Molecular-shape selectivity tuned by donor-acceptor type copolymers as organic phase in reversed-phase high-performance liquid chromatography

摘要

The copolymer with a terminal reactive group (Copoly-VP(17)MA(12)) was newly designed and prepared by selecting 4-vinylpyridine (VP) as an electron-donating monomer and methyl acrylate (MA) as an electron-accepting monomer. Copoly-VP(17)MA(12) was grafted onto Porous silica particles by a silanol coupling reaction with the terminal group Individually. poly-VP15 and poly MA(20) With a terminal reactive group were also synthesized and co-grafted onto silica (Sil-cograft-VP(15)MA(20)) to compare the effect of the copolymer-grafted (Sil-Copoly-VP(17)MA(12)), and polymer co-grafted stationary phases in HPLC separation All the polymers were characterized by H-1 NMR and FT-IR analysis before grafting on silica Polymer grafting was confirmed by diffuse reflectance infrared Fourier transform (DRIFT), elemental analysis and thermogravimetric analysis (TGA) The intra- and intermolecular interaction between monomer units in copolymer-grafted and polymer co-grafted systems, respectively was observed by DRIFT measurement The detailed chromatographic study revealed using PAHs as solutes that remarkably higher selectivity for planaron-planar discrimination was observed with the copolymer-grafted phase than with the co-grafted stationary phase In this paper, it is also discussed that the selectivity enhancement by copolymer-grafting in the Sil-Copoly-VP(17)MA(12) phase can be brought through intramolecular interaction between VP and MA .