TA Instruments Q2000 DSC:
Differential Scanning Calorimetry measures the heat flow of a sample at a given temperature. This allows for analysis of thermal properties as well as phase transition/composition testing. The Q2000 with the Liquid Nitrogen Cooling System (LNCS) allows for samples to be analyzed from -180oC to 550oC; the autosampler allows for samples to be queued up and run automatically.
Important Reminders:
An accurate analysis requires a reference pan of the same material and size being used. The reference and sample pans weight should have no more than a 500µg difference.
The LNCS autofills from a 230 liter LN2 dewar. A full 230 liter dewar will last for 24-48 hrs of continuous running depending on run conditions. If you need help moving the dewar into place please see Brenda or Dave Jung. The dewars are very heavy, please ask for help if needed!!!
Sample handling:
For best results the entire bottom of the sample pan should be covered, this usually requires between 5-10 mg of sample- depending on sample density.
Weigh and record weights of the sample pan and reference pans, including lids. There are two types of lids, Hermetic and regular. Hermetic lids should be used when no loss of vapor is desired. The two lid types are color-coded: Blue for Hermetic, black for regular, make note of the color-code.
Place sample into pan, so that it covers the bottom of the pan. Place the lid on the pan and use the corresponding color-coded die to seal the lid to the pan. You need to put very little effort into using the crimper. If it is hard to close, stop and realign the pan. Also make sure that only one lid is on the sample pan. Once the sample pan is sealed, reweigh the pan. The difference in weight is the sample weight, record this as well. Load the sample pan into one of the 50 autosampler spots and note the position. Crimp the empty reference pan and load it into one of the 5 references spots and note the position.
Software Interface:
There are two software systems used by the DSC, TA Advantage for data acquisition and Universal Analysis for data analysis.
To start TA Advantage software, first start the TA instrument Explorer software, allow for the instrument to connect to the explorer. Once that is done, you’ll see a yellow Ethernet icon on the instrument icon, double click the instrument icon and it will launch the acquisition software.
Create a new sequence by pressing the blank sheet of paper icon on the left most panel. In the center panel, first tab- Summary, choose test type, record sample name, sample size, pan type and position as well as data pathway and file name. In the second tab-Procedure, make sure test type is correct and use the editor to define run parameters. The last tab-notes, allows you to input sample purge gas and flow rate. The current set up for the DSC (03/2012) is Gas 1: Helium or Analytical Gas, Gas 2: Nitrogen.
To add runs to your queue, press the icon with a highlighted row with a plus button in the left most panel. The software auto increments the file name and pan position, but you can adjust these as necessary. When you have queued up all your samples and set your parameters, double click first run in the left most panel to start the run. You can also highlight the run you want to start with and click the green triangle located under the File menu.