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Compression set

Compression set is a key mechanical property of elastomeric materials, such as rubber, that quantifies the permanent deformation remaining after the material has been compressed under specified conditions of force, time, and temperature, and then allowed to recover.^[1] This property assesses the material's ability to return to its original shape and thickness, with lower compression set values indicating better elastic recovery and long-term performance under sustained loads.^[2] It is particularly critical for applications involving seals, gaskets, and O-rings, where incomplete recovery can lead to leakage or failure in dynamic or static environments.^[3] The standard method for evaluating compression set is outlined in ASTM D395, which includes procedures like Method B for constant deflection testing, where a cylindrical or button-shaped specimen is compressed to 25% of its original thickness for durations such as 22 hours at elevated temperatures (e.g., 70°C for general-purpose rubbers), followed by measurement of the residual thickness after a recovery period.^[1] Compression set percentage is calculated as the ratio of the deformation to the original deflection, typically expressed as a value between 0% (perfect recovery) and 100% (no recovery), with values under 20-30% considered favorable for most sealing applications depending on the elastomer type.^[4] Alternative standards, such as ISO 815, provide similar guidelines but may vary in specimen preparation or testing conditions to account for specific industry needs.^[5] Several factors influence compression set, including the polymer chemistry (e.g., natural rubber exhibits higher set than fluor elastomers), degree of crosslinking during vulcanization, fillers, and environmental exposures like heat or chemicals, which can accelerate stress relaxation and creep.^[6] Materials with low compression set, such as silicone or EPDM rubbers when properly formulated and post-cured, are preferred in demanding sectors like automotive, aerospace, and medical devices to ensure durability and sealing integrity over extended service life.^[7] High compression set, conversely, may suit short-term or low-stress uses but risks dimensional instability in prolonged applications.^[8]

Definition and Fundamentals

Definition

Compression set is the permanent deformation or residual strain that remains in a material, typically elastomers, rubbers, foams, or polymers, after it has been subjected to compression under specified conditions and then allowed to recover.^[1] This phenomenon indicates the material's inability to fully return to its original shape and dimensions following the release of the compressive force.^[9] Quantitatively, compression set is expressed as the percentage of the original deformation that is not recovered, with values ranging from 0% for perfect elastic recovery to 100% for complete lack of recovery.^[8] Low compression set values signify materials with superior elastic properties, essential for applications requiring sustained sealing or cushioning performance.^[4] The term and standardized measurement of compression set originated in the 1930s through early rubber testing protocols, gaining prominence in the mid-20th century alongside the rapid development of synthetic rubbers during World War II for critical sealing applications.^[10]^[11] At its core, compression set arises from the viscoelastic nature of polymers, where materials exhibit both elastic (instantaneous recovery) and viscous (time-dependent flow) behaviors, leading to hysteresis—or energy dissipation during deformation cycles—that prevents full rebound.^[12] This incomplete recovery is a fundamental characteristic in polymer science, distinguishing viscoelastic materials from ideal elastomers.^[13] The property is commonly evaluated using standards such as ASTM D395, which assesses recovery under controlled compression.^[1]

Underlying Mechanisms

At the molecular level, compression set in elastomers arises from the rearrangement of polymer chains under applied stress, where the chains adopt more ordered configurations during deformation. Upon release, full recovery is often impeded by several processes, including viscoelastic relaxation, which involves the gradual dissipation of stored energy through chain segment movements; crystallization, where aligned chains form ordered crystalline regions that resist recoiling; and cross-link breakdown, particularly under high stress or incomplete curing, leading to permanent alterations in the network structure.^[2] These mechanisms collectively contribute to incomplete elastic rebound, transforming temporary deformation into residual strain. The elasticity of rubbers is fundamentally entropic, relying on the tendency of polymer chains to return to a high-entropy, disordered state after deformation, driven by thermal motion that favors random conformations over aligned ones. However, during prolonged compression, this entropic recovery is compromised by energy dissipation through internal friction and viscous flow within the polymer matrix, resulting in a loss of configurational entropy that manifests as permanent deformation.^[14]^[15] Deformation in elastomers can be decomposed into elastic (reversible) and plastic (irreversible) components, with compression set serving as a quantitative measure of the plastic portion that remains after unloading. The elastic component allows instantaneous recovery via entropic forces, whereas the plastic component accumulates due to irreversible chain slippage, cross-link scission, or filler-induced restrictions on mobility.^[2] The time-dependent nature of these processes is captured by viscoelastic models, such as the Maxwell model, which represents the material as a spring (elastic modulus E) and dashpot (viscosity \eta) in series. In this framework, the relaxation time \tau = \eta / E governs the rate at which stress decays under constant strain, with longer \tau values indicating slower recovery and higher susceptibility to compression set.^[16] This model highlights how viscoelasticity bridges ideal elasticity and viscous flow, explaining the gradual onset of permanent deformation in real elastomers.

Importance in Materials Engineering

Compression set plays a pivotal role in ensuring product reliability within materials engineering, particularly for elastomeric components subjected to prolonged static loads. High compression set results in permanent deformation that compromises the functionality of seals, gaskets, and cushions, leading to leaks, loss of sealing pressure, and eventual system failure over time.^[8] This deformation prevents materials from returning to their original shape, thereby undermining the elastic recovery necessary to maintain continuous contact and prevent fluid or gas ingress in critical assemblies.^[14] In industry standards, acceptable compression set values are generally below 25% for many applications to ensure long-term durability, with values under 10% preferred for critical high-performance seals, while levels exceeding 50% signal inadequate material suitability for load-bearing roles.^[17]^[2] These thresholds, often evaluated through brief references to ASTM D395 testing methods, guide material selection to meet reliability demands in engineering design.^[2] Low compression set is especially vital in static load scenarios, where near-complete recovery is required to sustain performance without ongoing deformation, contrasting with dynamic applications that may accommodate higher set values due to cyclic motion aiding repositioning.^[18] The economic implications of poor compression set are significant, as it contributes to premature component failure, operational downtime, and potential product recalls, thereby increasing maintenance costs and reducing service life.^[19] For instance, in O-ring applications critical to aerospace systems since the mid-1950s, suboptimal compression set resistance has historically amplified risks of seal degradation, escalating repair and replacement expenses in high-stakes environments.^[20] By prioritizing materials with superior compression set performance, engineers mitigate these financial burdens and enhance overall system longevity.^[21]

Measurement Methods

Compression Set A

Compression Set A refers to the standard test method for measuring the compression set of rubber compounds under constant force in air, as outlined in ASTM D395. This method simulates scenarios where elastomeric materials are subjected to sustained compressive loads, such as in seals or mounts, allowing the material to deform variably under a fixed force. The test evaluates the material's ability to recover its original thickness after prolonged compression, providing insight into its long-term elastic performance in atmospheric environments.^[22] The procedure begins with preparing a cylindrical specimen, typically 29 mm in diameter and 12.7 mm thick, cut from a molded rubber sheet or directly molded to these dimensions. The initial thickness of the specimen, denoted as t_0, is measured precisely using a micrometer or similar device. The specimen is then placed between parallel platens in a compression rig equipped with a loading mechanism, such as a bolt and nut system or calibrated weights, to apply a constant compressive force of 1.8 kN (approximately 400 lbf), which generally results in about 25% deflection for standard rubber compounds. No spacers are used, as the method maintains constant force rather than fixed deflection, allowing the specimen to compress as needed under the load.^[23]^[24] Test conditions (time and temperature) are selected based on the material and application, with common values for general-purpose rubbers being 70°C for 22 hours, though variations up to 70 hours or higher temperatures may be used depending on requirements. This exposure occurs in air, making the test suitable for materials intended for atmospheric service and unsuitable for liquid immersion scenarios. After the compression period, the assembly is removed from the oven, the load is carefully released to avoid additional deformation, and the specimen is allowed to recover for 30 minutes at room temperature (typically 23°C ± 2°C). The final thickness, t_i, is then measured under no load.^[22]^[23]^[25] The compression set percentage is subsequently calculated based on the change in thickness, with the specific formula provided in the Calculation Formulas section. This method's use of constant force distinguishes it from deflection-controlled tests, emphasizing load-bearing behavior in real-world applications.^[22]

Compression Set B

Compression set B refers to the constant deflection method used to evaluate the elastic recovery of rubber and elastomeric materials after prolonged compressive strain, as defined in ASTM D395 Method B.^[1] In this procedure, a cylindrical specimen—typically either 12.7 mm thick and 29 mm in diameter (Type 1) or 6.4 mm thick and 13 mm in diameter (Type 2)—is compressed to a fixed deflection, usually 25% of its original thickness, though ranges of 25-75% may be applied depending on the material.^[4] The compression is achieved by placing the specimen between parallel plates separated by precisely machined spacers that maintain the constant strain throughout the test.^[26] This method applies a fixed strain to simulate real-world conditions where materials experience sustained deformation without varying load, contrasting with force-based approaches that allow strain to fluctuate.^[1] The test is conducted in air within a controlled environment, such as an oven. Test conditions (time and temperature) are selected based on the material and application, typically 22 hours at 70°C for general-purpose rubbers, though longer periods like 70 hours or higher temperatures (e.g., 100°C) may be used for specialized evaluations.^[4] Assembly of the specimen into the compression device must occur within two hours prior to exposure to ensure consistent starting conditions.^[4] The equipment primarily consists of a compression jig or fixture designed to hold the spacers rigidly, preventing any relaxation during the exposure phase, which ensures the deflection remains constant.^[26] Following the compression period, the device is removed from the controlled environment, and the specimen is disassembled and allowed to recover for 30 minutes at ambient room temperature and standard atmospheric conditions.^[4] The recovered thickness is then measured and compared to the original thickness and the spacer thickness to quantify the permanent deformation, with the compression set value calculated as outlined in the relevant formulas section.^[4] This method is particularly suitable for assessing materials intended for applications involving sustained strain, such as seals and gaskets, where maintaining shape under constant deformation is critical for long-term performance.^[27] It provides insights into the material's resilience in scenarios mimicking constrained installations, helping engineers select compounds that minimize permanent set in dynamic sealing environments.^[28]

Calculation Formulas

The compression set for elastomers is quantified using specific formulas derived from ASTM D395, which process measurements obtained from standardized test procedures.^[29] For Method A (constant force), the compression set C_A is calculated as:

C_A = \frac{t_0 - t_i}{t_0} \times 100\%

where t_0 is the original specimen thickness and t_i is the thickness after a specified recovery period. This formula represents the ratio of the permanent (unrecovered) deformation to the initial thickness, reflecting the material's elastic recovery under sustained compressive force without normalization for the exact deflection achieved.^[29] For Method B (constant deflection), the compression set C_B is given by:

C_B = \frac{t_0 - t_i}{t_0 - t_n} \times 100\%

where t_0 is the original specimen thickness, t_i is the thickness after recovery, and t_n is the thickness imposed by the spacer bar during deflection. This derivation normalizes the permanent deformation against the controlled deflection, isolating the extent of set independent of minor variations in actual compression depth.^[29] Both formulas yield results in percentage terms, with thicknesses measured to a precision of 0.01 mm using calipers or micrometers as specified in the standard; this resolution accounts for typical specimen dimensions around 6-13 mm.^[29] Error sources in these calculations can arise from uneven compression due to fixture misalignment or specimen adhesion to platens, potentially leading to variations of ±2-3 percentage points in interlaboratory reproducibility for materials like EPDM or NBR.^[30]

Variations in Testing Standards

The ISO 815 standard outlines methods for assessing the compression set characteristics of vulcanized and thermoplastic rubbers at ambient, elevated, or low temperatures, bearing similarity to ASTM D395 while employing metric units throughout.^[31] It specifies procedures such as Method A for constant strain testing using larger specimens to enhance accuracy for materials with low compression set, and includes a Method C variant that permits evaluation under oil or liquid immersion conditions to simulate real-world exposures.^[32] This immersion option measures permanent deformation after prolonged compression in fluids, providing insights into material performance in lubricated environments. Alternative standards address specialized material types and regional requirements. For instance, ASTM D1056 establishes specifications for flexible cellular materials like foams and sponge rubber, incorporating compression set evaluations at lower deflection levels—typically 25% or less—to avoid damaging the porous structure during testing.^[33] In Japan, the JIS K6262 standard governs compression set determination for vulcanized and thermoplastic rubbers, particularly those used in automotive applications, with procedures adapted for elevated temperatures relevant to engine components. Environmental adaptations extend these tests to fluid-immersed conditions, as seen in ASTM D1414, which evaluates compression set for O-rings and seals after exposure to oils or other liquids, thereby simulating operational stresses in hydraulic systems or oil seals. This method compresses specimens to 25% deflection while immersed, then measures recovery post-exposure to quantify degradation from chemical interactions. Revisions to ASTM D395, such as the 2014 and 2018 editions (reapproved 2025), expanded testing parameters to include higher temperatures up to 150°C, reflecting the demands of advanced elastomers like silicone for high-heat applications.^[1]

Influencing Factors

Material Composition

The compression set of a material is fundamentally influenced by its intrinsic composition, particularly the type of polymer backbone, the presence of fillers and additives, and the degree of cross-linking, which collectively dictate the polymer's ability to recover from deformation. These properties determine the elastic network's resilience, with variations arising from molecular structure and intermolecular interactions that resist permanent deformation under sustained load. Polymer type plays a pivotal role in compression set performance, as thermoplastics exhibit higher set values, often exceeding 50%, due to their linear or branched chains that lack permanent cross-links and thus undergo viscous flow and chain entanglement slippage during compression. In contrast, thermosets such as vulcanized rubber demonstrate significantly lower compression set, typically below 20%, owing to their covalently cross-linked networks that provide enhanced elastic recovery and prevent chain rearrangement. This difference stems from the irreversible chemical bonding in thermosets, which maintains structural integrity post-deformation, as established in foundational rubber elasticity theories. Fillers and additives further modulate compression set by altering the polymer matrix's reinforcement and flexibility. For instance, carbon black acts as a reinforcing filler that reduces compression set by strengthening polymer chains through physical adsorption and restricting molecular mobility, thereby improving load distribution and recovery. Conversely, plasticizers increase compression set by softening the material, enhancing chain slippage and reducing intermolecular forces, which leads to greater permanent deformation. These effects are quantified in elastomer formulations where optimal filler loading balances reinforcement without inducing brittleness. Cross-link density is a critical compositional parameter that directly correlates with compression set resistance, where higher densities enhance recovery by forming a denser elastic network. This is achieved through processes like sulfur curing, which introduces covalent bonds between polymer chains, increasing the material's modulus. The relationship can be expressed via the rubber elasticity equation G = \nu RT, where G is the shear modulus, \nu is the density of cross-linked moles per unit volume, R is the gas constant, and T is temperature; higher \nu values thus yield lower compression set by amplifying elastic restoring forces. Optimal cross-link densities, typically in the range of 10^{-4} to 10^{-3} mol/cm³ for rubbers, minimize set while preserving flexibility. Specific elastomers exemplify these compositional influences: nitrile rubber (NBR), with its acrylonitrile content providing polarity and oil resistance, achieves low compression set (around 10-25%) in lubricated environments due to its balanced cross-linking and minimal chain relaxation in non-polar media. Similarly, ethylene propylene diene monomer (EPDM) rubber, featuring a saturated backbone with ethylene-propylene copolymerization and diene cross-linking sites, exhibits excellent compression set below 15% in oxidative or UV-exposed conditions, attributed to its weather-resistant formulation and high cross-link efficiency via peroxide or sulfur systems.

Environmental Conditions

Environmental conditions during compression testing or service significantly influence the compression set of elastomers, as they alter molecular mobility, chain interactions, and degradation pathways. Temperature is a primary factor, with elevated levels accelerating viscoelastic relaxation and chemical degradation, thereby increasing permanent deformation. For instance, in silicone rubbers used for sealing, aging severity escalates above 80°C, leading to higher permanent compression set values due to decomposition of cross-linker units and methyl groups.^[34] Conversely, low temperatures near or below the glass transition temperature (Tg) reduce elastic recovery, causing compression set to rise dramatically; in hydrogenated nitrile butadiene rubber (HNBR), set reaches 70–100% at Tg (approximately −16°C), attributed to increased stiffness from restricted chain motion.^[35] Crystallization in certain rubbers, such as natural rubber below −25°C, further exacerbates this effect by promoting rigid structures that hinder recovery.^[36] The duration of compressive stress exposure directly impacts compression set through creep mechanisms inherent to viscoelastic materials. Prolonged compression allows for greater internal structural relaxation and chain slippage, resulting in higher set values; standard tests reveal that recovery after 30 minutes underestimates permanent deformation, while measurements after 24 hours better capture long-term effects.^[36] In EPDM elastomers, compression set increases with testing time at elevated temperatures, such as from 22 hours to 70 hours at 80°C, due to cumulative viscous flow.^[37] Viscoelastic models describe this time dependence logarithmically, reflecting the slowing rate of deformation over extended periods like 1000 hours in service simulations.^[8] Humidity and oxidative environments degrade elastomer performance by promoting hydrolysis and chain scission, particularly in unsaturated rubbers. Exposure to humid air accelerates water diffusion, which weakens crosslinks and elevates compression set; for natural rubber at 88% relative humidity, water absorption below 1% nonetheless boosts stress relaxation by 60%, indirectly worsening set through reduced elasticity.^[36] Oxidation in air, especially at elevated temperatures, causes surface hardening and internal chain breakage, linearly increasing compression set with aging time as oxygen diffuses into the matrix.^[38] Testing in inert atmospheres mitigates these effects by limiting oxidative reactions, yielding lower set values compared to air-exposed conditions.^[36] Chemical exposure, such as to oils, induces swelling that diminishes mechanical integrity and amplifies compression set. Immersion in crude oil or acids causes volume expansion in compatible elastomers like EPDM, reducing hardness and elasticity, with exposed samples exhibiting significantly higher set than unexposed ones—often by factors exceeding baseline values after prolonged contact.^[37] This swelling disrupts crosslink density, leading to poorer recovery; for oil-swelling elastomers at 60°C, post-exposure compression set rises notably due to enhanced fluid penetration and structural softening.^[37]

Processing Parameters

Processing parameters during manufacturing play a critical role in determining the compression set of elastomers, as they influence the cross-linking network, stress distribution, and overall structural integrity of the material. Curing conditions, in particular, must be optimized to avoid over-vulcanization, which can lead to reversion in natural rubber (NR), causing degradation of the polymer chains and an increase in compression set due to reduced elastic recovery.^[39] Optimal time-temperature profiles, such as curing NR at 150°C for approximately 10 minutes, promote uniform cross-linking without reversion, resulting in lower compression set values and enhanced long-term elasticity.^[40] Mixing and extrusion processes significantly affect filler dispersion, where poor uniformity creates weak points in the elastomer matrix, leading to localized stress concentrations that elevate compression set by up to 15% compared to well-dispersed systems.^[41] Achieving homogeneous filler distribution through controlled shear during mixing minimizes these defects, ensuring better load transfer and reduced permanent deformation under compression.^[42] Post-processing techniques like annealing help mitigate internal stresses developed during molding, thereby lowering compression set by allowing molecular relaxation and completion of cross-linking.^[43] For instance, in silicone rubbers, high-temperature post-curing acts as an annealing step that removes volatile by-products and optimizes the network structure, improving elastic recovery.^[43] Similarly, molding pressure influences material uniformity; inadequate pressure can result in voids or uneven flow, compromising the consistency of the cross-linked structure and increasing variability in compression set performance across parts.^[44]

Applications and Implications

Industrial Applications

Low-compression-set materials, particularly elastomers like nitrile, fluorocarbon, and EPDM, are essential in industrial sealing applications to maintain long-term integrity and prevent fluid or gas leakage under sustained pressure.^[45] These properties ensure reliable performance in demanding environments, where materials with compression sets typically under 20-30% are selected to minimize permanent deformation.^[45] In seals and gaskets, O-rings made from low-compression-set elastomers such as nitrile or fluorocarbon are widely used in hydraulic systems to achieve effective sealing with squeeze ratios of 15-30%, preventing leaks by resisting permanent deformation after extended compression.^[45] For instance, in oil and gas applications, these O-rings have been employed since the 1940s in high-pressure hydraulic and fuel systems, leveraging their low set (often 10-20% under standard test conditions) to handle aggressive media and temperatures up to 135°C.^[46]^[45] Automotive components like engine mounts and weatherstrips commonly utilize EPDM rubber due to its low compression set, typically 20-30%, which supports vibration damping and sealing durability exceeding 10 years under environmental exposure.^[47]^[47] This material's resilience to ozone, UV, and weathering ensures consistent performance in dynamic seals exposed to automotive operating conditions.^[48] In aerospace, fluorosilicone seals are favored for fuel systems, offering excellent compression set resistance alongside a broad temperature range from -60°C to 204°C, enabling minimal deformation in static sealing applications involving fuels and oils.^[49]^[50] Medical devices, including silicone-based prosthetics, rely on materials with low compression sets, typically 10-30%, to provide biocompatibility and long-term durability, ensuring hypoallergenic contact with tissues without adverse reactions or loss of shape under compressive forces.^[51]^[52]

Performance Evaluation

In quality control and design processes for elastomeric components, original equipment manufacturers (OEMs) establish specific thresholds for compression set to ensure long-term functionality, often specifying limits such as less than 25% permanent deformation after 22 hours of compression at elevated temperatures like 100°C or 125°C for materials like EPDM used in seals.^[53] These specifications are derived from standards like ASTM D2000, which guide material selection for applications requiring sustained sealing integrity. Exceeding these thresholds can result in failure modes such as extrusion under load, where the elastomer fails to recover its shape, leading to gaps that allow fluid leakage or material displacement in high-pressure environments.^[54] High compression set values correlate strongly with reduced service life in elastomers, as they indicate diminished elastic recovery and accelerated degradation under operational stresses, potentially halving the expected lifespan in critical applications like gaskets and O-rings.^[55] To predict these effects, the Arrhenius model is commonly applied, extrapolating accelerated aging test data—such as compression set measurements at elevated temperatures—to estimate real-world longevity under normal conditions, enabling designers to forecast performance over years of use.^[56] For comparative analysis, compression set is evaluated alongside metrics like tensile set, which measures permanent deformation after stretching, and creep, which quantifies gradual deformation under constant stress; compression set is particularly indicative of performance under static compressive loads, making it a preferred benchmark for seals in non-dynamic scenarios where recovery from deflection is essential.^[2] High compression set in heat-exposed rubber components can contribute to seal degradation in automotive systems, underscoring the metric's role in preventing failures.^[57]

Strategies for Improvement

To minimize compression set, material selection plays a pivotal role, particularly in demanding applications. High-resilience elastomers such as hydrogenated nitrile butadiene rubber (HNBR) are recommended over natural rubber (NR) for harsh environments involving elevated temperatures and oxidative exposure, as HNBR exhibits significantly lower compression set due to its enhanced thermal stability and resistance to degradation, with peroxide-cured variants showing improved recovery at temperatures up to 150°C.^[58]^[59] In contrast, NR, while offering excellent resilience under ambient conditions, experiences rapid set increase in such environments owing to its susceptibility to thermal and oxidative breakdown.^[60] Design optimizations further mitigate compression set by distributing stress more evenly. Incorporating strain-relief geometries, such as chamfered edges or grooved profiles in seals, reduces localized compression exceeding 25%, preventing excessive deformation and promoting better elastic recovery without altering material properties.^[61] Additives and treatments target underlying degradation mechanisms to enhance performance. Antioxidants, such as phenolic or amine-based compounds, inhibit oxidation-induced chain scission and cross-linking, thereby preventing permanent set in elastomers exposed to air and heat; for instance, they extend service life by delaying thermo-oxidative effects during prolonged compression.^[62] In thermoplastic elastomers (TPEs), dynamic vulcanization—cross-linking the rubber phase in situ during blending—improves network integrity, reducing compression set by up to 30% compared to non-vulcanized blends, as evidenced by finer rubber particle dispersion and higher elasticity retention at elevated temperatures.^[63]^[64] Recent innovations leverage nanomaterials to achieve low compression set in specialized compounds. In the 2020s, incorporating graphene nanoplatelets into fluoroelastomers like Viton has improved mechanical and thermal properties, supporting reliable sealing in electric vehicle (EV) battery systems where thermal management demands exceptional resilience.^[65] As of 2025, research into bio-based elastomers and AI-optimized formulations shows promise for further reducing compression set in sustainable applications for renewable energy seals.^[59]

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They also provide better compression set properties for gaskets that need long-term sealing at elevated temperatures. In addition, peroxide cured silicones ...
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[PDF] Ways to Manipulate and Improve Peroxide-cured Rubber
The higher bond strength means the heat needed to break them is greater and thus the resistance to heat and compression set is better in elastomers with ...
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[PDF] Parker O-Ring Handbook ORD 5700
This book contains extensive information about the properties of basic sealing elastomers, as well as examples of typical o-ring applications, fundamentals of ...
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History of O rings - Specialist Sealing Products
Mar 26, 2025 · By 1940, the o-ring fast became the seal of choice, helping to initially seal the gap in hydraulic landing gases and then go on to support much ...
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Rubber EPDM Gaskets: Properties, Applications, Manufacturing ...
Jan 2, 2025 · EPDM's low compression set (<15%) allows it to maintain its sealing integrity even after repeated stress, making it a preferred material for ...
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How EPDM Rubber Improves Industrial Sealing Durability - Alanto
Mar 11, 2025 · EPDM rubber stands out for its weather resistance, flexibility, and long lifespan. It provides airtight and watertight sealing, ensuring protection against ...Why Epdm Rubber Is Essential... · Epdm Rubber In Construction... · Epdm Rubber In Automotive...
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Getting To Know O-Ring Materials: Fluorosilicone - APG
Fluorosilicone has excellent compression set, is stable in extreme temperatures, and resistant to fuel, oils, sunlight, ozone, and weathering, but is not for ...
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Fluorosilicone Rubber Products - FVMQ Silicone Elastomers
Auto fuel emission control systems. Primarily for static sealing applications. Temperature Range: Standard Compound: -75⁰ to +400⁰F. (Dry Heat Only). Hardness ( ...
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Silicone‐based biomaterials for biomedical applications
May 26, 2021 · Silicone is highly biocompatible and bio-durable when interacting with host tissues. The hydrophobicity and low surface tension of silicone ...
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What is EPDM Rubber?
First and foremost, it is extremely durable. Considered to be the premier weather-resistant synthetic elastomer, EPDM rubber has excellent heat, ozone, UV, ...Missing: engine mounts
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Static Seal Failure Modes - Stockwell Elastomerics
May 22, 2020 · Seals typically fail for one of 5 common reasons: chemical swell, compression set, extrusion/nibbling, installation damage, and thermal
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Compression Set in Elastomers: How It Happens and How to Prevent It
Aug 11, 2025 · Compression set is the permanent deformation of an elastomer after it has been compressed and released. In sealing applications, elastomers are ...<|control11|><|separator|>
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[PDF] Arrhenius seal life prediction project: results and analysis
Series of models used to fit and extrapolate at long-term prediction for compression set and compression stress relaxation. Properties. Compression Set.
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[PDF] Toyota Safety Recall 10V-499 - nhtsa
Dec 2, 2010 · The repair will require the usage of Toyota Rubber Grease (1 gram/vehicle) and a Rubber Seal Kit. (Brake Master Cylinder Cup Kit). These ...
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HNBR Rubber, Hydrogenated Nitrile Rubber - Savvy
Mar 18, 2022 · Due to high heat resistance, peroxide-cured HNBR compounds have better compression set at high temperatures. Hydrogenated nitrile rubber is ...Missing: NR | Show results with:NR
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Long-term ISO 23936-2 sweet oil ageing of HNBR - ScienceDirect.com
Considering times longer than 100 s, the increase in compression set in HNBR aged at 130 °C is not greater than 7%, while ageing at 150 °C results in slower ...
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The group of general-purpose rubbers
Jan 4, 2023 · It has very good elasticity, high tear resistance, excellent elongation and tensile strength, and low compression set. NR is resistant to water ...
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How to optimize compression set and resilience of rubber materials
Sep 14, 2024 · Over-vulcanization: Over-vulcanization will make the rubber stiff and brittle, reduce the resilience, and although the compression set may be ...
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Effectiveness of different kinds of antioxidants in resin‐cured ...
Jul 18, 2017 · The antioxidants can delay the thermo-oxidative degradation of rubber molecules happening at high temperatures in oxygen environment by ...
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Method for improving compression set in thermoplastic vulcanizates
Composition and methods of formulating thermoplastic vulcanizates to achieve an improved high temperature (between 70° C. 100° C.) compression set<|separator|>
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US7485682B2 - Thermoplastic elastomer composition
U.S. Pat. No. 4,927,882 claims a thermoplastic elastomer composition having a compression set less than about 30% and produced by dynamic vulcanization of SBR ...<|separator|>
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Understanding the Effect of Graphene Nanoplatelet Size on ... - MDPI
Moreover, high compression set values suggest stronger affinity between the matrix and the fillers, leading to reduced elasticity of the fluoroelastomer. This ...
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Graphene nanotubes offer an advanced set of properties to meet EV ...
Sep 29, 2022 · Graphene nanotubes has developed an advanced engineering solution for battery packs. They utilize reinforced glass fiber filled polyphenylene sulfide (PPS).