4. Content of Carbonyl Groups (mmol/g) Estimated via Semimicro Scale PAR on Loblolly Southern Pine Dioxane Lignin, White Oak Dioxane Lignin, and White Oak Enzymatically Mild Acidolysis Lignin.

	carbonyl content (mmol/g)
Loblolly Southern Pine dioxane lignin	0.94 ± 0.01
White Oak dioxane lignin	1.07 ± 0.03
White Oak enzymatically mild acidolysis lignin	0.77 ± 0.01