Spherical Polyimide Particles as a Novel Stationary Phase in Liquid Chromatography

Abstract

Spherical polyimide (PI) particles have been introduced as a stationary phase in liquid chromatography (LC). The PI was prepared with the starting materials of pyromellitic dianhydride (PMDA) and 4,4'-diaminodiphenyl ether (4,4'-oxydianiline, ODA), resulting the spherical PI (PMDA-ODA type) particles with an average diameter of about 5 μm. The synthesized PI particles were packed into a conventional blank LC column having a typical size of 4.6 mm i.d, 150 mm length, and the retention behavior for a group of polycyclic aromatic compounds (PACs) was evaluated in LC. The retention behavior was compared with that obtained on a commercially-available octadecylsilica (ODS) phase. The results indicated a significantly larger retentivity of PACs on the PI stationary phase than that on typical ODS stationary phases, where the retention tendency on the PI phase for various PACs having different molecular size and shape was similar to the trend on the ODS phase. The large retention on the PI phase can be interpreted on the basis of the surface structure of the PI particles, because a number of aromatic functionalities are in the chemical structure of the polymer chain backbone.

Retention Behavior of Various Aromatic Compounds on Poly(butylene terephthalate) Stationary Phase in Liquid Chromatography

“…Taking advantage of a good stability to a mobile phase of highly-acidic and highly-basic conditions, various applications have been reported [40]. Another advantageous feature of the polymer-based phase in separation science is a simple phase structure design and the relatively easy synthesis of the phase, allowing a cost-effective development of novel stationary phases [41]. Recently, various types of polymeric fibers have been reported as a novel stationary phase.…”

Fibrous Polyimide Stationary Phase for the Separation of Aromatic Compounds in Reversed-Phase Liquid Chromatography

“…In conventional silicagel-based stationary phases such as a typical ODS phase, functional groups (such as the ligands for the separation) bond with silanol groups on the surface of silicagel particles. However, the introduction of synthetic polymer materials as a support for the stationary phase can counter the several disadvantages of silicagel support [32]. One of the advantages of the polymer-based stationary phase is the easy synthesis of the particle as the support of stationary phase, and in addition, the designs of the chemical structure of the ligands are very flexible [33,34].…”

Molecular Shape Selectivity for Polycyclic Aromatic Compounds on a Poly(benzoguanamine-<i>co</i>-melamine-<i>co</i>-formaldehyde) Stationary Phase in Reversed-Phase Liquid Chromatography

“…However, typical ODS phases still have some problems to be solved, such as insufficient heat resistance and chemical resistance, along with a limitation on the mobile phase composition. Polymer-based stationary phases having a good heat resistance and also a good chemical resistance have been applied as a stationary phase in LC [16][17][18]. Polymer-based materials is already employed in some chromatographic methods, especially for the stationary phase in LC and also in size-exclusion chromatography (SEC) as one of the variations in LC separation methods [19][20][21], as well as in gas chromatography (GC) [22,23].…”

“…Recently, our research group introduced novel polymer-based stationary phases, such as a poly(benzoguanamine-co-formaldehyde) (BF) as separation media in LC [17,18]. The BF stationary phase showed a unique molecular shape selectivity for the separation of aromatic compounds.…”