Overmolding depends on the TPE grade, substrate, part and mold design, material preparation and processing conditions. Two-step and two-shot molding should be selected for the product rather than ranked as universally better or worse.
Melt temperature, substrate temperature and injection speed affect contact and adhesion. Adjust them within the selected materials’ processing windows, considering filling, flash, substrate distortion and degradation.
Moisture, contamination and mold release on the substrate may affect adhesion. Drying and preheating requirements should follow the technical information for the specific TPE and substrate.
Record trial settings and evaluate adhesion and finished-part performance before establishing repeatable processing conditions.