Effect of Gas Counter Pressure on the Surface Roughness, Morphology, and Tensile Strength between Microcellular and Conventional Injection-Molded PP Parts
Abstract
:1. Introduction
2. Experimental
2.1. Materials
2.2. Cavity for Gas Counter Pressure
2.3. Gas Counter Pressure Device
2.4. Instrumentation
3. Results and Discussion
3.1. Microcellular Foaming
3.2. Surface Roughness
3.3. Flow Length Comparison
3.4. Tensile Test
4. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Process Parameters | Solid | Foamed |
---|---|---|
Shot size (cm3) | 20 | 14 |
Melt temperature (°C) | 210 | 210 |
Mold temperature (°C) | 40 | 40 |
Injection speed (cm3/s) | 10 | 10 |
Injection pressure (bar) | 1000 | 1000 |
Packing pressure (bar) | 500 | – |
Back pressure (bar) | 50 | 185~188 |
Screw speed (m/min) | 15 | 15 |
Cooling time (s) | 25 | 30~40 |
SCF content (wt%) | – | 1 |
SCF flow rate (kg/h) | – | 0.131 |
Weight reduction ratio | 10% | |
Injection delay time (s) | 5 | 5 |
GCP (bar) | 50/100/150 | 50/100/150 |
GCP holding time (s) | 0/5/10/20 | 0/5/10/20 |
GCP (Bar) | Holding Time (s) | Cell Size (μm) | Skin Thickness (μm) |
---|---|---|---|
100 | 0 | 74.83 | 0.55 |
10 | 17.63 | 0.49 | |
20 | 13.08 | 0.45 |
GCP (bar) | GCP Holding Time (s)/Ra (μm) | |||
---|---|---|---|---|
0 | 5 | 10 | 20 | |
0 | 37.69 | 17.68 | 15.11 | 8.90 |
10 | 37.00 | 15.04 | 12.96 | 7.66 |
50 | 35.68 | 14.50 | 12.39 | 7.33 |
100 | 34.55 | 14.00 | 11.92 | 7.02 |
Process | Solid | MuCell W/O GCP | Mucell (GCP 100 bar)/Ra (μm) | ||||
---|---|---|---|---|---|---|---|
Position | 0 s | 5 s | 10 s | 20 s | |||
Gate | 2.52 | 49.4 | 37.02 | 15.49 | 12.11 | 9.08 | |
Mid | 2.71 | 47.37 | 34.55 | 14.00 | 11.92 | 7.06 | |
End | 4.84 | 45.69 | 30.78 | 12.37 | 9.88 | 7.04 | |
Average Surface Roughness | 3.36 | 47.49 | 34.12 | 13.95 | 11.30 | 7.73 |
Holding Time (s) | Tensile Strength (MPa) | Elongation (%) | Young’s Modulus (MPa) | STD | |
---|---|---|---|---|---|
Mucell without GCP | 24.33 | 12.77 | 21.78 | 0.6 | |
GCP 50 bar | 0 | 19.14 | 10.88 | 15.07 | 0.13 |
5 | 22.53 | 16.92 | 18.67 | 0.10 | |
10 | 22.81 | 18.01 | 18.88 | 0.06 | |
20 | 23.81 | 13.98 | 21.50 | 0.17 | |
GCP 100 bar | 0 | 17.26 | 9.63 | 16.21 | 0.46 |
5 | 21.76 | 17.2 | 20.06 | 0.32 | |
10 | 22.73 | 13.9 | 21.88 | 0.88 | |
20 | 24.70 | 11.91 | 23.83 | 2.17 | |
GCP 150 bar | 0 | 17.26 | 21.3 | 14.99 | 0.78 |
5 | 19.37 | 20.77 | 17.19 | 0.19 | |
10 | 21.86 | 20.16 | 20.01 | 0.62 | |
20 | 27.50 | 15.79 | 22.28 | 0.33 |
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Ren, J.; Lin, L.; Jiang, J.; Li, Q.; Hwang, S.-S. Effect of Gas Counter Pressure on the Surface Roughness, Morphology, and Tensile Strength between Microcellular and Conventional Injection-Molded PP Parts. Polymers 2022, 14, 1078. https://doi.org/10.3390/polym14061078
Ren J, Lin L, Jiang J, Li Q, Hwang S-S. Effect of Gas Counter Pressure on the Surface Roughness, Morphology, and Tensile Strength between Microcellular and Conventional Injection-Molded PP Parts. Polymers. 2022; 14(6):1078. https://doi.org/10.3390/polym14061078
Chicago/Turabian StyleRen, Jianping, Long Lin, Jing Jiang, Qian Li, and Shyh-Shin Hwang. 2022. "Effect of Gas Counter Pressure on the Surface Roughness, Morphology, and Tensile Strength between Microcellular and Conventional Injection-Molded PP Parts" Polymers 14, no. 6: 1078. https://doi.org/10.3390/polym14061078