Premium
Rheology of polymer melts in high shear rate
Author(s) -
Takahashi Hideroh,
Matsuoka Takaaki,
Kurauchi Toshio
Publication year - 1985
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.1985.070301214
Subject(s) - shear rate , rheology , materials science , newtonian fluid , polymer , polystyrene , rheometer , shear (geology) , shear flow , non newtonian fluid , thermodynamics , polymer chemistry , composite material , physics
Little is known of the rheology of polymer melts in the high shear rate up to 10 6 s −1 or more. A specially designed high‐shear‐rate rheometer was developed, by which the rheology of polymer melts for shear rates up to 10 8 s −1 can be investigated. Two non‐Newtonian regions and a transition or the second Newtonian region were observed in the wide range of shear rates up to 10 7 s −1 . The observed flow curves for various polymer melts are classified into three typical patterns. One is the flow curve typically shown of high‐density polyethylene in which a clear second Newtonian region appears after the first non‐Newtonian region. The second is the typical flow curve of polystyrene in which a “transition region” appears instead of the second non‐Newtonian region. The third is the flow curve shown of acrylonitrile‐styrene copolymer, which exhibits behavior between the two types. A generalized flow curve is proposed to explain the observed flow behaviors of various polymers over a wide range of shear rates. The flow behavior in high shear rate results from high orientation and scission of polymer molecules.