EPDM Research Articles

Innovative strategy for the facile construction of active multifunctional coating on inert thermal insulation surface

Ethylene propylene diene monomer rubber is highly attractive as a thermal insulation material for solid rocket motors but is plagued by its inherent low wettability. Existing methods have been used to solve this problem by manually or mechanically sanding the surface, which is environmentally hazardous. Herein, a multifunctional composite coating is constructed on the surface of inert thermal insulation materials using a two-step low temperature plasma surface treatment via an efficient hydrogen-bonding assembly strategy. The resultant composite coating exhibits excellent adhesion to the inert thermal insulation substrate. Benefitting from this, the coating retained its superhydrophilicity after 80 abrasion cycles and 12 h of agitation scrubbing with saturated salt water. Due to the superhydrophilicity of the coating, a self-cleaning effect for oils of different viscosities on the surface can be achieved by the simple action of water. Besides the adiabatic performance tests showed that the average top surface temperature of the coated thermal insulation was 30.9 °C lower than that of the original thermal insulation. Char residue analysis showed that the coating formed a more complete char layer at high temperatures, resulting in improved adiabatic performance. Our work would afford a new frontier to fabricate solid rocket motor thermal insulation materials with excellent surface comprehensive properties in a simple, eco-friendly and sustainable way, opening new possibilities for the advancement of high-performance inert materials.

XGBoost machine learning assisted prediction of the mechanical and fracture properties of unvulcanized and dynamically vulcanized PP/EPDM reinforced with clay and halloysite nanoparticles

AbstractPolymer nanocomposites have found wide industrial applications, necessitating optimal mechanical and fracture properties evaluation, traditionally done through costly experimental methods. This study employs machine learning, particularly XGBoost, to predict properties like tensile and fracture properties swiftly, aiding material innovation across industries. The research investigates unvulcanized and vulcanized polypropylene (PP)/ethylene propylene diene monomer (EPDM) reinforced with clay and halloysite nanoparticles (HNT), analyzing fracture properties via essential work of fracture (EWF). Experimental design selects tests, and an XGBoost model predicts tensile strength and modulus, strain at break, EWF, and non‐EWF based on EPDM and nanoparticle percentages, composite and nanoparticle types. The model accurately predicts tensile strength and modulus but less so for strain at break, EWF, and non‐EWF. Mean Absolute Percentage Error values for training/test are 0.49/1.21, 1.05/1.55, 34.21/42.76, 3.02/14.35, and 2.89/3.78, with determination coefficients of 0.99/0.98, 0.99/0.97, 0.97/0.91, 0.97/0.79, and 0.92/0.73. Nanoparticles mainly affect outputs, with EPDM secondarily impactful, while composite and nanoparticle types exhibit similar significance. The best‐performing polymer nanocomposite is a dynamically vulcanized one containing 10 wt% EPDM and 3 wt% clay, achieving tensile strength of 25.070 MPa, tensile modulus of 261.170 MPa, EWF of 75.300 N/mm, and non‐EWF of 10.150 N/mm2.Highlights The effects of ethylene propylene diene monomer (EPDM), clay and halloysite nanoparticles on the mechanics of polypropylene‐based nanocomposites. Essential work of fracture (EWF) was used to study the fracture properties. Machine learning was employed to predict all mechanical characteristics. The vulcanization process improved all mechanical characteristics. The best compound: vulcanized one containing 10 wt% EPDM and 3 wt% clay.

Exploring Green Route of Cross-Linking for Bio-Based Ethylene Propylene Diene Rubber: A Step toward Circular Economy

Exploring Green Route of Cross-Linking for Bio-Based Ethylene Propylene Diene Rubber: A Step toward Circular Economy

Surface‐modified graphite based polymer nanocomposites for high‐temperature geothermal applications

AbstractThis research aims to develop novel economical and thermally‐stable polymer nanocomposites to seal geothermal wells by dispersing surface‐modified graphite into an inexpensive raw polymer. Using a mixture of nitric acid and sulfuric acid, a nano‐scale graphite filler, namely small‐size lamellar graphite (SFG15), was surface‐modified, which introduced considerable oxygen and carboxylic (COOH) groups to graphite surfaces, as verified by X‐ray photoelectron spectroscopy (XPS) analysis. Polymer nanocomposites were fabricated by dispersing different concentrations of modified graphite SFG15, including 1.5, 3, 6, and 9 wt%, into the ethylene propylene diene monomer (EPDM) matrix. First, characterization techniques, including wide‐angle X‐ray scattering (WAXS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), were employed to examine modified graphite dispersion in the nanocomposites. Then, dynamic mechanical analysis (DMA), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA) were used to quantitatively study the key mechanical and thermal properties of the nanocomposites. It was found that introducing modified SFG15 to EPDM enhances its resistance to deformation at high temperatures significantly. Notably, 9 wt% of modified SFG15 showed superior performances in improving the storage modulus of EPDM by 191.17%, enhancing loss modulus by as high as 136.08%, and decreasing tan by 18.93%. After introducing modified graphite, the energy needed for melting EPDM was increased markedly, which was accompanied by improvement in its heat capacity. Compared with pure EPDM, the onset temperature of degradation for developed nanocomposites could be increased by over , and the temperature of 50% degradation was raised by up to . Possessing the improved mechanical and thermal performances, the nanocomposites developed could be a primary choice for materials used to seal geothermal wells.Highlights A technique is developed to reinforce low‐cost polymers for high‐temperature use. Reinforcement of EPDM with high concentrations of modified graphite is investigated. Modified graphite increases the high‐temperature storage modulus of EPDM by 191.17%. Degradation temperatures of EPDM are enhanced by modified graphite considerably. Low‐cost polymer composites are essential seals for application in deep geothermal wells.

Highly toughened PP/Rice husk charcoal composites modified Ethylene Propylene Diene Monomer (EPDM) with glycidyl methacrylate

Highly toughened PP/Rice husk charcoal composites modified Ethylene Propylene Diene Monomer (EPDM) with glycidyl methacrylate

Fe3O4 Nanoparticles Embedded into Pyridinic-N-Rich Carbon Nanohoneycomb with Strong dx2-Pz Orbital Hybridization for High-Performance Electromagnetic Wave Absorption.

Carbon-based magnetic nanocomposites as promising lightweight electromagnetic wave (EMW) absorbents are expected to address critical issues caused by electromagnetic pollution. Herein, Fe3O4 nanoparticles embedded into a 3D N-rich porous carbon nanohoneycomb (Fe3O4@NC) were developed via the pyrolysis of an in-situ-polymerized compound of m-phenylenediamine initiated by FeCl2 in the presence of NaCl crystals as templates. Results demonstrate that Fe3O4@NC features highly dispersed Fe3O4 nanoparticles into an ultrahigh specific pyridinic-N doping carbon matrix, resulting in excellent impedance matching characteristics and electromagnetic wave absorbing capability with the biggest effective absorption bandwidth (EAB) of up to 7.1 GHz and the minimum reflective loss (RLmin) of up to -65.5 dB in the thin thickness of 2.5 and 2.3 mm, respectively, which also outperforms the majority of carbon-based absorbers reported. Meanwhile, its high absorption performance is further demonstrated by an ethylene propylene diene monomer wave absorbing patch filled with 8.0 wt % Fe3O4@NC, which can completely shield a 5G signal in a mobile phone. In addition, theory calculation reveals that there is a strongest dx2-Pz orbital hybridization interaction between Fe3O4 clusters and pyridinic-N dopants in the carbon network, compared with other kinds of N dopants, which can not only generate more dipoles of carbon networks but also increase net magnetic moments of Fe3O4, thereby leading to a coupling effect of efficient dielectric and magnetic losses. This work provides new insights into the precise design and synthesis of carbon-based magnetic composites with specific interface interactions and morphological effects for high-efficiency EMW absorption materials.

Real-time temperature control in rubber extrusion lines: a neural network approach

In rubber extrusion, precise temperature control is critical due to the process’s sensitivity to fluctuating parameters like compound behavior and batch-specific material variations. Rapid adjustments to temperature deviations are essential to ensure stable throughput and extrudate surface integrity. Based on our previous research, which initiated the development of a feedforward neural network (FNN) without real-world empirical application, we now present a real-time control system using artificial neural networks (ANNs) for dynamic temperature regulation. The underlying FNN was trained on a dataset comprising different ethylene propylene diene monomer (EPDM) rubber compounds, totaling 14,923 measurement points for each temperature value. After training, the FNN achieves remarkable precision, evidenced by a mean absolute percentage error (MAPE) of 0.68% and a mean squared error (MSE) of 0.63°C2 in predicting temperature variations. Its integration into the control system enables real-time responsiveness, allowing for adjustments to temperature deviations within an average timeframe of 68 ms. A key advantage over proportional-integral-derivative (PID) controllers is the ability to continuously learn and adjust to complex, non-linear, and batch-specific process dynamics. This adaptability results in enhanced process stability, as evidenced by inline manufacturing validation. Our paper presents the first ANN-based rubber extrusion control, demonstrating how machine learning techniques can be effectively leveraged for real-time, adaptive temperature control. Beyond rubber extrusion, this strategy has potential applications in various polymer processing and other industries requiring precise temperature control. Future trends may involve the integration of online learning techniques and the expansion of interconnected manufacturing processes.

Mooney-Rivlin Parameter Determination Model as a Function of Temperature in Vulcanized Rubber Based on Molecular Dynamics Simulations.

The automotive industry is entering a digital revolution, driven by the need to develop new products in less time that are high-quality and environmentally friendly. A proper manufacturing process influences the performance of the door grommet during its lifetime. In this work, uniaxial tensile tests based on molecular dynamics simulations have been performed on an ethylene-propylene-diene monomer (EPDM) material to investigate the effect of the crosslink density and its variation with temperature. The Mooney-Rivlin (MR) model is used to fit the results of molecular dynamics (MD) simulations in this paper and an exponential-type model is proposed to calculate the parameters C1(T) and C2T. The experimental results, confirmed by hardness tests of the cured part according to ASTM 1415-88, show that the free volume fraction and the crosslink density have a significant effect on the stiffness of the EPDM material in a deformed state. The results of molecular dynamics superposition on the MR model agree reasonably well with the macroscopically observed mechanical behavior and tensile stress of the EPDM at the molecular level. This work allows the accurate characterization of the stress-strain behavior of rubber-like materials subjected to deformation and can provide valuable information for their widespread application in the injection molding industry.

Vat photopolymerization of olefinic elastomers from sulfonated ethylene-propylene-diene monomer (EPDM) latexes

Ethylene-Propylene-Diene Monomer (EPDM) rubber is recognized for elasticity over a wide temperature range and exceptional resistance to UV light and oxidative degradation. In this study, sulfonated EPDM (sEPDM) latex serves as an innovative platform for 3D printing olefinic elastomers through vat photopolymerization (VPP). The sulfonation of EPDM and subsequent neutralization with potassium hydroxide enabled the production of water-dispersible sEPDM (K-sEPDM), yielding a stable latex with an average particle diameter of 125 nm. The inherent low viscosity of the latexes allowed the direct application of elastomeric polymers during the VPP process. The photopolymerization of a scaffold precursor composition, which consisted of n-vinylpyrrolidone (NVP) and poly(ethylene glycol) diacrylate (PEGDA) in the aqueous phase of K-sEPDM latex, solidified the latex as a particle embedded hydrogel. Post-processing for removing water from the 3D printed green body facilitated coalescence of the K-sEPDM particles throughout the scaffold network, generating a second ionically crosslinked network together with scaffold as an interpenetrating polymer network (IPN). Tensile testing demonstrated tunable elastomeric properties with an ultimate strain from 315±11–453±37 % and ultimate stress from 7.6±0.5–8.2±0.3 MPa with excellent thermal recoverability. VPP of photocurable K-sEPDM with a commercial printer showcased high-resolution printing capabilities with controllable isotropic shrinkage for the printing of olefinic elastomers.

Effect of Hydrogen Pressure on the Fretting Behavior of Rubber Materials

Safety and reliability are the major challenges to face for the development and acceptance of hydrogen technology. It is therefore crucial to deeply study material compatibility, in particular for tribological components that are directly in contact with hydrogen. Some of the most critical parts are sealing materials that need increased safety requirements. In this study, the fretting behavior of several elastomer materials were evaluated against 316L stainless steel in an air and hydrogen environment up to 10 MPa. Several grades of cross-linked hydrogenated acrylonitrile butadiene (HNBR), acrylonitrile butadiene (NBR) and ethylene propylene diene monomer rubbers (EPDM) were investigated. Furthermore, aging experiments were conducted for 7 days under static conditions in 100 MPa of hydrogen followed by rapid gas decompression. Fretting tests revealed that the wear of these compounds is significantly affected by the hydrogen environment compared to air, especially with NBR grades. After the aging experiment, the friction response of the HNBR grades is characterized by increased adhesion due to elastic deformation, leading to partial slip.

A Review of EPDM (Ethylene Propylene Diene Monomer) Rubber-Based Nanocomposites: Properties and Progress.

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.

The Effect of Different Accelerators on the Vulcanization of EPDM Rubber

: EPDM (ethylene propylene diene monomer) is a type of synthetic rubber. The products of rubber have great importance in every part of life. EPDM rubber has high tensile strength, high tension, toughness, and is weather resistant. Therefore, EPDM (ethylene-propylene-diene rubber) is widely used in many fields. The aim of this study is to examine the effect of accelerator type on mechanical properties and vulcanization characteristics of EPDM rubber. We used the accelerators; thiazole, sulfonamides, dithiocarbamate, thiuram, and guanidine groups. The results show that the fastest cure time and the best tensile strength are achieved with dithiocarbamates for EPDM rubber.

Use of expanded perlite as green filler for the preparation of EPDM‐perlite rubber composites with improved thermal stability and insulation properties

AbstractThe present study investigated the use of expanded perlite (e‐perlite) as a sustainable and cost‐effective filler for EPDM (ethylene propylene diene monomer) rubber composites. Various amounts of e‐perlite were incorporated into EPDM to assess its impact on the composite properties, such as curing characteristics, physical and mechanical properties, crosslink density, thermal conductivity, thermal stability, surface roughness, and contact angle. The composite with 15 phr of e‐perlite exhibited approximately 20% higher crosslink density and a 12% increase in hardness, while slight decreases were observed in elongation at break and tensile strength. The FE‐SEM (field emission‐scanning electron microscopy), atomic force microscopy, and contact angle analysis have been performed to investigate the surface morphology and the hydrophobicity. The thermal properties of the composites were assessed through thermogravimetric analysis, thermal aging tests, and thermal conductivity measurements. The results showed that e‐perlite significantly improved the aging resistance and the thermal stability. The composites with 15 phr e‐perlite exhibited a 21% reduction in thermal conductivity and enhanced thermal isolation properties compared to the EPDM composite without e‐perlite. This work demonstrated the potential utilization of e‐perlite in EPDM as a green sustainable filler to enhance the thermal insulation and the stability properties of the composites, which may have practical applications in automotive, aerospace, construction, and electronic industries.Highlights E‐perlite enhances the thermal insulation property of EPDM rubber composites. Higher e‐perlite content increases composite hardness and crosslink density. The thermal conductivity of EPDM is reduced by increasing e‐perlite content. EPDM/e‐perlite exhibits improved thermal stability and aging resistance. Potential uses in automotive, aerospace, construction, and defense industries.

Preparation of ablation-resistant ethylene propylene trioxide/polyimide staple fiber composite insulation layer by solution wet mixing process

This research developed a solution wet mixing process for creating Ethylene propylene diene monomer/polyimide staple fiber composites (EPDM/PISF), overcoming the uneven fiber distribution seen in traditional dry mixing techniques. By uniformly dispersing PISF within the EPDM matrix, the wet mixing process improves the composite's performance. This is evidenced by an 18.08 % reduction in ΔG′, a 14.29 % lower linear ablation rate (0.042 mm/s), enhanced thermal stability, a higher charring rate, and a denser carbonized layer. Optimal overall performance was achieved using a PISF content of 10phr in the wet mixing process. This advancement significantly enhances the ablation resistance of EPDM/PIS, making them a promising choice for high-performance and durable insulation in solid rocket motors.

Advanced Recycling of Modified EDPM Rubber in Bituminous Asphalt Paving

One of the environmental problems worldwide is the enormous number of surgical masks used during the COVID-19 pandemic due to the measures imposed by the World Health Organization on the mandatory use of masks in public spaces. The current study is a potential circular economy approach to recycling the surgical masks discarded into the environment during the COVID-19 pandemic for use in bituminous asphalt pavement. FTIR analysis showed that the surgical masks used were made from ethylene propylene diene monomer (EPDM) rubber modified with polypropylene. The effects of the addition of surgical masks in bituminous asphalt on the performance of the base course were demonstrated in this study. The morphology and elemental composition of the bituminous asphalt pavement samples with two ratios of surgical mask composition were investigated by SEM-EDX and the performance of the modified bituminous asphalt pavement was determined by Marshall stability, flow rate, solid–liquid ratio, apparent density, and water absorption. The study refers to the technological innovation of using surgical masks in the formulation of AB 31.5 bituminous asphalt base course, which brings tremendous benefits to the environment by reducing the damage caused by the COVID-19 pandemic.

Development of halloysite nanotubes reinforced chlorinated ethylene propylene diene monomer/chlorinated acrylonitrile butadiene rubber blends

Development of halloysite nanotubes reinforced chlorinated ethylene propylene diene monomer/chlorinated acrylonitrile butadiene rubber blends

Effect of lignin on the structure-property behavior of metal-coordinated and chemically crosslinked ethylene-propylene-diene-monomer composites

The efficient development and utilization of green biomass-based macromolecule engineering materials are essential for the sustainable development of human civilization. In this study, lignin-based ethylene-propylene-diene-monomer (EPDM) composites with excellent mechanical performance were fabricated using a simple method. The effects of water-insoluble enzymatically hydrolyzed lignin (EL) and alkali lignin (KL) on the mechanical performance of the composites were investigated separately. The results showed that the tensile strength of EPDM reinforced with KL and EL increased to 24.5 MPa and 22.1 MPa, respectively, surpassing that of the carbon black (CB)-reinforced EPDM. After 72 h of thermo-oxidative aging, the retention rates of the tensile strength and elongation at break in the lignin-reinforced EPDM were much better than those formed with pure CB, indicating that lignin significantly improved the thermo-oxidative aging resistance of the composites. In summary, the Zn2+ coordination bonds formed between the interface of EPDM and lignin in lignin/CB/EPDM ternary composites effectively improved the mechanical performance and aging resistance of the composites. This study has significant implications for enhancing the utilization of lignin and green functional polymer materials.

The effect of 1,3-(bis citraconimidomethyl)Benzene on the reversion of cured ethylene-propylene-diene monomer (EPDM) rubber using semi-efficient vulcanisation (SEV) system and a nano zinc oxide as an activator

This study presents a comprehensive analysis of the impact of the anti-reversion agent, 3-(bis citraconimidomethyl) Benzene, Perkalink 900, on the properties, with a focus on reversion tendencies, of carbon black-filled ethylene-propylene-diene monomer (EPDM) rubber compounds cured using a semi-efficient vulcanization (SEV) sulfur curing system with various accelerators. The research highlights that the presence of Perkalink 900 significantly prolongs the optimum cure times for all rubber compounds, reducing ∆torques, especially in fast-curing systems. Crosslink density (CLD) exhibits minimal sensitivity to Perkalink 900, which effectively prevents reversion, even reaching zero in certain compounds. Reversion extent varies with the chosen curing system, and the concentration of Perkalink 900 plays a key role in its control. Perkalink 900 enhances Shore A hardness, indicating a denser and stiffer rubber, while tear strength and elongation at break improve. Tensile strength remains stable or slightly increases, and the modulus response varies based on the curing agent and Perkalink 900 loading. ATR-FTIR spectra confirm Perkalink 900 presence, with peak intensities correlating with its concentration. Additionally, a new Alder-ene reaction mechanism between EPDM and Perkalink 900 is proposed. Overall, the study establishes Perkalink 900 as an effective anti-reversion agent, proving its potential to significantly enhance rubber compound properties. Future investigations could focus on optimizing Perkalink 900 concentrations for specific applications and exploring its interactions with diverse rubber types and curing systems.

Impact of surface topography and hydrodynamic flow conditions on single and multispecies biofilm formation by Escherichia coli O157:H7 and Listeria monocytogenes in presence of promotor bacteria

Biofilm formation of E. coli O157:H7 and L. monocytogenes in the presence of promotor bacteria R. insidiosa was evaluated on equipment surfaces under different hydrodynamic flow conditions in a Centers for Disease Control and Prevention biofilm reactor (CBR). The CBR containing 330 ml bacterial suspension (6 log CFU/ml in 10% TSB) was used to grow the biofilms on SS 316 L, PTFE, Polycarbonate and EPDM rubber surface coupons under 100, 200 and 300 rpm (shear stresses 0.368, 1.218 and 2.462 N/m2, respectively) for 24 h in batch flow and additional 24 h in continuous flow conditions. Surface roughness and topography of coupons were measured by electron microscopy. Bacterial populations in biofilms were determined by scrapping of coupon surfaces and plating on selective media. Multispecies E. coli O157:H7 biofilm formations were affected by the surface and shear stress. SS, PTFE, and PC exhibited a significant increased biofilm growth at higher shear stress of 2.462 N/m2 compared to 0.368 N/m2. Multispecies L. monocytogenes biofilms formation decreased with increasing shear stress on all the surface materials. Our study emphasizes the importance of surface skewness and kurtosis besides surface's roughness while selecting the material for food processing environments.

A general hyperelastic model for rubber-like materials incorporating strain-rate and temperature

A comprehensive hyperelastic model that precisely forecasts the mechanical characteristics of materials with rubber-like qualities is presented. This model relies on the well-established five-parameter Mooney-Rivlin model, which is then extended to incorporate strain rate dependent and temperature dependent term. To validate its accuracy, experimental data from ethylene propylene diene monomer (EPDM) rubber materials was utilized to compare with the model prediction. Hyperelastic stress-strain curves were collected from a variety of materials that were subjected to varying temperatures and strain rates to improve the model’s applicability. Its prediction results are compared against the collected experimental data, resulting in consistent and reliable outcomes. The simplified form of the model not only establishes an effective framework for characterizing and predicting the mechanical response of materials that resemble rubber under different working conditions but makes the coding and implementation of finite element analysis easier.