Selective chromatographic separation of polycarbonate according to hydroxyl end-groups using a porous graphitic carbon column.
Porous graphitic carbon (PGC) has shown unique separation efficiency in liquid chromatography for a wide range of substance classes. In the characterization of polymers PGC has particularly been used for analysis of polyolefins. Its retention mechanisms differ dramatically from those of silica-based stationary phases and therefore allow interesting applications. Due to its unprecedented retention mechanisms PGC does not only promise good separation performance for polyolefins but also for more polar polymers such as Polycarbonate (PC). In this study, we determined the critical conditions of PC on PGC using CHCl3/dichlorobenzene (DCB) and CHCl3/trichlorobenzene (TCB) as eluents achieving separations according to hydroxyl end-groups, which was confirmed by MALDI-TOF-MS analysis. As the content of TCB at the critical point was lower compared to that of DCB, it was concluded that TCB is a stronger desorption promoting eluent than DCB for the present system. The temperature influence on the critical point was then investigated revealing that with increasing temperature the content of desorption promoting eluent has to be raised in order to achieve critical conditions. Furthermore, a peak shifting over time was observed using TCB as desorption promoting eluent, which was attributed to irreversibly adsorbed PC on the column material. However, when a flow cell-IR detector was applied monitoring the eluted samples, a recovery rate close to 100% was found.
Fraunhofer Institute for Structural Durability and System Reliability (LBF), Division Plastics, Group Material Analytics, Schlossgarten Str. 6, 64289 Darmstadt, Germany.
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Apel
SABIC, Analytical Technology, Plasticslaan 1, 4612 PX Bergen op Zoom, The Netherlands.
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Uliyanchenko
SABIC,1600 Industrial Blvd., Sugar Land, TX 77478, USA.
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Moyses
SABIC, Analytical Technology, Plasticslaan 1, 4612 PX Bergen op Zoom, The Netherlands.
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Rommens
SABIC, Analytical Technology, Plasticslaan 1, 4612 PX Bergen op Zoom, The Netherlands.
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Wold
Fraunhofer Institute for Structural Durability and System Reliability (LBF), Division Plastics, Group Material Analytics, Schlossgarten Str. 6, 64289 Darmstadt, Germany.
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Macko
Fraunhofer Institute for Structural Durability and System Reliability (LBF), Division Plastics, Group Material Analytics, Schlossgarten Str. 6, 64289 Darmstadt, Germany.
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Rode
Fraunhofer Institute for Structural Durability and System Reliability (LBF), Division Plastics, Group Material Analytics, Schlossgarten Str. 6, 64289 Darmstadt, Germany. Electronic address: robert.bruell@lbf.fraunhofer.de.
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Brüll
D002853:Chromatography, Liquid / Q000379:methods*; D006108:Graphite / Q000737:chemistry*; D006900:Hydroxylation; D008970:Molecular Weight; D011076:Polycarboxylate Cement / Q000302:isolation & purification*; D016062:Porosity; D012015:Reference Standards; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013055:Spectrophotometry, Infrared; D013696:Temperature; D013997:Time Factors
D011076:Polycarboxylate Cement; C005506:polycarbonate; D006108:Graphite
Liquid chromatography at critical conditions; Poly(bisphenol A)carbonate; Porous graphitic carbon