Lexicon of Elastomer Technology

(A-Z)

Lexicon of Elastomer Technology

Bonding of elastomers to substrates like glass, metal, or plastic. Important for co-extrusion and overmoulding. Adhesion promoters or plasma treatment improve bonding.

Tests simulating long-term stress (hot air, ozone, UV, media immersion). Used to predict seal lifetime.

Additives that protect elastomers from UV, ozone, and thermal degradation. Especially important for EPDM, CR, and Silicone in outdoor use.

Mixture of different polymers. Common blends: PVC/NBR, TPE/PP – to combine elasticity, temperature resistance, and processability.

Used to ensure adhesion between NBR, FKM, EPDM and metal or plastic in multi-material parts.

Evaluation of material behaviour after exposure to various media (oils, fuels, water/steam, acids/alkalis, cleaning/disinfection agents).

Key standards

  • ISO 1817:2024 – Effect of liquids on vulcanized or thermoplastic rubber (changes in mass/volume/hardness/strength after immersion in specified liquids).

  • ASTM D471 – US equivalent (often correlated with ISO 1817; specification alignment required). 

  • Note: chemical resistance must always be reported as temperature- and time-dependent (e.g. 70 h/23 °C, 168 h/100 °C) with swelling and pre-strain documented.

Typical material behaviour (indicative)

  • EPDM: excellent in hot water/steam and alkalis; poor in mineral oils/fuels.

  • NBR/HNBR: excellent in oils/fuels; HNBR more heat-resistant.

  • FKM/FFKM: very high chemical resistance incl. fuels/aromatics.

  • Silicone: good against water/alcohols/cleaners; sensitive to mineral oils/hydrocarbons.

  • TPE: strongly type-dependent (TPE-S, -V, -E, -U, etc.); always check media and temperature.

Extended tests

  • Abrasion: ISO 4649:2024 (rotating drum volume loss, methods A/B).

  • Gas/vapour permeability: ISO 2782-1:2022 (differential pressure methods), ISO 2782-2:2018 (gas transmission).

  • Ozone cracking resistance: ISO 1431-1:2022 (visual/image analysis, standard climate, defined ozone concentration).

A mix of base rubber, fillers, curing agents, and additives. Each material (NBR, HNBR, FKM, etc.) has tai-lored compounds for specific uses.

Used to produce foam rubber, EPDM, FKM, Silicone, or TPE components, especially seals and gaskets.eee/c

Measurement of permanent deformation after compression. Critical for long-lasting sealing materials like foam rubber, FKM, and Silicone.

What is CR?

CR (Chloroprene Rubber), commonly known under the trade name Neoprene®, is a versatile synthetic rubber offering good weather, ozone and oil resistance combined with excellent mechanical properties.

Properties

  • Temperature range approximately -35 °C to +100 °C
  • Good weather and ozone resistance
  • Good oil resistance
  • High mechanical strength
  • Good flame resistance

Typical applications

  • Industrial seals
  • Cable jackets
  • Conveyor belts
  • Vibration dampers
  • Marine applications

Limitations

Not suitable for aromatic solvents or strong oxidising agents.

What is CR Sponge Rubber?

CR Sponge Rubber, also known as Neoprene Sponge, is an elastomeric foam based on chloroprene rubber (CR). It offers an excellent balance of mechanical strength together with good resistance to weathering, ozone, ageing and many oils.

Depending on the application, CR sponge rubber is available in open-cell or closed-cell structures. For technical sealing applications, closed-cell grades are predominantly used because they provide low water absorption and excellent sealing performance.

Thanks to its versatility, CR sponge rubber is widely used in industrial applications where durability, reliability and good mechanical properties are required.

Properties

  • Temperature resistance from approximately -35 °C to +100 °C
  • Available in open-cell or closed-cell structures
  • Good resistance to weathering, ozone and UV radiation
  • Good resistance to oils, greases and many chemicals
  • Good mechanical strength
  • Good abrasion resistance
  • Good cushioning and insulation properties
  • Good flame resistance
  • Long service life in demanding environments

Typical applications

CR sponge rubber is commonly used for:

  • Industrial seals
  • Enclosure seals
  • Automotive seals
  • Marine and offshore applications
  • Mechanical engineering
  • Vibration dampers
  • Sound insulation
  • Cable protection
  • Technical moulded parts

Typical industries include:

  • Mechanical engineering
  • Automotive industry
  • Marine industry
  • Electrical industry
  • Construction industry
  • Industrial equipment

Limitations

CR sponge rubber has limited resistance to aromatic and chlorinated solvents as well as strong oxidising agents. For continuous exposure to fuels or highly aggressive chemicals, materials such as NBR, FKM or FFKM are often more suitable.

Chemical (for EPDM, FKM, NBR) or physical (for TPE). Determines final mechanical properties.

Chemical process (e.g., vulcanization) that gives rubber its elastic properties. TPE achieves elasticity through physical properties and does not require curing.

Typical values:
PTFE: very high (~2.2g/cm³)
Foam rubber: very low (due to cellular structure)
TPE, NBR, EPDM: around 1.1–1.3g/cm³

Elastomers such as CR, HNBR, and TPE perform well under vibration and impact—used in mounts or shock-absorbing components.

What is EPDM?

EPDM (Ethylene Propylene Diene Rubber) is a versatile synthetic rubber offering excellent resistance to weathering, ozone, UV radiation, water and steam. Due to its outstanding ageing resistance, EPDM is widely used for both indoor and outdoor sealing applications.

Properties

  • Temperature resistance from approximately -40 °C to +120 °C
  • Excellent weather, ozone and UV resistance
  • Very good resistance to water, steam and many chemicals
  • Good electrical insulation properties
  • Excellent ageing resistance

Typical applications

  • O-rings
  • Flat gaskets
  • Window and door seals
  • Drinking water applications
  • Heating and sanitary systems
  • Roofing and façade systems

Limitations

Not suitable for mineral oils, fuels or most lubricants.

What is EPDM Sponge Rubber?

EPDM Sponge Rubber is an elastomeric foam based on Ethylene Propylene Diene Rubber (EPDM). It is renowned for its outstanding resistance to weathering, ozone, UV radiation and water, making it an ideal material for both indoor and outdoor sealing applications.

Depending on the application, EPDM sponge rubber is available in open-cell or closed-cell structures. For technical sealing applications, closed-cell grades are predominantly used because they effectively repel moisture and provide excellent long-term sealing performance.

Thanks to its excellent ageing resistance, flexibility and long service life, EPDM sponge rubber is one of the most widely used sponge elastomers in construction, industrial and automotive applications.

Properties

  • Temperature resistance from approximately -40 °C to +120 °C
  • Available in open-cell or closed-cell structures
  • Outstanding weather, ozone and UV resistance
  • Excellent resistance to water and moisture
  • Excellent ageing resistance
  • Good elasticity and recovery properties
  • Good thermal and acoustic insulation
  • Excellent vibration and shock absorption
  • Long service life, even in outdoor environments

Typical applications

EPDM sponge rubber is commonly used for:

  • Window and door seals
  • Façade and building seals
  • Roofing systems
  • Automotive seals
  • Enclosure seals
  • HVAC systems
  • Sound insulation
  • Mechanical engineering applications

Typical industries include:

  • Construction industry
  • Automotive industry
  • Mechanical engineering
  • HVAC industry
  • Electrical industry
  • Industrial equipment

Limitations

EPDM sponge rubber is not suitable for contact with mineral oils, fuels, greases or many hydrocarbons. For applications requiring oil or fuel resistance, materials such as NBR or HNBR are generally more suitable.

What is FFKM?

FFKM (Perfluoroelastomer) is the highest-performance elastomer available for the most demanding sealing applications. It combines the near-universal chemical resistance of PTFE with the elasticity of rubber, making it the preferred choice when even FKM reaches its limits.

Due to its exceptional performance, FFKM is one of the most expensive elastomer materials and is mainly used in highly critical applications.

Properties of FFKM

  • Outstanding chemical resistance to almost all chemicals
  • Excellent high-temperature resistance (depending on the compound up to approximately +325 °C)
  • Exceptional resistance to ageing, ozone and weathering
  • Very low compression set
  • High purity for sensitive applications
  • Long service life under extreme operating conditions

Typical applications

FFKM is used wherever maximum sealing performance is required:

  • Chemical processing plants
  • Semiconductor industry
  • Pharmaceutical and biotechnology industries
  • Food and beverage industry
  • Oil and gas industry
  • Vacuum systems
  • High-temperature applications

Typical products include:

  • O-rings
  • Flat gaskets
  • Custom moulded parts
  • Valve seals

Limitations

The main disadvantage of FFKM is its high cost. Therefore, it is typically selected only when other elastomer materials such as FKM, EPDM or HNBR cannot meet the required chemical or thermal resistance. Under certain conditions, FFKM may also have limitations when exposed to elemental fluorine or specific fluorinated media.

Examples: carbon black increases strength (common in NBR, CR); chalk reduces cost (e.g., in basic PVC compounds).

The fire performance of elastomers is assessed using international standards covering flammability, smoke density and toxicity.

  • Key standards:

    • EN 45545 (railway, Europe): assesses materials in rolling stock against fire safety requirements (Hazard Levels HL1–HL3). Tests: flammability, smoke density, smoke toxicity.

    • DIN 4102 (Germany): building material classes B1 (hardly flammable), B2 (normally flammable), B3 (easily flammable).

    • EN 13501-1 (Europe, construction): classification A1–F with smoke (s1–s3) and burning droplets (d0–d2).

    • UL 94 (USA, plastics): horizontal/vertical flame classifications (HB, V-2, V-1, V-0, 5VA/5VB).

    • FMVSS 302 (automotive, USA): horizontal burning rate of materials.

  • Material behaviour:

    • Silicone: inherently flame-retardant, often UL 94 V-0, typically compliant with EN 45545 HL1–HL3.

    • TPE: variable flammability; halogen-free flame retardants required to achieve EN 13501-1 (e.g. B-s2,d0) or EN 45545 classification.

    • EPDM: with flame retardants, widely used in building and railway applications.

    • FKM / FFKM: excellent self-extinguishing properties, high cost.

  • Relevance:

    • Construction: EN 13501-1 applies for façades, doors, windows.

    • Railway: EN 45545 mandatory (e.g. R22/R23 for seals).

    • Automotive: FMVSS 302 standard.

What is FKM?

FKM (Fluoroelastomer) is a high-performance synthetic rubber known for its excellent resistance to high temperatures, oils, fuels and a wide range of chemicals. The designation FKM is defined in ISO 1629. One of the best-known trade names is Viton®.

Thanks to its outstanding resistance to aggressive media, FKM is widely used in demanding sealing applications where standard elastomers such as NBR or EPDM are no longer suitable.

Properties of FKM

  • Excellent temperature resistance (approximately -20 °C to +200 °C, depending on the compound even higher)
  • Outstanding resistance to mineral oils, lubricants and fuels
  • Very good resistance to many acids and chemicals
  • Excellent resistance to ozone, weathering and ageing
  • Low gas permeability
  • Good compression set properties

Typical applications

FKM is commonly used for:

  • O-rings
  • Radial shaft seals
  • Flat gaskets
  • Moulded rubber parts
  • Valve seals
  • Hydraulic and pneumatic seals

Typical industries include:

  • Automotive industry
  • Chemical industry
  • Mechanical engineering
  • Aerospace
  • Oil and gas industry
  • Process industry

Limitations

FKM is generally not recommended for:

  • Hot water
  • Steam
  • Glycol-based brake fluids
  • Polar solvents such as acetone
  • Certain amines and organic acids

For these applications, materials such as EPDM or FFKM are often more suitable.

Resistance to repeated bending and flexing. Silicone, EPDM, and TPE perform well in this area—important for dynamic seals and flexible connectors.

Typical ranges:
TPE: 30–90 Shore A
Foam rubber: very soft (~10–30 Shore 00)
PTFE: hard (Shore D)
FKM, HNBR, CR: medium to high hardness (60–90 Shore A)

What is HNBR?

HNBR (Hydrogenated Nitrile Butadiene Rubber) is an enhanced version of NBR. Hydrogenation significantly improves heat, ozone and ageing resistance while maintaining excellent oil resistance.

Properties

  • Temperature range approximately -30 °C to +150 °C
  • Excellent oil and fuel resistance
  • High mechanical strength
  • Outstanding ozone and ageing resistance
  • Good abrasion resistance

Typical applications

  • Automotive industry
  • Air conditioning systems
  • Oil and gas industry
  • Hydraulic systems
  • Mechanical engineering

Limitations

More expensive than NBR and not suitable for highly polar media.

Efficient method for complex parts made from TPE, FKM, Silicone, CR, etc. Fast, repeatable, automated.

Ideal for TPE, Silicone, PVC, FKM parts. Ensures high precision and fast cycle times.

Main component of natural rubber (NR). Also found in synthetic IR rubber, less common in technical seal-ing.

Measures impact resilience – less common for rubber, more relevant for TPE or PVC under sudden loads.

German term for elastomers. Covers materials like NBR, EPDM, Silicone, CR, FKM, HNBR, etc.

What is LSR?

LSR (Liquid Silicone Rubber) is a high-performance liquid silicone elastomer processed by injection moulding. The material consists of two liquid components that are mixed and cured under heat during the moulding process. This manufacturing method enables the production of highly precise moulded parts with consistent quality and tight dimensional tolerances.

LSR offers outstanding resistance to high and low temperatures, excellent flexibility and exceptional resistance to weathering, ozone and UV radiation. Thanks to its high purity and physiological safety, LSR is widely used in demanding applications within the medical, food, automotive and electrical industries.

Properties

  • Temperature resistance from approximately -60 °C to +200 °C
  • Excellent weather, ozone and UV resistance
  • Outstanding ageing resistance
  • High elasticity and flexibility
  • Excellent electrical insulation properties
  • High precision and dimensional stability
  • Odourless and tasteless
  • Suitable for food-contact and medical applications (depending on grade and approval)
  • Ideal for automated high-volume production

Typical applications

LSR is commonly used for:

  • Precision seals
  • O-rings
  • Membranes
  • Valves
  • Medical moulded parts
  • Baby care and food-contact products
  • Connectors and insulating components
  • Sensor and electronic components
  • Automotive moulded parts

Typical industries include:

  • Medical technology
  • Food industry
  • Automotive industry
  • Electrical and electronics industry
  • Mechanical engineering
  • Consumer goods industry

Limitations

LSR has limited resistance to mineral oils, fuels, concentrated acids and certain organic solvents. For applications involving continuous exposure to oils or aggressive chemicals, materials such as FKM or FFKM are often more suitable. In addition, LSR is intended exclusively for injection-moulded parts and cannot be extruded into sealing profiles.

Rubber compounds (EPDM, NBR) are processed in internal mixers. TPE and PVC are processed thermo-plastically (extrusion, injection).

What is NBR?

NBR (Nitrile Butadiene Rubber) is one of the most commonly used elastomers for seals exposed to oils, greases and fuels. It combines good abrasion resistance with cost-effective performance.

Properties

  • Temperature range approximately -30 °C to +100 °C
  • Excellent resistance to oils and fuels
  • Good abrasion resistance
  • Good mechanical properties
  • Cost-effective material

Typical applications

  • O-rings
  • Shaft seals
  • Hydraulic seals
  • Pneumatic seals
  • Fuel systems

Limitations

Not suitable for ozone, UV exposure, weathering or hot water.

What is NBR Sponge Rubber?

NBR Sponge Rubber is an elastomeric foam based on Nitrile Butadiene Rubber (NBR). It is well known for its excellent resistance to mineral oils, fuels, lubricants and greases, making it the preferred choice for sealing applications requiring oil resistance.

Depending on the application, NBR sponge rubber is available in open-cell or closed-cell structures. For technical sealing applications, closed-cell grades are predominantly used because they provide low liquid absorption and excellent sealing performance.

Thanks to its good mechanical properties, high abrasion resistance and excellent oil resistance, NBR sponge rubber is widely used in demanding industrial applications.

Properties

  • Temperature resistance from approximately -30 °C to +100 °C
  • Available in open-cell or closed-cell structures
  • Excellent resistance to mineral oils, fuels and lubricants
  • Good mechanical strength
  • Good abrasion and wear resistance
  • Good elasticity and recovery properties
  • Good cushioning and insulation properties
  • Low liquid absorption in closed-cell grades
  • Cost-effective material for many industrial applications

Typical applications

NBR sponge rubber is commonly used for:

  • Oil- and fuel-resistant seals
  • Enclosure seals
  • Automotive seals
  • Fuel systems
  • Hydraulic and pneumatic systems
  • Mechanical engineering
  • Vibration damping
  • Technical moulded parts
  • Industrial equipment

Typical industries include:

  • Automotive industry
  • Mechanical engineering
  • Hydraulics and pneumatics
  • Oil and gas industry
  • Industrial equipment
  • Industrial automation

Limitations

NBR sponge rubber has limited resistance to ozone, UV radiation, weathering, hot water and steam. For outdoor applications or long-term exposure to weather, materials such as EPDM or CR are generally more suitable.

What is NR?

NR (Natural Rubber) is obtained from the latex of the Hevea brasiliensis rubber tree. It is renowned for its outstanding elasticity, high tear strength and excellent dynamic performance.

Properties

  • Temperature range approximately -50 °C to +80 °C
  • Excellent elasticity
  • Outstanding tear and abrasion resistance
  • Excellent dynamic properties
  • High mechanical strength

Typical applications

  • Anti-vibration components
  • Rubber-to-metal bonded parts
  • Conveyor systems
  • Tyres
  • Technical moulded parts

Limitations

Not suitable for oils, fuels, ozone or UV exposure.

Unwanted excessive vulcanization. A concern with EPDM, NBR – not applicable to TPE, which does not cure chemically.

TPE is ideal for 2K molding (e.g., soft-touch).
Can be combined with metal, PP, PA, etc.

High: EPDM, FKM, Silicone, CR
Low: NBR, foam rubber (unless stabilized)

Alternative to sulfur curing – used for FKM, EPDM, Silicone. Enhances heat resistance and lowers emis-sions.

Used for foam rubber, EPDM, FKM, Silicone parts.
TPE is generally injection molded.

What is PTFE?

PTFE (Polytetrafluoroethylene) is a high-performance engineering plastic renowned for its exceptional chemical resistance and extremely wide operating temperature range. It is widely known under the trade name Teflon® and is characterised by its very low coefficient of friction and excellent non-stick properties.

Unlike elastomers, PTFE is not elastic. It is therefore widely used for seals, sliding components and parts exposed to demanding chemical, thermal or mechanical conditions.

Properties

  • Temperature resistance from approximately -200 °C to +260 °C
  • Excellent resistance to almost all chemicals
  • Very low coefficient of friction
  • Outstanding non-stick properties
  • Excellent weather, ozone and UV resistance
  • Very low water absorption
  • Good electrical insulation properties

Typical applications

PTFE is commonly used for:

  • Flat gaskets
  • Guide rings and sliding elements
  • Valve seats
  • Bushings
  • Linings
  • Seals for aggressive chemicals
  • Food and pharmaceutical applications

Typical industries include:

  • Chemical industry
  • Mechanical engineering
  • Food industry
  • Pharmaceutical industry
  • Semiconductor industry
  • Oil and gas industry

Limitations

PTFE has limited elasticity and is therefore less suitable for dynamic sealing applications involving large deformations. Under continuous mechanical load, the material may also exhibit creep (cold flow).

From compound mixing to final product – varies by application (e.g., aerospace-grade FKM vs. basic foam rubber).

Uncured base elastomer. TPEs are already processable thermoplastics—no raw rubber phase.

Excellent in Silicone, TPE, natural rubber
Low in PTFE, which behaves more plastically.

Generic term for elastic polymers. Includes NBR, EPDM, FKM, Silicone, CR, HNBR, etc.

EPDM, FKM, and PTFE are highly stable. Natural rubber and soft TPE can degrade over time.

Examples:
TPE: wide range
PTFE: ~60 Shore D
FKM: 70–90 Shore A
Foam rubber: very soft (Shore 00)

High-performance elastomer with outstanding resistance to temperature and ageing.

  • Types:

    • HTV (solid rubber, High Temperature Vulcanizing) → suitable for extrusion (profiles, hoses) and injection moulding (moulded parts).

    • LSR (Liquid Silicone Rubber) → liquid, for precision injection-moulded parts, also in 2K technology.

    • RTV (Room Temperature Vulcanizing) → one- or two-component, curing at room temperature, e.g. for sealing and bonding.

  • Properties:

    • Temperature range: −50 to +250 °C (up to +300 °C for special grades).

    • Excellent resistance to weather, ozone and UV.

    • Remains flexible even at very low temperatures (down to −60 °C).

    • Electrically insulating or semi-conductive.

    • Odourless and tasteless, suitable for drinking water and food applications.

  • Mechanical data:

    • Density: 1.05–1.35 g/cm³

    • Hardness: 5–90 Shore A

    • Tensile strength: 5–11 N/mm²

    • Elongation at break: 100–900 %

    • Tear resistance: 5–50 N/mm

    • Compression set (175 °C, 22h): 20–25 %

  • Processing:

    • Extrusion: continuous profiles for doors, windows, façades, hoses.

    • Injection moulding: HTV or LSR parts, e.g. seals, grommets, membranes.

    • RTV: sealing and bonding applied directly during installation.

  • Typical applications:

    • Door and window seals, façade profiles.

    • Sanitary seals and moulded parts.

    • Automotive and mobile applications.

Best materials: FKM, FFKM, PTFE
Poor resistance: EPDM, TPE, foam rubber (open cell types)

Current core standards for elastomers (selection; “EN ISO” = EU adoption of ISO texts).

Mechanical

  • Tensile: ISO 37:2024 (tensile strength, elongation, stress-strain behaviour).

  • Tear strength: ISO 34-1:2022 (trouser/angle/crescent test pieces).

  • Rebound resilience: ISO 4662:2017 (pendulum/tripsometer).

  • Hardness: ISO 48-2:2018 (IRHD hardness), Shore hardness: defined in ISO 48-4 (replaces ISO 7619-1).

  • Density: ISO 2781:2018 (2 methods; quality control/mass calculation).

  • Compression set: ISO 815-1:2019 (ambient/elevated temperatures, methods A–C).

Fire behaviour (construction/rail/automotive)

  • EN 13501-1 (construction products: Euroclasses A1–F, smoke s1–s3, droplets d0–d2).

  • DIN 4102 (national legacy system: B1/B2/B3; now largely replaced by EN 13501-1).

  • EN 45545-2 (railway: material requirements by HL1–HL3 and R categories, e.g. R22/R23 for seals and hoses).

  • UL 94, FMVSS 302 (plastics/automotive; additional, informative).

NBR swells in fuels, EPDM in oils.
PTFE, FKM, FFKM resist most aggressive media.

Top performers:
FFKM: up to 300°C
PTFE: up to 260°C
Silicone: up to 230°C
TPE, NBR: ~100–120°C max

Elastomers expand more than glass or metal. Profiles must compensate movement.

Material family combining rubber-like properties with thermoplastic processability.

  • Properties:

    • Elastic without chemical crosslinking, reprocessable

    • Hardness: 30–90 Shore A

    • Heat resistance up to 100–120 °C

    • Good recovery behaviour, recyclable

  • Processing: extrusion, 2K injection moulding, overmoulding with rigid plastics

  • Typical applications: door and window seals, frame gaskets, façade profiles, seals in mobile applications

What is TPE Sponge Rubber?

TPE Sponge Rubber is an elastomeric foam based on thermoplastic elastomers (TPE). It combines the flexibility of rubber with the processing advantages of thermoplastics, making it an excellent choice for sealing, cushioning and insulation applications.

Depending on the application, TPE sponge rubber is available in open-cell or closed-cell structures. For technical sealing applications, closed-cell grades are predominantly used because they provide low water absorption and excellent sealing performance.

Thanks to its low weight, flexibility and cost-efficient processing by extrusion or injection moulding, TPE sponge rubber is widely used in industrial applications.

Properties

  • Temperature resistance from approximately -40 °C to +100 °C
  • Available in open-cell or closed-cell structures
  • Lightweight
  • Good elasticity and recovery properties
  • Good resistance to weathering, ozone and UV radiation
  • Good resistance to water and moisture
  • Good thermal and acoustic insulation
  • Excellent vibration and shock absorption
  • Recyclable and easy to process

Typical applications

TPE sponge rubber is commonly used for:

  • Sealing profiles
  • Window and door seals
  • Enclosure seals
  • Automotive seals
  • Cable grommets
  • Protective profiles
  • Sound insulation
  • Vibration damping
  • Technical moulded parts

Typical industries include:

  • Automotive industry
  • Mechanical engineering
  • Construction industry
  • Electrical industry
  • Household appliances
  • Industrial equipment

Limitations

TPE sponge rubber has limited resistance to mineral oils, fuels and certain organic solvents. For applications involving aggressive chemicals or high operating temperatures, materials such as FKM, FFKM or PTFE are often more suitable.

What is TPV?

TPV (Thermoplastic Vulcanizates) belong to the family of thermoplastic elastomers (TPEs), combining the elasticity of vulcanised rubber with the processing advantages of thermoplastics. TPV typically consists of finely cross-linked EPDM rubber dispersed within a polypropylene (PP) matrix.

TPV offers excellent resistance to weathering, ozone and ageing while allowing efficient processing by injection moulding or extrusion. This makes it an ideal material for applications requiring flexibility, durability and cost-effective manufacturing.

Properties

  • Temperature resistance from approximately -40 °C to +135 °C
  • Excellent weather, ozone and UV resistance
  • Good resistance to water and many chemicals
  • Good elasticity and recovery properties
  • Lightweight
  • Recyclable and easy to process
  • Suitable for injection moulding and extrusion

Typical applications

TPV is commonly used for:

  • Sealing profiles
  • Window and door seals
  • Automotive seals
  • Cable grommets
  • Bellows
  • Protective caps
  • Technical moulded parts

Typical industries include:

  • Automotive industry
  • Construction industry
  • Mechanical engineering
  • Electrical industry
  • Household appliances

Limitations

TPV has limited resistance to mineral oils, fuels and certain organic solvents. For applications involving aggressive chemicals or very high temperatures, materials such as FKM or PTFE are often a better choice.

High: EPDM, FKM, Silicone, PTFE
Low: NBR, PVC, TPE-S → needs stabilizers

What is VMQ Sponge Rubber?

VMQ Sponge Rubber, also known as Silicone Sponge, is an elastomeric foam based on silicone rubber (VMQ). It is characterised by its exceptionally wide operating temperature range and outstanding resistance to weathering, ozone, UV radiation and ageing. Silicone sponge also offers excellent flexibility, making it suitable for demanding applications in the food, medical, electrical and electronics industries.

Depending on the application, VMQ sponge rubber is available in open-cell or closed-cell structures. For technical sealing applications, closed-cell grades are predominantly used because they provide low water absorption and excellent sealing performance.

Thanks to its excellent temperature resistance, long service life and physiological safety (depending on the grade), VMQ sponge rubber is one of the most versatile elastomer foams for demanding applications.

Properties

  • Temperature resistance from approximately -60 °C to +200 °C
  • Available in open-cell or closed-cell structures
  • Outstanding weather, ozone and UV resistance
  • Excellent ageing resistance
  • High elasticity and flexibility
  • Good electrical insulation properties
  • Good thermal and acoustic insulation
  • Excellent vibration and shock absorption
  • Suitable for food-contact and medical applications (depending on grade and approval)

Typical applications

VMQ sponge rubber is commonly used for:

  • High-temperature seals
  • Enclosure seals
  • Food and beverage equipment
  • Medical technology
  • Electrical and electronics industry
  • Lighting systems
  • Control cabinets and enclosures
  • Thermal and acoustic insulation
  • Technical moulded parts

Typical industries include:

  • Food industry
  • Medical technology
  • Electrical industry
  • Electronics industry
  • Mechanical engineering
  • Industrial equipment

Limitations

VMQ sponge rubber has limited resistance to mineral oils, fuels, concentrated acids and certain solvents. For applications involving continuous exposure to oils or fuels, materials such as NBR, HNBR or FKM are generally more suitable.

Essential for classic rubbers, not needed for TPE, PVC.

EPDM/Silicone → very low. TPE/Foam → higher depending on structure. Important for outdoor applications.

Important for TPE, PVC (more plastic-like). Classic elastomers don’t have a clear yield point.