same type of products and even for other areas. A methodology and metrology can be developed to understand the chemical composition and its relationship with the properties of PP‐based materials. This could lead to finding new applications in different fields and promote the development of a circular economy. [ABSTRACT FROM AUTHOR]

This study examined the effects of lignin used in EPDM elastomer composites in place of carbon black. For that purpose, lignin was added in amounts of 3.5, 7, and 10.5 phr to investigate the chemical, thermal, rheological, mechanical, and morphological properties of the EPDM elastomers. At the end of the study, tear strength and elongation were enhanced, whereas thermal stability was lowered due to the lignin. The lignin facilitated the vulcanization process and improved the torque values. In the morphology, the lignin was dispersed homogeneously in the matrix, and no voids or cracks were observed except with 10.5 phr. In conclusion, when incorporated at a specified ratio, lignin is economical and provides ecological benefits. Its use as a natural filler can be recommended to automotive industries to provide enhanced properties and ecological properties as a substitute for carbon black.

The absorption of aroma compounds in seals during the bottling of wine and the migration of these aroma compounds into the subsequent bottling process is a major problem in the German wine industry. In order to meet the legal requirements, for example, the seals used up to now have to be replaced with more expensive alternatives. However, these alternatives are not suitable for every area of application. An alternative to this is the use of modified ethylene-propylene-diene-rubber seals, which have a lower aroma compound carry-over. In a research project, new and inexpensive ethylene-propylene-diene-rubber seals were developed which minimise migration into the subsequent filling process. The seal material and the surface of the seals were modified. Within the scope of the research, compounds of different fillers were prepared and examined for their migration properties of critical aroma compounds. Furthermore, the influence of the degree of crosslinking, the ethylene content of the basic rubbers used, the plasticisers used and the influence of the surface roughness of the seals were also examined. The seals were coated using low-pressure plasma in order to describe the migration of selected aroma compounds depending on the surface properties. In addition to the migration properties, the influence of the fillers used on mechanical properties such as elongation at break and compression set was also measured, since seals have to fulfil a wide range of requirements. By means of statistical test planning, the observation was carried out in effect and contour diagrams in order to create an optimised sealing material on the basis of the resources used.

Ground tire rubber (GTR) is a product obtained by grinding worn tire treads before retreading them or via the cryogenic or ambient temperature milling of end-of-life tires (ELTs). The aim of this study is to evaluate if calcium carbonate can be substituted by GTR and, if so, to what extent. Different types of ground tire rubber are incorporated in an EPDM (ethylene–propylene–diene–rubber) model compound as partial or complete substitutes of calcium carbonate. The raw compounds and the vulcanizates are characterized to identify the limits. In general, it is apparent that increasing amounts of GTR and larger particles degrade the mechanical properties. The GTR also influences the vulcanization kinetics by reducing the scorch time up to 50% and vulcanization time up to nearly 80%. This is significant for production processes. The compounds with one-third substitution with the smaller-particle-size GTR show mostly similar or even better properties than the reference. [ABSTRACT FROM AUTHOR]

Ethylene Propylene Diene Monomer (EPDM) rubber foams are widely employed for thermal and acoustic insulation in building construction. However, their installation in confined spaces is often complicated, and the capability of EPDM foams to exhibit shape memory behavior could be a desirable property. In the literature, several works have demonstrated that blending elastomeric matrices with paraffin, a well‐known Phase Change Material (PCM), could be an interesting method to obtain shape memory polymers with a tunable switching temperature. In this work, EPDM foams filled with paraffin wax, having a melting temperature of 70°C, were produced and characterized from a microstructural and thermo‐mechanical point of view. By melt compounding and hot pressing, samples were produced, and the PCM content in the foams was varied between 0 and 60 wt% (with respect to the EPDM matrix). The results of the shape memory tests evidenced the crucial role played by the PCM in providing excellent shape fixability for the expanded rubber. Even a limited amount of paraffin (i.e., 20 wt%) was able to raise the strain fixity parameter to a value higher than 80%, and it reached 100% when the paraffin content was increased to 60 wt%. On the other hand, an increased PCM fraction caused a slower recovery process. Consequently, a compromise between a fast recovery and optimum shape fixability should be accepted. These results are promising for the development of novel thermal and acoustic EPDM insulating foams easier to be installed. [ABSTRACT FROM AUTHOR]

During the COVID-19 pandemic, the use of face masks has been a worldwide primary protection measure to contain the spread of the virus. However, very little information is known about the possible inhalation of microplastics (MP) from wearing masks. This pilot study evaluates the presence of MP accumulated in nasal cavities through the nasal lavages technique. Six different commercial face masks were tested in 18 participants during five working days (8 h use/day). Eight different polymers (polystyrene, polyamide, poly(ethylene – propylene) diene monomer, polyester, polyethylene, polyvinylidene fluoride, polypropylene, and polyvinyl chloride) predominantly within the 20–300 µm size were detected in nasal lavages, with an average concentration of 28.3 ± 15.6 MP/5 mL nasal solution. Results demonstrate that MP in the nasal cavity are not associated to face mask use but rather to general exposure to airborne MP. We highlight the use of nasal lavages to evaluate human inhalation of MP and associate it to potential sources and risks.

Nonlinear electric conductance of reinforced insulation can homogenize electric field distribution and suppress local electric field distortion inside high-voltage direct current cable accessories. To achieve a significant nonlinear electric conductance in ethylene–propylene–diene misch–polymere (EPDM) used for reinforced insulation of cable accessories, the inorganic micron crystal powder of calcium copper titanate (CCTO) is synthesized by the sol–gel method, which is filled into EPDM to prepare 5∼15 wt% CCTO/EPDM composites by melting blend and hot-press molding methods. Microscopic structure, electric conductivity, direct current (DC) dielectric breakdown strength, and charge trap characteristics of CCTO/EPDM composites are tested to reveal the underlying derivation of electric conduction nonlinearity. Scanning electron microscopy and X-ray diffraction (XRD) demonstrate that CCTO micron fillers are uniformly dispersed in the EPDM matrix. Dielectric breakdown strength of CCTO/EPDM composites gradually decreases with the increase in CCTO content while persisting qualified for electrical insulation of DC cable accessories. CCTO crystal macron fillers introduce shallower charge traps than the intrinsic charge traps derived from the structural defect EPDM matrix, which initiates the percolating conductive channels between charge traps under high electric fields, accounting for the significant nonlinearity in the profile of electric current density versus electric field strength. Finite-element simulations and analyses on the electrostatic field in DC cable terminals prove that employing 15 wt% CCTO/EPDM composite as reinforced insulation can efficiently homogenize the electric field at the interface between the main insulation and accessory insulation of power cables, which is of great interest to develop insulation materials used for DC cable accessories in severe environments.

Accelerated thermal ageing (ATA) coupled to mechanical testing is widely used to predict the lifetime of polymeric products. ATA implies that the mechanisms of ageing are the same at accelerated and service conditions, which may often not be the case. Hence, ageing closer to service conditions is of high importance, but require very sensitive tools. Therefore, a high sensitivity microcalorimetry (MC) method was applied here to assess if it can be a possible tool for lifetime/ageing prediction closer to service conditions. We chose to focus on a complex, yet commonly used, ethylene-propylene-diene terpolymer (EPDM) rubber. Arrhenius extrapolation of the heat flow data indicated two regimes at low and high temperature, with the former having the lower activation energy. The heat flow values measured by the MC revealed contributions from processes such as the melting of the antioxidant, its consumption at low temperature and the breakdown of residual peroxide. MC tests on the EPDM indicated a very low degree of oxidation appearing above 100 °C, too low to be observed with infra-red spectroscopy (FTIR), but noticeable with MC. The high sensitivity of the MC techniques enabled detection of early signs of polymer degradation/ageing and other thermally activated processes that take place at or close to service temperatures (such as those in nuclear power plants). The MC tests were combined with other techniques, such as scanning electron microscopy/energy dispersive X-ray spectroscopy, gas chromatography techniques, differential scanning calorimetry and FTIR to further understand the degradation mechanisms.

Ethylene/propylene (E/P) and ethylene/propylene/5-ethylidene-2-norbornene (E/P/ENB) copolymers were obtained on rac-Et(2-MeInd)2ZrMe2 activated by a number of isobutylaluminium aryloxides: (2,6-tBu2PhO-)AliBu2 (1-DTBP) (2,6-tBu2,4-Me-PhO-)AliBu2 (1-BHT), (2,4,6-tBu2PhO-)AliBu2 (1-TTBP), (2,6-tBu2,4-Me-PhO-)2AliBu (2-BHT), (2,6-tBu2PhO-)2AliBu (2-DTBP), [(2-Me,6-tBu-C6H3O)AliBu2]2 (1-MTBP), [(2,6-Ph2-PhO)AliBu2]2 (1-DPP). This study shows how the structure of an activator influences catalytic activity and polymer properties, such as the copolymer composition, molecular weight characteristics, and thermophysical and mechanical properties. It has been shown that both the introduction of a bulky substituent in the para-position of the aryloxy group and the additional aryloxy group in the structure of an activator lead to a significant decrease in activity of the catalytic system in all studied copolymerization processes. Moreover, activation by bulkier aryloxides leads to lower levels of comonomer insertion and gives rise to higher molecular weight polymers. Broad or multiple endothermic peaks with different values of melting points are observed on the DSC curves of the copolymers obtained with different catalytic systems. The DSC of the thermally fractionated samples makes it possible to reveal the heterogeneity of the copolymer microstructure, which manifests itself in the presence of a set of lamellar crystallites of different thickness. The results also present the mechanical properties of the copolymers, such as the tensile strength (σ), elongation at break (ε), and engineering strain (EL). The synthesized E/P and E/P/ENB copolymers contain about 1–4 wt.% of the sterically hindered phenols obtained in situ as a residue of the hydrolyzed activators in the course of reaction quenching. This determines the increased thermooxidative stability of the copolymers. [ABSTRACT FROM AUTHOR]

As the requirements of aerospace technology become more rigorous, the performance of solid rocket motor (SRM) cases needs to be further optimized. In the present study, a co-curing technique was used to fabricate carbon fiber reinforced polymer (CFRP)/ethylene-propylene-diene monomer (EPDM) composites whereby the properties of CFRP/EPDM composites were adjusted by varying the temperature, heating time and type of vulcanizing agent to obtain the optimum manufacturing process. The results of crosslink density (3.459 × 10−4 mol/cm3) tested by nuclear magnetic resonance (NMR), a 90° peel strength test (2.342 N/mm), and an interlaminar shear test (ILSS = 82.08 MPa) demonstrated that the optimum mechanical properties of composites were obtained under the temperature 160 °C heated for 20 min with the curing agent DCP/S. The interfacial phase and bonding mechanism of composites were investigated by scanning electron microscopy (SEM). Thermogravimetric analysis (TGA) further indicated that EPDM/DCP/S had favorable thermal stability. This will provide valuable recommendations for the optimization of the SRM shell preparation process. [ABSTRACT FROM AUTHOR]

Polymeric insulators have lightweight, excellent hydrophobicity and convenient transportation and installation. They are widely used in the external insulation for distribution and transmission lines. However, due to the long-term effects of pollution, ultraviolet radiation, discharge, temperature, humidity, altitude and other natural and complex environmental and service factors, the silicone rubber and other materials of polymeric insulators gradually age and lose their hydrophobicity and electrical insulation characteristics. The operability is significantly reduced, which seriously affects the safety and reliability of the power system. Hence, there is a need for assessing and evaluating the long-term aging and degradation of polymeric insulators under various operating conditions and environments. In this review, the various aging and characterization techniques of the polymeric insulators and their aging performance under the action of multiple factors are discussed. To enhance the performance of polymeric insulators, nano-coating, surface treatment and other techniques are also indicated. In addition, future potential fields that should be explored from a high-voltage electrical insulation perspective are also presented. [ABSTRACT FROM AUTHOR]

Introduction. Water engineering facilities utilize geosynthetic barriers of various materials, but the most common are polyvinylchloride (PVC) and polyethylene (PE) considered to be the most efficient. However, the utilization of thermoset geosynthetics (PVC and PE) as watertight elements of the geosynthetic barriers of earth dams has also a number of drawbacks. In the course of time, PVC can lose its properties due to plasticizer loss, whereas PE is susceptible to cracking at thermal impacts. That is why it is necessary to consider geosynthetic barriers of other types as alternatives. For this purpose, we studied the deformability and the strength of geosynthetic barriers of thermoset material (chlorosulfonated polyethylene - CSPE), as well as of a rubber-type synthetic material (ethylene-propylene diene monomer - EPDM).Materials and methods. Sample testing of geosynthetic barrier materials for monoaxial extension was conducted by means of a tensile-testing machine, which records during the experiment the changes of the tensile force and the longitudinal extension. The changes of the cross-section area of the samples were measured by means of a digital side caliper.Results. It was determined that of the considered geosynthetic barrier types (PE, PVC, CSPE and EPDM) the strongest one is the reinforced CSPE type and the most deformable is the EPDM barrier. Reinforced CSPE geosynthetic barrier has a tensile strength above 100 MPa, it is approximately 5 times higher than that of PVC and PE barriers. By deformability, reinforced CSPE barrier is similar to PE barriers. An EPDM geosynthetic barrier has the linear deformation modulus around 1 MPa, it is capable of a multiple extension without loss of strength.Conclusions. By strength vs. deformability ratio, EPDM geosynthetic barriers can compete with PVC barriers.

This research aimed to investigate the water vapour transmission properties of chosen EPDM membranes applied in façade and window systems under laboratory tests. The applied procedure included in national and international standards utilized for the laboratory tests of water vapour transmission properties of EPDMmembrane is described. Two main types (outside and inside types) ofEPDMmembranes are laboratory tested. The authors indicated that the EPDM membranes should differ in surface factures. Nevertheless, some manufacturers mark EPDM membranes on each roll (on the package only) without different permanent denotations on the EPDM membranes surfaces. This form of denotations can cause using problems – using the wrong types of the EPDM aprons in building partitions, because when the package is removed there is impossible to visually identify the type of EPDM membrane (outside or inside type) from the texture of the membrane surface. The experimental results of laboratory tests indicated using the wrong type of EPDM membrane in the inside aprons in building partitions in the investigated façade window system. The designed proportion of the sd values (the resistance to movement of water vapour) of inside and out-side EPDM façade membranes should be designed equally to about 3.0 (recommended value 4) to provide proper diffusion properties of partitions around windows in façade systems. The paper can provide scientists, engineers, and designers an experimental basis in the field of the EPDM membranes water vapour transmission properties applied to façades and windows systems.

Devulcanization represents the recycling of choice for a homogenous rubber waste stream because it allows revulcanization of samples previously devulcanized, making the life of the rubber virtually endless, according to the principles of circular economy. Among the many devulcanization processes, the thermo-mechanical one is the most appealing because it is a continuous process, easy to be industrialized. In this paper a comprehensive set of analyses (FTIR, TGA, DSC, elemental analyses, Py-GC/MS, swelling tests) were carried out on a post-industrial ethylene propylene diene monomer (EPDM), thermo-mechanical devulcanized in a co-rotating twin-screw extruder with different process parameters (thermal and screw profile, rpm). Results of the swelling test according to the Flory–Rehner theory and Horikx analyses show that the higher the thermal profile and the higher the rpm, the higher is the percentage of devulcanization. The quality of the devulcanized sample in terms of sol fraction and percentage of random scissions depends on the process conditions. The screw profile concurs to the efficiency of the devulcanization: the different number of kneading elements and more in general the screw profile composition affects the percentage of devulcanization, making the results in some tests more dependent on the screw speed. [ABSTRACT FROM AUTHOR]

This study examined the effects of lignin used in EPDM elastomer composites in place of carbon black. For that purpose, lignin was added in amounts of 3.5, 7, and 10.5 phr to investigate the chemical, thermal, rheological, mechanical, and morphological properties of the EPDM elastomers. At the end of the study, tear strength and elongation were enhanced, whereas thermal stability was lowered due to the lignin. The lignin facilitated the vulcanization process and improved the torque values. In the morphology, the lignin was dispersed homogeneously in the matrix, and no voids or cracks were observed except with 10.5 phr. In conclusion, when incorporated at a specified ratio, lignin is economical and provides ecological benefits. Its use as a natural filler can be recommended to automotive industries to provide enhanced properties and ecological properties as a substitute for carbon black. [ABSTRACT FROM AUTHOR]

In this paper Ethylene Propylene Diene Monomer rubber (EPDM) foams were filled with different amounts of paraffin, a common phase change material (PCM) having a melting temperature at about 70 °C, to develop novel rubber foams with thermal energy storage (TES) capabilities. Samples were prepared by melt compounding and hot pressing, and the effects of three foaming methods were investigated. In particular, two series of samples were produced through conventional foaming techniques, involving physical (Micropearl® F82, MP, Lehvoss Italia s.r.l. Saronno, Italia) and chemical (Hostatron® P0168, H, Clariant GmbH, Ahrensburg, Germany) blowing agents, while the salt leaching method was adopted to produce another series of foams. Scanning electron microscopy (SEM) and density measurements showed that MP led to the formation of a closed-cell porosity, while a mixed closed-cell/open-cell morphology was detected for the H foamed samples. On the other hand, foams produced through salt leaching were mainly characterized by an open-cell porosity. The qualitative analysis of paraffin leakage revealed that at 90 °C only the foams produced through salt leaching suffered from significant PCM leakage. Consequently, the thermo-mechanical properties were investigated only in samples produced with H and MP. Differential Scanning Calorimetry (DSC) analysis revealed that EPDM/paraffin foams were endowed by good TES properties, especially at higher PCM contents (up to 145 J/g with a paraffin amount of 60 wt%). Tensile and compressive tests demonstrated the addition of the PCM increased the stiffness at 25 °C, while the opposite effect was observed above the melting temperature of paraffin. These results suggest that the EPDM foams produced with H and MP show an interesting potential for thermal management of electronic devices. [ABSTRACT FROM AUTHOR]

In this study, the effects of plastic deformation and failure of the folded part on the folding behavior of non‐crosslinked ethylene propylene diene terpolymer/paraffin oil/silica gel composites were investigated. The folding behavior was evaluated by the residual fold angle of a folded specimen; a lower fold angle indicates an enhanced folding performance. The fold angle decreased with increasing oil and silica content and was correlated with the tensile yield strain, which is generally related to plastic deformation. Furthermore, the test speed dependence of the fold angle for each set of oil contents and test temperatures was investigated. The fold angle decreased with a decrease in the test speed and an increase in the test temperature. Scanning electron microscopy revealed that the low‐fold angle, which indicates an improvement in the folding behavior, was caused by the destruction (voids, crazes, and cracks) of the folded part. [ABSTRACT FROM AUTHOR]

Aramid pulp (AP) is often used as a composite reinforcement due to its excellent properties, but poor dispersion and interfacial adhesion restrict its application in composite materials. In this work, tetraethyl orthosilicate (TEOS) was carried on the surface of AP by supercritical CO2 (scCO2) and hydrolyzed to synthesize the nano‐silica, which improves the dispersion of AP in ethylene‐propylene‐diene elastomer (EPDM). The nano‐silica particles were deposited on the AP surface, and th modified AP was evenly dispersed in the EPDM composites based on the SEM results. Moreover, a silane coupling agent (KH‐560) was brought by scCO2 to further modify the nano‐silica on the surface of the AP to improve the interfacial adhesion. Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy results show that after KH‐560 modification, active epoxy groups were introduced on the surface of AP. The tensile strength and tear strength of the KH‐560‐nano‐silica‐AP/EPDM composites were significantly improved, reaching 8.98 and 42.06 MPa, which increased by 26% and 88.10%, respectively, compared with untreated‐AP/EPDM composites. Dynamic mechanical analysis shows that the storage modulus of KH‐560‐nano‐silica‐AP/EPDM composites increased to 2456 MPa compared with the pure EPDM for 1873 MPa, and the loss factor decreased. When the AP was modified in scCO2 with nano‐silica and KH‐560, the composites' oil resistance was also improved. [ABSTRACT FROM AUTHOR]

Reciprocating friction and wear tests of the EPDM are carried out under various loads, and the composition of groups and compounds of EPDM before and after wear is revealed by FTIR and XRD. Then, the stick-slip behavior and wear resistance of EPDM under various loads are analyzed and investigated by real-time curves of the coefficient of friction, friction force, location and the change of friction force. Finally, the wear mechanism of EPDM under various loads is analyzed by the results of SEM. The results show that the stick-slip phenomenon occurs on the EPDM in different degrees under different loads. Neither the wear nor the change in load leads to the formation of new groups and compounds or the decomposition of existing groups and compounds in EPDM. The coefficient of friction does not change monotonically with increasing load, but tends to increase and then decrease. In addition, although the increase in load leads to increases in the lag time and the intensity of noise generated during the wear process, the rate of increase in the lag time and the intensity of noise slows down with increasing load. Meanwhile, with the increase in load, the number of granular debris changes, and banded debris and Schallamach waves become larger, which results in a change in the wear form between the grinding ball and EPDM.

Bottling of aromatised wines and regular table wines often takes place on the same bottling line. Installed sealings in the bottling line absorb volatiles from aromatised wines and, due to inadequate cleaning, carryover occurs into the subsequently bottled regular wine. This unintentional carryover can lead to accusations of illegal flavouring of wine. To minimise the carryover risk, sealing materials that absorb less volatiles are beneficial. Incorporating kaolin and micro-cellulose into the ethylene propylene diene monomer rubber (EPDM) network decreased absorption of the critical α-ionone by 51 and 60 %, respectively. Besides the minimisation of the absorption, a performed cleaning can reduce aroma carryover. So far, knowledge about cleaning parameters that can increase cleaning efficiency is limited since cleaning usually focuses on surficial removal and prevents microbiological cross-contamination. An evaluation of the cleaning parameters, temperature, time and agents clearly revealed a high factor in the considered temperature. The highest cleaning efficiency was seen at 85 °C, whereas the cleaning additives such as citric acid, caustic soda, ozone or dissolved carbon dioxide had no impact. High proportions of the aroma compounds were removed from the polymer in the first 20 min at 85 °C, but none of the performed cleaning sequences was able to remove all compounds.

This study investigates the use of eddy-current technology and impedance spectroscopy in sensing the change in rubber properties after it is exposed to accelerated thermal aging. The thermal aging process, by application of temperature and pressure over time, of ethylene propylene diene monomer (EPDM) rubbers containing both carbon black (CB) and graphene are investigated. Both eddy-current sensing and electrical impedance measurement techniques were used for electromagnetic analysis. Both methods measure the in- and out-of-phase responses as a function of excitation frequency at room temperature. The measurements were performed before and after the aging process. The electrical percolation threshold was detected in the rubber samples by varying the CB content from 0 to 40 wt%. In the rubber sample containing 30 wt% CB, 0–5 wt% of the CB was replaced with graphene flakes. The substitution of graphene for CB in the EPDM rubber formulation provided an enhanced eddy-current and electrical impedance response. The findings demonstrate the feasibility of employing electromagnetic analysis techniques to investigate the extent of aging.

Ethylene-propylene-diene rubbers (EPDM) are one of the most important polyolefin materials widely commercialized and used in various industries in recent years. The production of EPDM is based solely on catalytic coordination polymerization processes. The development of new catalysts and processes for the synthesis of EPDM has expanded the range of products and their manufacturing in terms of energy efficiency, processability, and environmental safety. This mini-review mainly analyzes patented data on the synthesis of EPDM on new-generation single-site catalytic systems based on Group IVB complexes including the systems commercialized by major manufacturers of EPDM. The advantages of these systems are evident in comparison with conventional vanadium systems introduced into production in the 1960s and used to date in the industrial synthesis of EPDM. [ABSTRACT FROM AUTHOR]