EDGE Application Guide Page 1 of 1
How to Extract Polymer Samples using the EDGE 2021-01
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How to Extract Polymer Samples using the EDGE
Introduction
Polymers and plastics are a widely varied class of samples that are ubiquitous in modern life. Analytes of interest can be additives such
as antioxidants, flame-retardants, UV stabilizers, unreacted polymer or oligomers, or proprietary compounds. Please use this method to
extract your analyte(s) of interest from plastic samples.
Sample Types
Plastic pellets, plastic sheets, medical devices, polymer spin fibers
PET, LDPE, HDPE, LLDPE, Polypropylene, PVC, TPE
Sample Preparation
1. Reduce the individual particle size of the plastic sample by either milling, grinding, cutting, or some other form of
homogenization.
2. Assemble a Q-Cup with the S1 stack of Q-Discs (C9+G1+C9).
3. Weigh in the desired amount of sample. The recommended sample size is 2 g or less.
4. Place a Q-Screen on top of the Q-Cup and insert it using the Q-Screen tool.
EDGE Extraction
5. Prepare the EDGE by priming appropriate solvent. It is recommend to use a mix of a nonpolar solvent mixed with a polar protic
or polar aprotic solvent in a ratio of (1:1). It is recommended to use the solvent mixture that is currently being used.
Note: Solvents that fully dissolve the plastic sample should not be used, as they will lead to clogs in the lines. If there
is any uncertainty about a solvent, first test the solvent by submerging a small amount of sample in a beaker or
scintillation vial containing the solvent.
6. Program the EDGE method stated below with the appropriate solvent.
7. Extract the sample using the EDGE method below.
Post Extraction Work Up
8. Remove the extract vial from the rack.
Note: If the extract is cloudy, this likely indicates that the polymer had partially dissolved in the solvent at the
elevated temperature of the extraction and has crashed out of solution after cooling.
9. Dry down the extract to the desired volume using an evaporator.
10. Transfer extract to LC vial, and analyze using LC-MS or LC-UV.
Method Development Tips
• Because of the possibility of plastics melting and coming through the filter, it is best practice to start at a low temperature and
increase by 10◦C after a successful extraction.
• A physical change may occur in the sample after extraction. Common changes in the sample include: swelling, melting, and
increasing in transparency. If a change does occur, then the temperature of extraction should not be increased further.
• If a solvent mixture is solvating a sample too readily, try reducing the nonpolar portion of the mixture to instead have a higher
ratio of polar protic or polar aprotic solvent.
• If recovery is lower than expected with this method, consider increasing the hold time or adding additional cycles.
Cycle Solvent Top add
(mL)
Bottom add
(mL)
Rinse
(mL)
Temperature
(°C)
Hold
(mm:ss)
1 Extraction Solvent 20 0 0 70 10:00
Wash Extraction Solvent 15 - - 70 00:15