General Description
PA 66 is generally used in the automotive and engineering industry where the applications include food contact parts and screw machined electrical insulators. Often glass filled grades are used.
Some glass-fibre-filled polyamide 66s have been developed for operation in air at temperatures of up to 200-210 °C. These PA66’s provides much better performance than the heat-stabilized ones commonly in use.
Pre-Production
If the moisture content is more than 0.2 per cent, the flow properties of the melt are affected. If the material is very wet (e.g., has been exposed to air for more than 8 hours) vacuum or desiccant drying is necessary.
Temperature ºC
Zone No.
Location
From
To
–
Hopper Throat
75
90
1
Barrel Rear (hopper end)
275
300
2
Barrel Middle
270
290
3
Barrel Middle
270
295
4
Barrel Front
265
295
5
Barrel Nozzle
260
290
6
Mould
20
100
Temperature ºC
Zone No.
Location
From
To
–
Hopper Throat
75
90
1
Barrel Rear (hopper end)
280
300
2
Barrel Middle
285
305
3
Barrel Middle
290
305
4
Barrel Front
275
300
5
Barrel Nozzle
270
295
6
Mould
55
95
Processing Notes
Adjust speed to suit the moulding cycle but do not use a screw surface speed of greater than 0.5m/s. Because this type of material solidifies quickly, the mould must be filled in a short time.
Back pressure should be kept as low as possible At a temperature of 280ºC the maximum residence time in the barrel should not exceed 5 minutes. When the temperature is 320ºC then the maximum residence time in the barrel should not exceed 3 minutes.
Tool Requirements
- Shrinkage values can range from 1% to 2%. The addition of glass fibre will reduce the shrinkage to 0.2 to 1%.
- Runner diameters of between 3 to 6mm are common; diameters above 8mm tend to increase the cycle time rather than improve the flow of molten material through the feed system.
- To achieve a high surface gloss on the moulding, the finish of the cavities and cores must be excellent and fault free.
Post Production
Easily purged by a more viscous polymer – if in doubt purge with HDPE or PP, or strip and clean.
Portfolio:
Polyram – PA66 – Plustek
Radici – PA66 – Radilon A – Radiflam A – Heramid A
