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General product and materials information only. This page is not medical advice and does not recommend a product for any patient or setting.
Short answer
A thermoplastic elastomer (TPE) is a polymer built from an elastomeric (rubbery) domain and a non-elastomeric (rigid) domain. It stretches and recovers like rubber but, unlike a permanently crosslinked thermoset such as silicone, can be reprocessed with heat. “TPE” names a family, not one material.
Definition and scope
A 2026 review of device biomaterials in the Journal of Functional Biomaterials describes TPEs as polymers made up of an elastomeric domain and a non-elastomeric domain. It says they combine the elasticity of natural rubber with the mechanical strength of thermoplastics, and that they can be made in three ways: as copolymers of elastic and non-elastic blocks, as elastomers with dynamic crosslinks, or as blends of rubber with a thermoplastic.
The same review notes TPEs are used well beyond medicine, in sectors such as automotive, construction and electronics. For lab and clinic staff the practical consequence is that a datasheet, not the three letters “TPE”, identifies what a component is actually made of.
How it works: why a rubbery plastic can be reprocessed
The two domains do different jobs. The elastomeric domain supplies flexibility and elasticity; the non-elastomeric domain supplies the durability and thermal stability of a thermoplastic. Because the structure is thermoplastic rather than permanently crosslinked, the review describes TPEs as reprocessable, in contrast to silicone, which it calls a permanently crosslinked thermoset that is neither biodegradable nor recoverable at end of life.
Types of thermoplastic elastomer
TPEs are classified into two main categories, with further families beyond them.
| Family | Description |
|---|---|
| TPO (thermoplastic olefin) | Main category; the rubber phase is not crosslinked. |
| TPV (thermoplastic vulcanizate) | Main category; the rubber phase is crosslinked. |
| TPNR (thermoplastic natural rubber) | Further category. |
| SBC (styrene block copolymer) | Further category. |
| PEBA (polyether block amide) | Further category. See Pebax and PEBA. |
| TPU (thermoplastic polyurethane) | Further category; TPU shows higher mechanical properties than other TPE subclasses. See what TPU is and the TPE vs TPU comparison. |
These families offer different advantages through tunable mechanical strength, biocompatibility and resistance, so one subclass’s profile should not be assumed for another. For the olefin side of the family, see the polyolefin guide.
Thermoplastic elastomer properties
Qualitatively, the sourced properties are elasticity and flexibility from the rubbery domain, durability and thermal stability from the rigid domain, and reprocessability. Numbers vary by family and grade, so a figure applies only to the grade it was reported for. Hardness for elastomers is normally specified on a Shore durometer scale; the durometer guide explains how to read it, and ASTM D412 covers tensile testing of rubber and thermoplastic elastomers.
TPE and silicone compared in one review
The 2026 review compares materials for one device type (menstrual cups) and reports these values. They describe the grades discussed there, not TPE or silicone in general.
| Property | TPE (as reported) | Silicone (as reported) |
|---|---|---|
| Tensile strength | 67 MPa | 2-10 MPa |
| Oxygen permeability | about 2-50 Barrer | about 900 Barrer |
| Shelf life | 2-5 years | 5-10 years |
| Polymer structure | Reprocessable thermoplastic | Permanently crosslinked thermoset |
For the silicone side, see types of silicone; for another elastomer family, butyl rubber.
Where it matters for labs, clinics and supply decisions
FDA’s guidance on ISO 10993-1 addresses the biological evaluation of medical devices that contact the body directly or indirectly. It aims to determine the potential for an unacceptable adverse biological response from the component materials of the device, and it incorporates risk-based approaches to decide whether biocompatibility testing is needed, plus chemical assessment recommendations. The evaluated object is the device, so a material name such as “TPE” is not by itself evidence of suitability. A supply decision point that follows from this: ask which TPE family and grade a product uses, and where the manufacturer documents the device’s evaluation.
Common misunderstandings
- “TPE” is not one material. It covers olefin, vulcanizate, styrenic, polyamide-ether and polyurethane families, among others.
- TPE is not the same as silicone. One is a reprocessable thermoplastic; the other is a crosslinked thermoset.
- Published numbers are not a specification. The figures above come from a single device-level comparison (menstrual cups).
FAQ
Is a thermoplastic elastomer the same as silicone?
No. A thermoplastic elastomer is a reprocessable thermoplastic, while silicone is described as a permanently crosslinked thermoset.
Which materials count as thermoplastic elastomers?
The family includes TPO, TPV, TPNR, SBC, PEBA and TPU, among others. Each has its own profile.
Does the word “TPE” show a product has been evaluated for body contact?
No. FDA’s ISO 10993-1 guidance concerns the biological evaluation of the finished device, so the material name alone is not evidence of suitability.
Sources
- Biomaterials in Menstrual Cup Design, Journal of Functional Biomaterials 2026, 17(10):527 (PMC13706572), pmc.ncbi.nlm.nih.gov/articles/PMC13706572, checked 2026-10-30.
- FDA, Use of International Standard ISO 10993-1, “Biological evaluation of medical devices – Part 1”, guidance page, fda.gov, checked 2026-10-30.
