塑料的收缩率一般是指塑料制品冷却固化经脱模成型后,其尺寸与原模具尺寸间之误差百分比,可依ASTM D955方法测得。 在塑料模具设计时,须先考虑收缩率,以免造成成品尺寸的误差,导致成品不良。以下列举几项常用塑料原料之收 缩率比较。现总结常用塑料的收缩率如下:
塑料品种 | 原料收缩率 | 改性料类别 | 改性料收缩率 |
ABS | 0.4-0.7 |
ABS+20%GF |
0.2-0.4 |
|
|
ABS+FR |
0.4-0.7 |
|
|
ABS+20%GF+20%FR |
0.1-0.3 |
PC/ABS |
|
35%PC |
0.4-0.6 |
|
|
PC/ABS+20%GF |
0.2-0.4 |
|
|
PC/ABS+FR(Br) |
0.3-0.6 |
AS | 0.4-0.6 |
|
|
HIPS | 0.5-0.6 |
|
|
PS | 0.3-0.6 |
|
|
SAN | 0.5-0.6 |
|
|
LDPE | 1.5-5.0 |
|
|
HDPE | 1.5-3.0 |
|
|
PP | 1.0-2.5 |
PP+20%talc |
1.0-1.5 |
|
|
PP+20%GF |
0.5-0.8 |
|
|
PP+FR(溴系) |
1.5-1.8 |
|
|
PP+20%GF+FR |
0.3-0.5 |
PC | 0.8 |
PC+20%GF |
0.3-0.5 |
|
|
PC+20%GF+FR(无卤) |
0.2-0.4 |
PET | 1.2-2.0 |
|
|
PBT | 1.5-2.5 |
|
|
PA6 | 0.5-2.2 |
PA6+30%GF |
0.3-0.5 |
|
|
PA6+30%GF+FR(无卤) |
0.2-0.4 |
|
|
PA6+30%填充 |
0.6-0.9 |
PA66 | 0.5-2.5 |
PA66+30%GF |
0.4-0.7 |
|
|
PA66+30%GF+FR |
0.2-0.4 |
|
|
PA66+FR(无卤) |
0.8-1.2 |
PPS | 0.2 |
|
|
PPO | 0.5-0.7 |
|
|
PF | 1.2 |
|
|
EP | 0.2 |
|
|
PTFE | 3.5-6.0 |
|
|
POM | 1.9-2.3 |
|
|
PMMA | 0.1-0.8 |
|
|
PVC-rigid | 0.5 |
|
|