Successive Organic Solvent Fractionation and Characterization of Heterogeneous Lignin Extracted by p-Toluenesulfonic Acid from Hybrid Poplar

A successive organic solvent fractionation was reported in this work to obtain lignin fractions with narrow molecular weight distribution and high purity from p-toluenesulfonic acid-extracted lignin. A decrease was found in PDI of fractionated lignin compared with parent substrate from 3.31 to 1.44 and the amount of carbohydrate derivates was detected to decline implying an increase of purity. Calculated from the results of DTG, thermal...