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13.0 FINISHED PRODUCT
13.1 TESTING PRINCIPLE
The finished product must first be broken into chips which are ground to a powder using the polymer
grinder then dried using the drier and vacuum pump, all of which are optional extras.
Note that a quantity of liquid nitrogen is required to assist with the grinding process, so suitable
storage and handling procedures are required.
When the polymer is dry, it MUST be transferred to the PET Plus barrel using a procedure that en-
sures that the polymer does not come into contact with any external air.
13.2 INDUSTRIAL GRINDER
High speed grinding and chipping machinery is used to pulverise samples.
The equipment must be used in accordance with the manufacturers instruction manual and ear
protection must be used at all times in the vicinity of the grinding equipment.
Note that liquid nitrogen is used to pre-cool samples.
WARNING: ALWAYS WEAR SAFETY GLASSES AND HEAT RESISTANT GLOVES
WHEN HANDLING LIQUID NITROGEN WHICH IS AT -196ºC
AMETEK recommends the Fritsch Pulverisette 15, which is capable of reducing a pre-form to chip in
seconds. It may be floor or bench mounted and comes complete with an 8mm sieve.
NoTE: A coarse sieve (8mm) is used
to produce chip and very little powder,
thus making cleaning easy. A sieve to
produce powder could be used but this
would necessitate stripping the system
for cleaning after pulverising each
sample. Therefore, it is better to chip
the sample in the pulveriser and then
to grind to powder using the Polymer
Grinder.
PET Plus User Manual
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