Material guide
Gluing TPU
A rubber-like printing filament and moulded material used for phone cases, seals and flexible parts.
Also called flexible filament, thermoplastic polyurethane, TPE-U.
How TPU behaves when you bond it
The whole point of TPU is that it moves, so a rigid adhesive will crack off. Flexibility is a hard requirement rather than a preference here, and the bond needs to stretch as far as the part does.
TPU is a flexible thermoplastic polyurethane used in mouldings, films and 3D prints. It generally has better wettability than polyolefin TPEs, but formulation, plasticiser, surface texture and repeated strain control long-term peel performance.
Material properties
- Surface energy
- Medium
- Porosity
- Non-porous
- Rigidity
- Flexible
- Maximum service temperature
- 80C
- Normally needs abrading
- Yes
- Normally needs a primer
- No
Surface preparation
Clean with isopropanol where the grade permits, allow complete evaporation and lightly key only if the product maker recommends it. Keep the bond thin and flexible, remove print strings or weak skin, and test the actual TPU after repeated stretching. Avoid a rigid adhesive cliff at the bond edge.
Which adhesives work on TPU
Good
Contact adhesive
Contact adhesive is rated good for this material as an application-level assessment, not as a blanket manufacturer claim. The prepared surface must be sound and consistently keyed where the finish permits. Suitability still depends on the other substrate, joint design and service environment.
Abrade the surface first.
Good
Polyurethane adhesive
Polyurethane adhesive is rated good for this material as an application-level assessment, not as a blanket manufacturer claim. The prepared surface must be sound and consistently keyed where the finish permits. Suitability still depends on the other substrate, joint design and service environment.
Abrade the surface first.
Conditional
Structural acrylic
Structural acrylic is rated conditional for this material as an application-level assessment, not as a blanket manufacturer claim. The prepared surface must be sound and consistently keyed where the finish permits. Use only after a product-specific test on the actual grade and joint.
Abrade the surface first.
Bonding TPU to something else
TPU to Fabric
TPU to Aluminium
TPU to Glass
TPU to Glazed ceramic
TPU to Mild steel
TPU to Painted metal
TPU to Stainless steel
TPU to TPU
Last reviewed 8 October 2026.