Resin Data
TPE
Elastómero Termoplástico
TPE·Thermoplastic Elastomers·Variable
TPE (Thermoplastic Elastomer) is the "bridge" between plastics and rubbers: it processes by injection like a conventional thermoplastic (no vulcanization, no press molds, cycles in seconds), but the finished part behaves like rubber —Shore A 30-95, elastic recovery, soft-touch, sealing. Under the generic name "TPE" live seven chemically distinct families classified by ISO 18064, each with different properties and uses.
The seven TPE families:
- TPE-S (Styrenic, SBS/SEBS) — the most used globally. Dominant brand: Kraton.
- TPE-O (Thermoplastic Polyolefin) — PP+EPDM blends.
- TPE-V (Thermoplastic Vulcanizate) — dynamically vulcanized PP+EPDM. Brand: Santoprene (Celanese, ex-ExxonMobil).
- TPE-U (Thermoplastic Polyurethane).
- TPE-A (Thermoplastic Polyamide) — Arkema Pebax.
- TPE-E or COPE/TPEE (Copolyester) — brand: DuPont Hytrel.
- TPZ — miscellaneous category for everything else.
Major global producers: Kraton (SBC leader), Celanese (Santoprene TPV), BASF, Covestro (TPU), DuPont (Hytrel), Arkema (Pebax). Flagship applications: soft-touch overmolding (tool grips, toothbrushes, handles), automotive seals and gaskets, safe PVC-free toys, non-DEHP medical components, shoe soles. Which specific TPE do you process? Share your experience in the comments.
The ranges shown in these data tables were compiled by the MVPS team from various parameter sheets and literature, integrating the lower and upper limits for each material type.
This information must be carefully reviewed when developing injection molding processes. Final ranges and processing tolerances are the responsibility of the engineer in charge.
These ranges are not recommended for developing specific process tolerances. MVPS always recommends requesting and consulting the supplier's data sheet.
General Properties
| Chemical Structure | Variable |
| Specific Gravity (Density) | 1.17:1 |
| L/D Ratio | 18 – 24 |
| Compression Ratio | 2.5 – 3.5 |
| Tonnage Factor | 3.86 – 5.41kN/cm² |
| Thermal Diffusivity | 0.1473mm²/s |
| Max Shear Rate | 20,0001/s |
| Shrinkage | 1 – 2% |
| Regrind | 20% |
| Heat Deflection (HDT) @ 1.82 MPa | 45°C |
| Glass Transition (Tg) @ 10°C/min | -20°C |
| Vicat Softening @ 50N | 75°C |
Drying
| Drying Temperature | 49 – 60°C |
| Drying Time | 1 – 6h |
| Recommended Moisture | 0.1% |
| Recommended Dryer Type | Desiccant |
| Dew Point | -40°C |
Temperatures
| Melt | 221 – 241°C |
| Nozzle | 221 – 241°C |
| Front | 221 – 241°C |
| Middle | 199 – 221°C |
| Rear | 179 – 199°C |
| Demolding | 46 – 57°C |
| Mold (Cooling) | 29 – 46°C |
| Feed Throat | 35 – 79°C |
Processing
| Back Pressure | 10.3 – 15.2bar |
| Screw Speed | 20 – 80RPM |
| Injection Speed | Medium – High |
| Barrel Occupancy | 30 – 75% |
| Injection Pressure | 350 – 1,500Pbar |
| Holding Pressure | 88 – 1,200Pbar |
| Cushion | 5.1 – 12.7mm |
Mold
| Runner Diameter | 4.06 – 7.11mm |
| Gate Diameter | 1.02 – 1.52mm |
| Gate Area | 0.81 – 1.82mm² |
| Wall Thickness | 0.51 – 3.81mm |
Venting
| Depth (Vent Depth) | 0.0203 – 0.0508mm |
| Land (Vent Land) | 0.508 – 1.52mm |
| Width (Vent / Clearance) | 3.05 – 12.7mm |
| Relief (Relief Channel) | 0.2032 – 0.4064mm |
Frequently asked questions
A **TPE** (Thermoplastic Elastomer) is a material combining:
- **Rubber behavior** in use: Shore A 30-95, elastic recovery on deformation, soft-touch, sealing.
- **Thermoplastic behavior** in process: melts with heat, flows in molds, **reprocesses** and recycles.
**Key difference vs vulcanized rubber** (EPDM, NBR, pressed silicone): rubber has **permanent chemical crosslinks** —once vulcanized it doesn't melt, doesn't flow, doesn't recycle. TPE has no permanent chemical crosslinks (except TPV with partial ones) but a **physical microstructure** that in cold behaves like an elastic network but breaks down and flows on heating. Result: injection cycles of **20-60 seconds** vs 5-15 minutes for vulcanized rubber.
**ISO 18064** classifies TPEs into seven chemical families:
- **TPS (TPE-S)**: styrenic, SBS and SEBS. World's best-sellers, base of soft-touch grips. Brand: **Kraton**.
- **TPO (TPE-O)**: PP blends with elastomer (EPDM, POE). Auto exterior trim, bumpers.
- **TPV (TPE-V)**: dynamically vulcanized PP+EPDM. Premium automotive seals. Brand: **Santoprene**.
- **TPU (TPE-U)**: polyurethane. Soles, hoses, coatings.
- **TPA (TPE-A)**: PA+polyether. Elite athletic footwear, catheters. Brand: **Pebax**.
- **TPC (TPE-E / COPE / TPEE)**: copolyester (PBT+polyether). Brand: **Hytrel** (DuPont).
- **TPZ**: miscellaneous (includes TPI, special TPO).
**SEBS-based TPE-S** (Kraton, Monprene, Tekron) is the world standard:
- **Excellent soft-touch** Shore A 30-70.
- **Direct chemical adhesion** to PP, ABS, PC, PA substrates via 2-shot injection or insert molding.
- **Easy processing**: low temperature 170-210°C, fast cycles.
- **Low cost**: $3-8/kg vs $8-15/kg equivalent TPU.
- **No phthalates or PVC** —compliance with modern regulations (REACH, Prop 65).
Typical applications: toothbrush handles (Oral-B, Colgate), tool grips (Stanley, Bosch), razor handles (Gillette), racket grips, **electronic product handles** (3D printers, cameras).
Varies by family:
- **TPE-S (SBS/SEBS)**: optional drying 60-80°C × 1-2h, melt **170-210°C**, mold 20-40°C.
- **TPO**: usually no drying, melt **200-240°C**, mold 20-40°C.
- **TPV (Santoprene)**: optional drying 60-80°C × 1-3h, melt **180-230°C**, mold 20-50°C.
- **TPU**: mandatory drying 80-100°C × 2-4h, melt **180-220°C**, mold 20-40°C.
- **TPA (Pebax)**: drying 80°C × 4-6h, melt **220-260°C**, mold 20-40°C.
- **TPC (Hytrel)**: drying 100°C × 2-3h, melt **220-260°C**, mold 30-50°C.
**Common rule**: cold mold 20-40°C (opposite of engineering plastics), medium-high injection speed.
**LSR** (Liquid Silicone Rubber) is a thermoset with its own advantages:
- **TPE wins on**: **cost** (3-5× cheaper), **fast injection cycles** (20-60s vs LSR 60-180s), **recyclability**, processing on conventional machines without dedicated equipment.
- **LSR wins on**: **temperature** (continuous use 200°C vs TPE max ~120°C generally), **implantable biocompatibility**, **low temperatures** (-50°C+ without becoming rigid), nearly total chemical inertness, natural transparency.
**2026 rule**: for **consumer soft-touch, automotive seals, handles** → **TPE**. For **implantable medical, high-temperature parts, microfluidics** → **LSR**.
**TPV** (Thermoplastic Vulcanizate) is a blend of **polypropylene (PP) + EPDM rubber**, where the EPDM is **dynamically vulcanized** during mixing (partial chemical crosslinks forming in the elastomeric phase dispersed in the PP matrix). Result:
- **Low compression set** (15-30% at room temperature, comparable to vulcanized rubber) —TPE-S and other TPEs lose 40-60% in permanent deformation.
- **High continuous temperature resistance** (HDT ~125°C).
- **UV, ozone, and chemical resistance** better than TPE-S.
Dominant brand: **Santoprene** (Celanese, ex-Advanced Elastomer Systems, ex-ExxonMobil). Applications: **automotive door and window seals** (replaced EPDM in many OEMs), **CV joint boots**, **airbag components**, **premium comfort-grip handles**.
**Yes, specific grades are**:
- **Toys**: TPE-S and TPV are **modern substitutes for PVC with phthalates** in soft toys. Meet **EN 71** (Europe) and **ASTM F963** (USA). Brands like **Lego** use TPE-S for gaskets, **Fisher-Price** for soft toys, **Manhattan Toy** for teethers.
- **Food contact**: there are specific TPE-S, TPV, and TPC grades meeting **FDA 21 CFR**, **EU 10/2011**. Applications: lids with elastic seals (preserve jars), bottle nipples (mostly silicone, but some TPE), kitchen utensil grips.
**Important**: **not all grades** are toy-safe or food-grade. Verify the **specific datasheet** for EN 71-3 and FDA compliance before use.
**Varies significantly by family**:
- **TPE-S (SBS/SEBS)**: 1.5-3.0% (high, due to elastomer).
- **TPO**: 1.5-2.5%.
- **TPV (Santoprene)**: 1.5-3.0%.
- **TPU**: 0.5-2.0% (heavily depends on Shore A).
- **TPA (Pebax)**: 0.8-2.5%.
- **TPC (Hytrel)**: 1.0-2.5%.
**High shrinkage** is common characteristic of TPEs —the elastomeric component shrinks more than a rigid plastic on cooling. For dimensional parts (precision-fit seals), careful oversize mold design and cavity-by-cavity validation.
**Two common issues**:
- **(1) Family-specific drying**: TPU, TPA, and TPC are **hygroscopic** and need rigorous drying. TPE-S and TPV are **non-hygroscopic** and don't require it (some benefit). Confusing them and over-drying a TPE-S generates **property loss from degradation**.
- **(2) Overmolding compatibility**: to overmold TPE on rigid substrate (PP, ABS), the grade must be **designed for that adhesion**. Generic TPE-S **doesn't adhere well to PA or PC** —specific grades needed (Kraton G + adhesion promoters). Insert molding in new projects requires **pull-strength test** before production.
**Yes, that's its great advantage over vulcanized rubber**. All pure thermoplastic TPEs (TPE-S, TPO, TPU, TPA, TPC) are **mechanically recyclable** —ground, melted, and reinjected without significant property loss. **Partial exception**: TPV has partial chemical crosslinks from dynamically vulcanized EPDM, reducing recycling to 15-25% max regrind.
**Comparison with vulcanized rubber**: vulcanized EPDM/NBR/silicone rubber **can't be recycled** thermo-mechanically —only ground as filler for asphalt. TPE allows **100% scrap recovery** in injection, an important economic and sustainability advantage.
Sources
- Teknor Apex — TPE Comparison Guide (TPO vs TPV vs TPU vs TPR)· Teknor Apex
- Xometry — 7 Types of Thermoplastic Elastomers· Xometry
- Kraton Corporation — Consumer Products SBC· Kraton
- ExxonMobil/Celanese — Santoprene Injection Molding Guidelines (PDF)· ExxonMobil / Celanese
- Thermoplastic Elastomer (Wikipedia)· Wikipedia