Analysis of Bubble Growth in Supercritical CO2 Extrusion Foaming Polyethylene Terephthalate Process Based on Dynamic Flow Simulation
- Resource Type
- Authors
- Zhenhao Xi; Ling Zhao; Shun Yao; Yijie Ling; Yichong Chen; Dongdong Hu
- Source
- Polymers
Volume 13
Issue 16
Polymers, Vol 13, Iss 2799, p 2799 (2021)
- Subject
- Materials science
Polymers and Plastics
Bubble
Plastics extrusion
Organic chemistry
General Chemistry
Cell morphology
Article
bubble growth
Supercritical fluid
supercritical CO2
Condensed Matter::Soft Condensed Matter
Physics::Fluid Dynamics
chemistry.chemical_compound
QD241-441
Rheology
chemistry
dynamic melt flow
Polyethylene terephthalate
Extrusion
Composite material
PET extrusion foaming process
Melt flow index
- Language
- ISSN
- 2073-4360
Bubble growth in the polymer extrusion foaming process occurs under a dynamic melt flow. For non-Newtonian fluids, this work successfully coupled the dynamic melt flow simulation with the bubble growth model to realize bubble growth predictions in an extrusion flow. The initial thermophysical properties and dynamic rheological property distribution at the cross section of the die exit were calculated based on the finite element method. It was found that dynamic rheological properties provided a necessary solution for predicting bubble growth during the supercritical CO2 polyethylene terephthalate (PET) extrusion foaming process. The introduction of initial melt stress could effectively inhibit the rapid growth of bubbles and reduce the stable size of bubbles. However, the initial melt stress was ignored in previous work involving bubble growth predictions because it was not available. The simulation results based on the above theoretical model were consistent with the evolution trends of cell morphology and agreed well with the actual experimental results.