A thermoplastic elastomer (TPE) bridges that gap. It is a family of materials, not one chemical formula, that behaves like rubber in use and processes like plastic in the factory. Indian demand is growing too: MarketsandMarkets projects the Indian TPE market at USD 897 million in 2025, rising to USD 1,260.6 million by 2030.
This guide covers how TPEs work, the main families, properties, applications, processing, limits and grade selection.
Key Takeaways
- TPEs pair rubber-like recovery with injection moulding and extrusion.
- Hard and soft phases create the behaviour, linked chemically or by compounding.
- TPS, TPU, TPV, TPO, TPC and TPA suit different performance needs.
- Grade choice depends on hardness, temperature, chemicals, compression set, process and compliance.
What Is a Thermoplastic Elastomer?
A TPE is an elastomeric polymer that softens and flows when heated, then regains useful elastic properties on cooling. ISO 18064:2022 describes it as a polymer or blend with vulcanised-rubber-like properties at service temperature. It can be processed and reprocessed at elevated temperature like a thermoplastic.
The name looks contradictory, but it isn't. "Thermoplastic" describes how the material is processed. "Elastomer" describes its ability to deform and recover.
Plastic, rubber, or both?
TPEs are generally classed as plastics because they are processed thermoplastically. They are engineered to give rubber-like flexibility and resilience.
How TPE compares
| Material | Response to heat | Crosslinking |
|---|---|---|
| Conventional thermoplastic | Softens, reshapes repeatedly | None; usually rigid |
| Thermoset rubber | Does not remelt once cured | Chemical crosslinks formed during curing |
| TPE | Softens and reprocesses | Physical (reversible) in most; TPV is a special case |
Not all TPEs are alike. Hardness, elasticity, heat and chemical resistance, and recyclability vary widely by family, formulation, additives and grade.
How TPE Structure Creates Rubber-Like Behaviour
Most TPEs combine two kinds of domains:
- Hard domains give shape retention, strength, processability and temperature performance.
- Soft domains give flexibility, elasticity, low-temperature performance and a softer feel.
Hard domains act as physical crosslinks. When the material is cool they hold the structure together, so it stretches and recovers.
Heat disrupts them, so the material flows and can be moulded. Cooling restores them. HEXPOL describes this reversible physical crosslinking as the basis for reprocessing its compounds.
TPVs are the exception worth knowing. Dynamic vulcanisation produces a highly crosslinked rubber phase finely dispersed in a continuous thermoplastic matrix. So "TPEs contain no chemical crosslinks" is wrong for TPV.
How Do TPEs Work? Structure, Types, and Processing
Two structural routes
- Block copolymers: hard and soft segments sit in the same polymer chain.
- Blends: a thermoplastic and an elastomer are compounded together.
The main families
- TPS (SBC): styrenic block copolymers, valued for softness, elasticity, adhesion and formulation flexibility. Elastron lists grades from 20A to 60D.
- TPU: polyurethane types chosen for abrasion resistance, toughness and strength. BASF's Elastollan range spans 50A to 75D.
- TPV: used where rubber-like sealing and durability are needed with thermoplastic processing. Elastron lists 35A to 50D.
- TPO: polyolefin types valued for light weight, impact and chemical resistance. HEXPOL blends are typically above 80A.
- TPC (TPE-E): copolyesters for fatigue resistance, strength, heat performance and dimensional stability. Hytrel runs 30D to 80D.
- TPA (TPE-A): polyamide elastomers combining flexibility, low weight, temperature performance and chemical resistance.
These hardness figures are supplier ranges, not family limits. A and D are different scales.
The processing cycle
Pellets are heated until they flow, shaped in a mould or die, then cooled so the material regains its structure.
- Injection moulding: discrete, precise 3D parts.
- Extrusion: continuous profiles and tubing.
- Blow moulding: hollow components.
- Overmoulding or two-component moulding: soft-touch or hard-soft assemblies. PP/TPE is well established; PA, PC and ABS substrates need specifically matched formulations.
Moisture matters for some families. BASF specifies TPU water content below 0.02%, and Arnitel PL650 (a TPC) at or below 0.05 wt%. Drying settings belong to the specific material, not the family.
Fillers, plasticisers, colourants, stabilisers and flame retardants change performance, regulatory status and end-of-life options.
What Are the Properties, Benefits, and Limitations of TPE?
Properties to review
- Hardness, tensile strength, elongation, tear resistance
- Resilience and abrasion resistance
- Compression set and permanent deformation
Hardness is usually quoted on Shore scales (ISO 868, ASTM D2240), and no simple conversion exists between A and D. A softer grade isn't automatically better. For load-bearing, sealing or durable parts, a harder grade with better compression set may win.
Benefits
- Many grades need no conventional rubber curing step
- Work on injection moulding and extrusion equipment
- Easy to colour, with wide design freedom
- Can be overmoulded onto compatible rigid substrates
Chemical and environmental performance
Grades can be designed for resistance to oils, fuels, cleaning agents, UV, moisture or temperature. Confirm each for the specific formulation and exposure. For example, aromatic hydrocarbons swell TPU, and polyester TPU can hydrolyse in prolonged hot, wet service while polyether TPU resists better.
Limitations
- Some grades have lower continuous-use temperature than thermoset rubbers
- Creep and compression set can appear under sustained load
- Certain chemicals attack some grades
- Shrinkage and processing sensitivity (Pebax 2533 SD 02 reports 0.6-0.7%, and shrinkage can continue for 48 hours)
TPE versus conventional rubber
TPE suits high-volume moulding, production flexibility and scrap reuse. Rubber may win on sustained heat, chemical exposure and demanding sealing. Temperature ratings from different suppliers use different bases, so compare like with like.
"Recyclable" needs care
Reprocessing production scrap is not the same as recycling a finished, mixed-material product. KRAIBURG allows up to 15% regrind in its compounds, and BASF up to 30% for TPU, both conditional. Finished assemblies depend on available collection and recycling systems.
Why Manufacturers Use TPEs
- Familiar thermoplastic equipment keeps production straightforward
- Hard-soft moulding can cut assembly steps
- Consistent shapes and surface finishes
- Adjustable hardness, colour, grip, cushioning, sealing and vibration damping
A Celanese case study on Santoprene TPV for window and door seals reports shorter cycles, higher throughput, scrap recycling and lower part costs, along with heat-welded profiles without adhesives. The study does not publish numerical savings, so treat the benefits as qualitative until you run your own trials.
Where TPEs May Not Be the Best Choice
Thermoset rubber, silicone, rigid thermoplastics, PVC or other engineering polymers may be better suited where you face:
- Sustained high heat (silicone groups reach roughly 232 °C in Parker's handbook, against 100-135 °C for the TPS and TPV figures quoted)
- Severe chemical or oil exposure
- Extreme compression or long-term demanding sealing
Select from verified test data and the real service environment, not the TPE label alone.
What Are TPEs Used For and How Are They Processed?
| Sector | Typical use | Property exploited |
|---|---|---|
| Automotive | Grommets, seals, mats, interior parts | Elasticity, weather resistance |
| Medical | Tubing, syringe seals, valves, closures | Flexibility, sterilisation compatibility |
| Wire and cable | Extruded sheathing | Flexibility, abrasion resistance |
| Electronics | Dissipative protective parts | Static control |
| Grips and consumer goods | Handles, soft-touch housings | Tactile feel, adhesion, colour |
| Agriculture and industry | Fittings, seals, vibration mounts | Weathering resistance |
| Packaging | Closure liners | Softness, elasticity |
These are supplier-documented uses, not guarantees for every grade.
Processing method shapes the finished part:
- Injection moulding for precise 3D parts
- Extrusion for continuous profiles
- Blow moulding or thermoforming for selected hollow or sheet designs
Compliance note: For food-contact, personal care, healthcare, childcare and drinking-water uses, the grade, additives, processing and finished article must all meet the applicable rules.
In India, FSSAI's 2025 packaging compendium sets overall migration limits of 60 mg/kg or 10 mg/dm² and requires conformity certificates from NABL-accredited laboratories. Overseas declarations (FDA, EU, WRAS) do not replace Indian requirements.
How to Choose the Right TPE for an Application
- Define the service environment. Identify targets for hardness, elongation, compression set, temperature range, UV, moisture, oils, solvents, cleaning agents and loading.
- Match family and process. Confirm whether you need injection moulding, extrusion, blow moulding, overmoulding or welding, and check substrate compatibility.
- Check sourcing and scale-up. Review technical data sheets, samples, tooling, batch consistency, quality controls, lead times and the path from lab trial to production.
- Validate before approval. Test hardness, tensile and tear behaviour, compression set, ageing, chemical exposure, adhesion, dimensional stability and any food, medical or electrical requirements.
Teams evaluating advanced polymers can work with Distil, which lists TPU, TPO and TPEE in its catalogue. Its R&D team, led by Dr. Leema Joseph, supports application-specific grade selection and technical trials. Distil supplies samples and technical data sheets, and coordinates scale-up through a single point of contact and a partner manufacturing network.
Frequently Asked Questions
What are thermoplastic elastomers used for?
Common uses include seals, grips, soft-touch parts, tubing, automotive components, consumer products, wire and cable, packaging and medical items. The right grade depends on performance and compliance needs.
Is thermoplastic elastomer a plastic?
TPEs are processed as thermoplastics but formulated for rubber-like elasticity. They combine traits of conventional plastics and elastomers.
Are thermoplastic elastomers safe?
It depends on the formulation, additives, intended use and regulations. Food-contact, medical, childcare and personal care uses need tested, compliant grades.
Which is better, rubber or TPE?
TPE offers easier processing, design flexibility and reprocessable scrap. Rubber can win under sustained heat, chemical exposure or demanding sealing. The application decides.
Which is better, TPE or PVC?
They differ in flexibility, hardness, processing, chemical performance and regulation. Flexible PVC relies on plasticisers, including some phthalates that ECHA restricts. Neither is universally superior; match the material to end-use needs.
