Table 1.

Surface free energies of LCNFs with different lignin contents.

Test Liquids	${\gamma }_L$	${\gamma }_L^p$	${\gamma }_L^d$
Water	72.8	51.0	21.8
Formamide	58.2	18.7	39.5
Ethylene glycol	48.3	19	29.3
Solid Samples	${\gamma }_S$	${\gamma }_S^p$	${\gamma }_S^d$
CNFs	53.6	4	49.6
5-LCNFs	51.7	8.5	43.2
9-LCNFs	50.5	7.8	42.7
14-LCNFs	47.6	3.5	44.1