Table 1.

List of lignin samples used in the flexible PU foam formulations and their measured properties.

No.	Process	Source	ID	Hydroxyl Content a (mmol/g)	Mn (Da)	Mw (Da)	PDI	Tg (°C)
1	Kraft	Softwood	1-K-SW	5.61	1990	6580	3.31	149
2	Organosolv	Hardwood	2-O-HW	4.56	1280	3440	2.69	104
3	Organosolv	Corn Stover	3-O-CS	3.90	1750	6240	3.57	143
4	Kraft	Softwood	4-K-SW	5.92	1770	6070	3.43	148
5	Organosolv	Peanut Shell	5-O-PS	3.48	1640	9080	5.54	96
6	Kraft	Softwood	6-K-SW	5.72	2030	8090	3.99	166
7	Kraft	Softwood	7-K-SW	5.37	1750	5510	3.15	155
8	Organosolv	Hardwood	8-O-HW	4.08	1640	4070	2.48	134
9	Kraft	Softwood	9-K-SW	6.70	2080	6920	3.33	152
10	Kraft	Bagasse	10-K-BA	4.63	2000	6550	3.28	147
11	Kraft	Softwood	11-K-SW	6.42	1540	4290	2.79	148
12	Kraft	Softwood	12-K-SW	5.22	2250	12100	5.38	158
13	Kraft	Softwood	13-K-SW	3.49	2175	7280	3.35	138
14	Organosolv	Hardwood	14-O-HW	5.19	1490	4250	2.85	84
15	Kraft	Hardwood	15-K-HW	6.79	1030	1740	1.69	134

^a: Hydroxyl content is based on the total OH content of lignin (Aliphatic OH + Ph-OH and –COOH).