Effect of Different Air Intake Angles on Gas⁃assisted Extrusion of Sheet Polymer

doi:10.19491/j.issn.1001-9278.2021.07.014

Abstract

Abstract:

In this work， a sheet polymer extrusion experiment was conducted on the basis of the vertical and parallel air intake separately though a gas?assisted extrusion technology. A three?dimensional model was established based on rheological principles， and a finite element method was applied to the numerical simulation of gas?assisted extrusion molding under the different air intake angles of 0°， 15°， 30°， 45°， 60° and 90°. The experimental results indicated that a change in air intake angle generated different effects on the gas?assisted extruded products. There was a largest degree of deformation in the melt in the die under an air intake angle of 90°. As the air intake angle decreased， the melt deformation was weakened. The air inlet angle of 15°~30° is most beneficial to the gas?assisted extrusion molding of polymer sheets.

Key words: gas?assisted extrusion, rheology, air intake angle, numerical simulation

CLC Number:

TQ320.66⁺3

WANG Ruizhe, LIU Hesheng, HUANG Xingyuan, YU Zhong, JIANG Shiyu, LIU Tongke. Effect of Different Air Intake Angles on Gas⁃assisted Extrusion of Sheet Polymer[J]. China Plastics, 2021, 35(7): 80-86.

Figures/Tables 11

Fig.1. Schematic diagram of each sheet extrudate segment

Fig.2. Boundary setting of 3D gas intake model

Fig.3. FEM for mesh model

样品	$η 0$ /Pa·s	$λ$ /s	$ε$	$ξ$	s
PP	4 688	0.1	0.15	0.44	0.111 1
气体	26.36 $× 10 - 6$	0	0	0	0

样品	$η 0$ /Pa·s	$λ$ /s	$ε$	$ξ$	s
PP	4 688	0.1	0.15	0.44	0.111 1
气体	26.36 $× 10 - 6$	0	0	0	0

Tab.1. Material parameters of polymer melt and gas

Fig.4. Gas assisted extrudate experimental process

Fig.5. Sheet polymer products of GAE

Fig.6. Variation of pressure difference between the surface and center of polymer melt

Fig.7. vx distribution of the interface between melt and gas

Fig.8. vy distribution of the interface between melt and gas

Fig.9. vz distribution at the center of polymer melt and gas

Fig.10. Shear rate distribution of the interface between melt and gas

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