Abstract:

Advanced polymer chromatography (APC) is a newly developed high resolution polymer characterization technique. Within 10 min, it can separate polymers with high resolution and obtain the average relative molecular mass distribution parameters of the polymers. The M_r distribution of the depolymerized lignin product was well characterized with low relative standard deviation (RSD less than 1%) by APC system using ACQUITY AQ 450 Å, 200 Å, and 45 Å columns in series, with 10 μL injection volume, and weak alkaline phosphate buffer solution as the aqueous mobile phase at a flow rate of 0.5 mL/min. Compared with traditional gel permeation chromatography (GPC), the APC system had the advantages of high sensitivity and good reproducibility. The technique to determine the average relative molecular mass distribution of depolymerized lignin oligomers in aqueous phase described in this paper will pave the way for new methods to separate and analyze high performance natural materials, and the feasible method for the investigation of the mechanism of depolymerization and the regulation for liquefied lignin would also be established.

Key words: advanced polymer chromatography (APC), aqueous phase, average relative molecular mass, depolymerization, polydispersity index (PDI), sodium lignosulfonate