Extrusion & Post
7 visualizações
LLDPE Blown Film Melt Fracture
Fenómeno do problema
The film surface is overall orange-peel-like and thread-like rough, more severe than sharkskin.
Análise das causas
The outlet shear rate far exceeds the critical value, and the melt becomes overall unstable; low die temperature and excessive output are the main causes.
Solução
① Reduce output/line speed; ② raise the die temperature; ③ enlarge the die lip gap to reduce shear; ④ use PPA; ⑤ check whether there are abrupt changes in the die flow channel.
Conclusão principal
For melt fracture, first reduce shear, then raise temperature.
Isto foi útil?
0 pessoas acharam isto útil
Obrigado pelo seu comentário!