Transcription of Blow Molding - Polymer Nanostructures and Nanocomposites ...
1 blow Molding1 blow MoldingSTRETCH- blow MOLDING2 blow MoldingINJECTION- blow MOLDINGNo pinch-off scrapExcellent thickness controlFewer surface defects3 blow MoldingBLOW Molding DEFECTSA xial thickness variations in parisonSurface defects: Mottle, Extrusion Die LinesPinch-off scars, trimming4 blow MoldingPARISON SAGS tress due to parison s own weight: e=lA gA=l gStrain Rate = e e= e3 0=l g3 0 Sag Velocityv= l=l2 g3 0To minimize sag:1. Use short parison2. Use Polymer with ahigh zero-shear viscosity5 blow MoldingNECK RING blow Molding PROCESS6 blow MoldingSTRETCH- blow Molding OFSOFT-DRINK BOTTLES7 blow MoldingBRANCHED VS. LINEAR RHEOLOGYB ranched vs. Linear rheologyBranched have higher 0 Linear 0 0 M5 6 WBranched are more shear-thinningat high (1 n)n = for linearn = for branchedBranched polymers are better blow Molding resins8
