Hydrophobic Oligomers
Poly(ether ether ketone) (PEEK) oligomer was analyzed with chloroform eluent using GPC K-802 (a column for organic SEC (GPC)). Although PEEK polymer cannot be dissolved in chloroform easily, PEEK oligomer can.
Sample : PEEK, Poly(ether ether ketone)
Columns : Shodex GPC K-802 (8.0mmID*300mm) x 2 Eluent : CHCl3 Flow rate : 1.0mL/min Detector : UV(254nm) Column temp. : Room temp.
PET oligomer was analyzed using GPC K-803 + K-802 (columns for organic SEC (GPC)). Poly(ethylene terephthalate) (PET) cannot be dissolved in ordinary solvents because there are many hydrogen bonds between the molecules. It can, however, be dissolved in a chloroform and a dichloroacetic acid mixture. Therefore, a chloroform / dichloroacetic acid (95/5) eluent is used for performing this analysis. A 5mM CF3COONa/HFIP eluent used for the analysis of PET polymer can also be used for the analysis of PET oligomer.
Sample : PET, Poly(ethylene terephthalate)
Columns : Shodex GPC K-803 + K-802 (8.0mmID*300mm each) Eluent : CHCl3/Cl2CHCOOH=95/5 Flow rate : 1.0mL/min Detector : UV(290nm), Shodex RI Column temp. : Room temp.
This figure shows the analysis results for epoxy resin oligomer with THF eluent using GPC KF-802.5 and KF-803 (columns for organic SEC (GPC)). Usually, two to four columns connected in series are used for GPC analysis. In this case eight columns were used to obtain high resolution.
Sample : Epon 1001
Columns : Shodex GPC KF-803 x 4 + KF-802.5 x 4 (8.0mmID*300mm each) Eluent : THF Flow rate : 1mL/min Detector : UV(254nm) Column temp. : Room temp
Polystyrene standard (Mw: 500) was analyzed using GPC KF-802 (a column for organic SEC (GPC)). For improving resolution, the appropriate flow rate should be selected considering the diffusion speed. In this case, a higher resolution can be realized with a lower flow rate. Although a reduction of the flow rate from 2.0mL/min to 1.0mL/min brought about a large difference in resolution, a reduction from 1.0mL/min to 0.5mL/min did not. Considering the time for analysis, the use of 1.0mL/min is recommended for the analysis of the sample.
Sample : PS, Polystyrene 500
Column : Shodex GPC KF-802 (8.0mmID*300mm)
Eluent : THF
Flow rate : (A)2.0mL/min
(B)1.0mL/min
(C)0.5mL/min
Detector : UV(254nm)
Column temp. : Room temp.
Polystyrene standrads, n-propylbenzene and benzene were analyzed using GPC KF-801 (a column for organic SEC (GPC)). Increasing the number of columns connected is an effective way of improving the resolution. In this case, the use of four columns improves the separation of polystyrene oligomer significantly.
Sample :
1. PS, Polystyrene (MW: 6,200)
2. PS, Polystyrene (MW: 300)
3. n-Propylbenzene
4. Benzene
Columns : Shodex GPC KF-801 (8.0mmID*300mm) Eluent : THF Flow rate : 1.0mL/min Detector : UV(254nm) Column temp. : Room temp.