Freeze Thaw Void (FTV)
What is FTV?
FTVs are voids that typically occur while the adhesive is frozen and incapable of absorbing stresses resulting from differential shrinkage/expansion of the adhesive, syringe and piston. This is often followed by a sharp crack. As the adhesive thaws, sporadic wet‐out between the adhesive and syringe wall occurs, entrapping air. As the adhesive fully thaws, the entrapped air coalesces to form air bubbles located between the adhesive and syringe wall. FTVs can typically be observed through the syringe wall.
How to prevent FTVs?
- Avoid touching with bare hands as the human hand is warm. Use gloves.
- Hold syringe by the ends instead of the barrel.
- Avoid temperature shocks. Do not apply heat when thawing. Thaw at ambient condition.
- Thaw syringes in original packaging before handling.
- Use a thawing rack to thaw.
How long to thaw?