Surface tensions of epoxy and polyurethane based primers in liquid state and surface energies of fully cured
| Primer type | Surface tension (liquid, mN/m) | Surface energy (cured film, mN/m) |
|---|---|---|
| Epoxy-based primer (liquid state) | ∼25–30 mN/m (typical; e.g. ∼28.9 mN/m @ 20 °C) | – (not applicable for liquid) |
| Epoxy-based primer (cured film) | – (not applicable for solid) | ∼40–50 mN/m (typical; e.g. ∼45 mN/m) |
| Polyurethane-based primer (liquid state) | ∼25–35 mN/m (typical formulation) | – (not applicable for liquid) |
| Polyurethane-based primer (cured film) | – (not applicable for solid) | ∼30–46 mN/m (varies depending on formulation) |
| Primer type | Surface tension (liquid, mN/m) | Surface energy (cured film, mN/m) |
|---|---|---|
| Epoxy-based primer (liquid state) | ∼25–30 mN/m (typical; e.g. ∼28.9 mN/m @ 20 °C) | – (not applicable for liquid) |
| Epoxy-based primer (cured film) | – (not applicable for solid) | ∼40–50 mN/m (typical; e.g. ∼45 mN/m) |
| Polyurethane-based primer (liquid state) | ∼25–35 mN/m (typical formulation) | – (not applicable for liquid) |
| Polyurethane-based primer (cured film) | – (not applicable for solid) | ∼30–46 mN/m (varies depending on formulation) |