PI-WIKI-POLY-14 · Polymer Science · reviewed 2026-10-31
Polymer Science for Body Jewelry
Critical numbers
BioFlex® ISO 10993Certified as passing the ISO 10993 biological tests [1]
PTFE Coefficient of Friction0.05–0.10 (ASTM D1894)
PTFE USP ClassClass VI grades available
Silicone Shore Hardness Range30A–70A (ASTM D2240)
Silicone Tear Strength25–45 kN/m (ASTM D624 Die B)
Nickel Release (all polymers)None: there is no nickel in a polymer formulation to release
PP-R Glass Transition (Tg)~0°C, so the material sits above Tg at body temperature
PP-R Density0.90 g/cm³ (titanium 4.5, steel 8.0)
PTFE Surface Energy18–20 mN/m, lowest of any body jewelry material
Silicone Elongation at Break300–700% (ASTM D412)
PHA / PLA Degradation TimePHA 6–24 months · PLA 12–36 months
REACH Annex XVII Entry 51DEHP, DBP, BBP, DIBP <0.1% w/w of plasticised material, all articles since 7 Jul 2020 [14]
Do not
- Counterfeit material sold under a real brand name
- Autoclaving tight PTFE assemblies
- Gamma-sterilised polyolefins
- Threaded designs in silicone
- Treating PTFE and PP-R as interchangeable
- Assuming a biopolymer is a substitute
Applicable standards
- European Union — REACH (EC) 1907/2006 is the binding instrument for a polymer article
- United States — FDA does not clear body jewelry; there is no polymer body-jewelry device…
- International standards — ISO 10993 series