Preparative SEC column packed with microporous particles prepared from cellulose

Abstract

New microporous particles with large pore size (mean pore diameter of 820 nm) are successfully prepared from a mixture of cellulose and konjac glucomannan (RC-KCM3) in 1.5M NaOH-0.65M thiourea aqueous solution by coagulating with 5 weight percentage (wt%) CaCl2, and then 2 wt% HCl aqueous solution. A preparative size-exclusion Chromatographic (SEC) column packed with the gel particles is used for the fractionation of a dextran in water. The exclusion limit and fractionation range of the stationary phase are molecular masses of 125 × 104 g/mol and 5.6 × 104 to 125 × 10 4 g/mol, respectively. The dextran [dextran 50, weight-average molecular mass (Mw) = 40.1 × 104 g/mol, polydispersity index (d) = 3.5] is fractionated by the preparative SEC column to obtain six fractions, and four of them are refractionated twice by the same preparative SEC column. The refractionated samples F-3-3 and F-4-3 are characterized by analytical SEC combined with laser light scattering and light scattering to obtain Mw of 91.8 and 61.9 × 104 g/mol, as well as d of 1.3 and 1.4, respectively. The results indicate that the fractions having narrow molecular mass distribution are satisfactorily prepared with the SEC column. The described SEC column can be successfully used to fractionate polymers in aqueous solution.