Thermoplastic vulcanizates (TPV)
TPV thermoplastic vulcanizates: rubber-like elasticity with thermoplastic processing
TPV are thermoplastic vulcanizates in which a finely dispersed crosslinked rubber phase is distributed throughout a thermoplastic matrix. This structure makes it possible to combine elastic behavior close to that of vulcanized rubber with processing by thermoplastic methods: injection molding, extrusion, coextrusion, blow molding and multi-component molding.
The technical value of TPV lies in combining elastic recovery, low compression set, heat resistance, weatherability and stable processing without conventional vulcanization. This is why TPV is often regarded as a thermoplastic alternative to EPDM rubber for seals, profiles, cuffs, flexible inserts, automotive components, technical housings and parts that must operate for a long time under compression, bending or environmental exposure.
Dynamic vulcanization: how TPV differs from ordinary TPE
In ordinary TPE, elastic behavior is formed mainly through the physical separation of soft and hard phases. In TPV the rubber phase is additionally crosslinked during compounding — this process is called dynamic vulcanization. The result is a material in which the crosslinked elastomeric particles act as a source of elasticity, while the thermoplastic matrix provides melting, forming and reprocessing.
It is precisely this structure that gives TPV better stability under prolonged compression, higher heat resistance and more rubber-like behavior compared with many soft SEBS or TPO compounds. At the same time, TPV retains the processing advantage of thermoplastics: it can be processed without a separate vulcanization stage, allowing complex profiles, molded parts and combined products to be produced while reducing the number of manufacturing operations.
Compression set and long-term shape recovery
One of the key parameters of TPV is residual deformation after compression, or compression set. For seals, gaskets, cuffs, flexible profiles and damping elements, it is important that the material does not merely compress under load but retains its ability to return to the working geometry after prolonged service.
If the material has a high compression set, the seal gradually loses its clamping force, which can lead to loss of tightness, play, noise and ingress of dust, water or air. TPV is often chosen precisely where standard soft TPE no longer provides sufficient service life under prolonged compression, while conventional rubber complicates the manufacturing process.
Heat resistance and performance under aging
TPV usually withstands elevated temperatures and thermal aging better than many standard TPE-S or TPO compounds. This makes it useful for parts that operate near heat sources, in transport systems, industrial equipment, electrical enclosures, ventilation units or in outdoor conditions with temperature fluctuations.
When selecting TPV, it is important to assess not only the maximum temperature but also the load duration, degree of compression, contact with the environment, part thickness, mechanical regime and the permissible change in properties over time. A material that performs well in a short thermal test may behave differently in a real seal that remains under deformation for years and periodically contacts moisture, cleaning agents or technical fluids.
Weatherability, UV exposure and outdoor applications
TPV is often used in outdoor products thanks to its good resistance to moisture, ozone, temperature fluctuations and atmospheric aging. In profiles, seals, trims, protective elements and automotive parts, the material must retain its elasticity, color, surface and geometry under prolonged environmental exposure.
For parts exposed to solar radiation, it is necessary to take into account UV stabilization, the pigment system, product thickness, surface temperature and expected service life. TPV can be a strong solution for outdoor elastic elements, but the specific grade must match the actual service conditions, not just the general material description.
Chemical resistance and contact with technical media
TPV can offer good resistance to water, weak aqueous solutions, some cleaning agents, ozone and many media in which EPDM-type rubber systems have traditionally been used. This makes it useful for seals, profiles, technical inserts, housing zones and parts that operate in contact with a humid or atmospheric environment.
At the same time, TPV cannot automatically be considered resistant to all oils, fuels, solvents or aggressive technical fluids. For parts in contact with lubricants, fuels, hydraulic fluids, cleaning concentrates or chemical agents, it is necessary to verify the compatibility of the specific grade with the specific medium, temperature, contact time and level of deformation.
TPV in profiles, seals and extrusion
Profile extrusion is one of the key application areas of TPV. The material is used for seals, flexible profiles, protective edges, decorative inserts, tubing, sleeves, technical sealing zones and multilayer products. In such processes, profile stability, uniform thickness, shrinkage control, surface quality, absence of tackiness and geometric stability after cooling are important.
For coextrusion, TPV can be combined with rigid thermoplastics, creating combined profiles with a soft sealing or protective zone. In such products, layer compatibility, adhesion, similar shrinkage, temperature regime, contact geometry and material behavior after cooling are critical. An incorrectly selected material pair can result in delamination, waviness, profile distortion or loss of tightness.
Injection molding, overmolding and combined parts
TPV is also used in injection molding to produce sealing inserts, cuffs, trims, flexible housing elements, dampers, protective parts and combined products. The material can be useful in parts that require elasticity, stable shape, soft contact, damping or sealing without a separate rubber operation.
In overmolding, it is important to assess the adhesion of TPV to the rigid polymer, the molding temperature, surface condition, pressure, cooling time and bonding geometry. Not every TPV adheres equally well to PP, PE, ABS, PC, PA or PBT. If adhesion is insufficient, the soft layer may delaminate, lose tightness or fail at the edge during service.
TPV compared with rubber, TPO, TPE-S and TPU
Compared with vulcanized rubber, TPV offers the advantage of thermoplastic processing: a shorter cycle, the possibility of molding or extrusion on standard equipment, fewer operations, potential recyclability and easier integration with rigid plastics. However, in applications with extremely low compression set, very high temperatures or aggressive chemistry, special rubber systems may remain the better solution.
Compared with TPO, TPV usually performs better under prolonged compression, elevated temperature and in conditions requiring more rubber-like behavior. TPO can be lighter, cheaper and sufficient for less loaded flexible parts, but TPV is more often chosen for seals, profiles and technical elements with higher service-life requirements.
Compared with TPU, TPV is usually inferior in wear resistance, tensile strength and abrasion endurance, but it can be better for seals, outdoor profiles, weather-resistant parts and applications where EPDM-like behavior is important. Compared with TPE-S, TPV more often has better heat resistance, compression set and long-term stability under technical conditions.
Typical TPV applications
TPV is used in parts that require elasticity, stable shape recovery, heat resistance and the possibility of thermoplastic processing:
seals, gaskets, cuffs and flexible sealing elements;
extrusion profiles, protective edges, decorative and technical inserts;
automotive interior and exterior parts with weatherability requirements;
flexible housing elements, trims, dampers and cushioning zones;
coextrusion and multilayer profiles with a soft sealing section;
parts for household appliances, industrial equipment and technical systems;
products where EPDM or other rubber needs to be replaced with a thermoplastic solution;
elastic elements operating under prolonged compression, bending or temperature fluctuations.
Critical parameters for TPV selection
For the correct selection of TPV, it is necessary to evaluate not only the Shore hardness but the full technical function of the part:
Shore A or Shore D hardness and the actual elastic behavior;
compression set at the operating temperature and compression duration;
operating temperature range and stability after aging;
resistance to water, ozone, UV radiation and atmospheric factors;
contact with cleaning agents, lubricants, technical fluids or other media;
requirements for extrusion, profile stability, surface and shrinkage;
adhesion during overmolding or coextrusion with rigid polymer materials;
sealing geometry, wall thickness, degree of compression and permissible deformation;
the need for color stability, matte finish, gloss or a special surface;
the product economics compared with rubber, TPO, TPE-S, TPU or TPEE.
TPV selection by Material Wizard
Material Wizard selects TPV based on the actual performance of the part: hardness, compression set, temperature, environment, weatherability, processing method, profile requirements, sealing geometry, adhesion to other materials and serial production stability.
This approach makes it possible to determine whether TPV is indeed needed, or whether it is more appropriate to consider TPO, TPU, TPE-S, TPEE, PEBA or conventional rubber. For the manufacturer, this means not just choosing an elastic pellet but a technically justified solution for a seal, profile, cuff, trim, coextruded part or flexible element with predictable service life.