| aqueous antioxidant |
high aromatic OH content |
B5 |
| |
oxygen-rich (ketone or -OH)
side-chain |
|
| |
low CH3/CH2 content in side-chain |
|
| nonaqueous antioxidant |
high aromatic OH content |
B6 |
| |
oxygen-poor (ketone or -OH)
side-chain |
|
| |
high CH3/CH2 content in side-chain |
|
| adsorbent in the aqueous
environment (biochar) |
high porosity and surface
area (high content of potential volatiles in original lignin; intact,
noncondensed propanoid side-chain and residual sugars) |
B6 |
| |
high oxygen (high S/G) and hydroxyl content (depolymerization) |
|
| |
low degree of carbonization |
|
| |
low molecular weight |
|
| filler
in hydrophobic composite/rubber
(biochar) |
low oxygen
content |
B5 |
| |
compatible for filler–matrix interaction (electronic interactions
between aromatic rings due to graphitization or increased sp2/sp3) |
|
| |
compatible for filler–filler interaction (electronic interactions
between aromatic rings due to graphitization or increased sp2/sp3) |
|
| component in lubricant |
high PDI or sufficient interaction
between lubricant components (sufficient hydrogen bond formation) |
B1 |
| carbon fiber (high
conductivity
application such as electrodes or supercapacitors) |
high degree of graphitization
(high sp2/sp3) |
B4 |
| |
high porosity and surface
area (high content of potential volatiles in original lignin; intact,
noncondensed propanoid side-chain and/or residual sugars) |
|
| |
low content of oxygen (removed
during pyrolysis) |
|
| carbon
fiber (mechanical) |
low/intermediate molecular
weight with sufficient thermal mobility to ensure generation of a
crystalline structure after fiber formation |
B6 |
| |
broader PDI to facilitate
a more irregular graphitic structure with greater fiber diameter and
surface area |
|
| free phenolics/bio-oil |
high content of β-O-4′ linkages or
at least low content of condensed structures |
B3 |
| compact lignin nanoparticles |
presence of high-molecular-weight
lignins acting as nucleation sites primarily aggregating through hydrophobic
interactions |
B5 |
| hollow lignin nanoparticles |
presence of amphiphilic
low-molecular-weight lignins acting as stabilizers at the interphase
between aqueous-organic solvents not mixing ideally |
B7 |
