Material Drying
2 views
Silver streaks appearing on PETG injection molded products
Problem Phenomenon
Silver or white filamentary streaks (silver streaks) appear on the surface of PETG products, accompanied by surface roughness.
Cause Analysis
Raw material moisture content is too high (>0.05%) and evaporates at high temperature producing silver streaks; there is air in the barrel (insufficient back pressure); material degradation produces gas.
Solution
Ensure full drying to moisture <0.01%; increase back pressure to 0.5-1.0MPa to vent air; reduce barrel temperature and shorten residence time.
Key Takeaway
PETG silver streaks mainly originate from moisture and gas; full drying and venting are key.
Was this helpful?
0 people found this helpful
Thank you for your feedback!