PerkinElmer TGA 8000, Installation And Hardware Manual

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Overview . 21
8. The removable quartz furnace chamber sleeve regulates furnace convection by
reducing the effective furnace volume. The reduced volume also enhances gas
switching time because there is less furnace volume to displace.
9. The antistatic device creates an ion stream which is an invisible curtain of charged
particles that surrounds the sample loading area. This minimizes static cling between
the sample pan and the furnace wall during sample loading and static drift during
analysis. Loading fine, powdered, or static-sensitive samples is no longer a problem.
The device can be controlled from the control panel in the software.
In addition to these features, there is an autosampler designed for both the R&D laboratory
and the quality control/quality assurance environment. The autosampler increases the speed
of analysis by being able to hold up to 48 samples ready for analysis. The autosampler
enables samples to be prepared and run during the same shift. Using the Pyris Player feature
of Pyris Software, you can create play lists that will run the samples in the autosampler tray
and analyze the data automatically.
The following sections describe requirements for your Thermal Analysis System. Make sure
your laboratory meets all of the requirements before you try to install the system. You should
step through the topics in the order presented below. You can get from one topic to the next
by either returning to this topic or by clicking on a "continue" hotspot at the end of the topic.
Operating Variables in the TGA 8000
In thermogravimetric analysis, the object of an experiment is to record the change in weight
of a sample as function of temperature or time using a constant heating rate or a more
complex temperature program. Below are some techniques that can be used to obtain the
most accurate data in a minimum amount of time with a TGA 8000.
Sample Preparation
The TGA 8000 can analyze solid or liquid samples. Solid samples can be in the form of film,
crystal, or grains. In some cases, you may want to chop or grind the sample to create a large
surface area that is exposed to the purge gas atmosphere. In other cases, larger chunks or
sections of sample may be placed directly into the sample pan or crucible for analysis.
Sample Size
The size of sample that can be analyzed ranges from <1 mg to 400 – 500 mg. In most cases,
the typical sample size for TGA analysis is 2 – 50 mg. The type of transition or reaction that
you expect to occur in the sample should dictate the amount of sample used. For example, in
the case of polymer decomposition studies, sample sizes of 2 – 15 mg are recommended
since very large weight loss values are associated with this type of experiment. If there will
be a very small weight loss such as with water loss or solvent evaporation, larger sample
sizes should be used. It is not uncommon to use samples as large as 40 – 50 mg.
Temperature Range
The temperature used for your experiment will depend on the type of samples to be run as
well as the specific application performed. The standard furnace operates from subambient
to 1200°C with a temperature precision of ± 2°C. This furnace has broad applications in the
polymer, pharmaceutical, and organic chemical industries.
Because of the unique design of the TGA 8000, you can perform controlled heating or cooling
experiments as well as constant temperature experiments as a function of time. You can
even perform multiple-step experiments using any combination of heating, cooling, or
isothermal segments, thereby allowing the performance of virtually any thermogravimetric