Premium
On‐Line measurement of parison geometry during blow molding: Parison swelling for three high‐density polyethylenes with different molecular weights and molecular weight distributions
Author(s) -
Eggen Svein,
Sommerfeldt Arne
Publication year - 1996
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.10420
Subject(s) - blow molding , materials science , extrusion , molding (decorative) , high density polyethylene , composite material , swell , polymer , polyethylene , compression molding , extrusion moulding , mechanical engineering , thermodynamics , mold , engineering , physics
An image analysis technique has been developed to measure diameter and thickness distribution of a parison during the extrusion stage in blow molding. The system operates on‐line during extrusion on any commercial blow‐molding machine. The system has been developed to help development of new blow‐molding resins by increasing our understanding of the connection between polymer structure and parison shape. The system can also be used for die design during optimization of a production process. The combined use of experimental design and multivariate projection techniques makes this an efficient tool for the practical processing engineer. Experiments done on three high‐density polyethylene blow‐molding resins show the importance of measuring the time dependence of the diameter and thickness distribution under different extrusion conditions for a given polymer. Our results show that many of the swell and sag related properties we see cannot be directly inferred from standard laboratory swell‐experiments.