Today we talk about the three main injection molding temperatures and their settings.
3. Drying temperature in the injection molding temperature
Some materials have trace amounts of water molecules, which will promote the accelerated decomposition of polymers, such as PC, PBT, etc., so they must be fully dried before molding.
If the drying is not in place, not only will the decomposition of the material be accelerated, and a large number of bubbles will be generated, and the fluidity will also become very good and easy to produce defects such as drape. Therefore, it must be dried well before molding.
See the table below for specific settings for reference;
Commonly used plastic injection processing information
Material name | Density | Mold temperature | Material temperature | Decomposition temperature | Drying temperature | Shrinkage rate |
GPPS | 1.04-1.09 | 30-70 | 170-260 | 280 | 80 | 0.2-0.8 |
HIPS | 1.08-1.10 | 40-60 | 190-290 | 310 | 80 | 0.2-0.8 |
ABS | 1.05 | 40-90 | 200-240 | 280 | 75-80 | 0.4-0.7 |
LDPE | 0.91-0.94 | 30-60 | 150-230 | 300 | 70-85 | 1.5-4.0 |
HDPE | 0.94-0.97 | 30-80 | 160-280 | 300 | 70-85 | 1.5-3.6 |
PP | 0.9-0.91 | 30-90 | 190-290 | 320 | 70-90 | 1.0-2.5 |
Soft PVC | 1.16-1.35 | 20-40 | 140-190 | 200 | 70 | 1.0-2.5 |
Hard PVC | 1.35-1.45 | 30-60 | 140-190 | 200 | 80 | 0.1-0.6 |
PA-6 | 1.15 | 20-90 | 210-300 | 320 | 80-100 | 0.8-1.5 |
PA-66 | 1.15 | 20-90 | 230-310 | 360 | 85-120 | 1.2-1.8 |
PMMA | 1.18 | 40-100 | 220-250 | 260 | 80-100 | 0.1-0.8 |
PC | 1.20 | 80-110 | 250-320 | 360 | 110-130 | 0.4-0.8 |
POM | 1.41-1.43 | 60-100 | 160-210 | 230 | 60-80 | 1.8-3.5 |
PET | 1.2-1.38 | 50-120 | 250-310 | 360 | 140-180 | 0.2-2.0 |
PBT | 1.31 | 50-80 | 220-270 | 280 | 120-140 | 0.9-1.8 |
PBT Fiber | 1.52 | 60-90 | 230-280 | 290 | 120-150 | 0.4 |
PPO | 1.06-1.07 | 80-150 | 280-340 | 360 | 110-140 | 0.1-0.7 |
PPS | 1.36 | 120-180 | 280-340 | 390 | 130-150 | 0.5-0.7 |
LCP | 1.4-1.7 | 30-150 | 300-400 | 420 | 120-150 | 0.1-0.6 |