While Mw (5A) is initially highest for lignin without additives at 7.8-10 3 g/mol, as the reaction time progresses the ML, SPC and SPC/NaOH test series approach a mean value of ~5.9-10 3 g/mol. This corresponds to a reduction of about 25% after 60 minutes. It is particularly interesting that the largest reduction of Mw of all test series, except for the raw lignin, takes place in the range of the first 5 minutes.