Open AccessPrediction of foamability of polyethylene terephthalate using viscous and elastic parameters
Author(s) -
Yang Zhaoping,
Xin Chunling,
Mughal Waqas,
Wang Zeming,
Bai Xue,
He Yadong
Publication year - 2018
Publication title -
advances in polymer technology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.523
H-Index - 44
eISSN - 1098-2329
pISSN - 0730-6679
DOI - 10.1002/adv.21910
Subject(s) - materials science , polyethylene terephthalate , rheology , viscoelasticity , composite material , strain hardening exponent , hardening (computing) , viscosity , layer (electronics)
Rheological behavior and foamability of polyethylene terephthalate ( PET ) with different molecular structures were investigated. The aim of this study was to find out the viscous and elastic parameters which can predict the foaming properties of PET . It is found that the foams of strain hardening PET have high expansion ratios and fine cell morphologies. This is correlated with the contribution of strain hardening to the improvement of melt strength and failure strain during elongational experiments. Basing on the fact that foamability of a material is governed by its strain hardening (a pure elastic behavior), a viscous parameter (complex viscosity), and an elastic parameter (loss tangent) obtained from dynamic shear rheology are well linked to the expansion ratios of foams. These two parameters formed an optimized viscoelastic window, which is suitable for foaming. This means the foamability of PET can be determined by viscous and elastic parameters without consideration of molecular constitution.