Premium
Online pressure–volume–temperature measurements of polypropylene using a testing mold to simulate the injection‐molding process
Author(s) -
Wang Jian,
Xie Pengcheng,
Yang Weimin,
Ding Yumei
Publication year - 2010
Publication title -
journal of applied polymer science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.575
H-Index - 166
eISSN - 1097-4628
pISSN - 0021-8995
DOI - 10.1002/app.32070
Subject(s) - materials science , dilatometer , composite material , polypropylene , molding (decorative) , shrinkage , polymer , injection molding machine , mold , volume (thermodynamics) , piston (optics) , mechanical engineering , thermal expansion , thermodynamics , engineering , physics , wavefront , optics
Abstract To obtain accurate prediction of service performance and service life of polymers and to optimize the processing parameters, a modified online measurement was used to measure the pressure–volume–temperature (PVT) properties of polymers under certain processing conditions. The measurement was based on an injection molding machine, and it was used to obtain the PVT data of polymers directly with a special testing mold under normal processing conditions. The PVT properties of a semicrystalline polymer, polypropylene, were measured through both an online testing mold and a conventional piston–die dilatometer. The PVT properties were correlated by a modified two‐domain Tait equation of state. The differences between the two groups of PVT data measured were investigated, and relative differences, especially in the rubbery state because of different cooling or heating measuring modes and sample forms, were observed. Numerical simulations of injection‐molding processes were carried out by Moldflow software with both of the types of PVT data. The resulting online PVT data exhibited improvement in the accurate prediction of shrinkage and warpage. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010