RECOMMENDATIONS FOR PROCESSING CELLULOSE ACETATE GRANULES - IG GRADE
BY INJECTION MOULDING
The conditions for injection
moulding IG Grade will vary depending on the type of injection moulding
machine used and the nature of the mould and article to be moulded. However
the general conditions below can be used as a starting point.
In processing cellulose acetate, the
following general care must be taken to get a reasonable quality moulded
part:
- The material should be Preheated / pre-dried properly before moulding,
otherwise bubbles, streaking, surface defects will appear in moulded
part
- The material should be free from contamination from other polymers
- The machine barrel should be cleaned thoroughly if it was being
used to mould another polymer
- The material should not be kept stagnant in the heated injection
barrel for an extended time
- The mould should be designed to have adequate venting
GENERAL MOULDING PARAMETERS
Pre-drying |
In tray oven for minimum of
1 ½ hours at 70C |
Injection temperature |
160 – 180 C |
Injection pressure |
10-50 kg/sq cm |
Mould temperature |
Preferably cooled by water,
or at room temperature |
|