26 Bifunctional Silicas with Immobilized Lignin
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Table 26.1 Lignin-containing sample description and acronyms
N 0 Sample name Description
Structure of silicas’ surface layer
1 LigA1
Lignin + SiO 2 (A-300)
Pristine silica
Si
O
Si
Si
O
OH
Si
OH
O
Si
O
O
H
H
O
H H
HO
2 LigA2
Lignin + SiO 2 –CH 3 (100%)
Methylated silica
Si
O
OH
Si Si
O
OH
Si
O
Si
OH
O
CH 3
H 3 C Si CH 3
O
CH 3
H 3 C
Si
CH 3
O
3 LigA3
Lignin + SiO 2 –CH 3 (30%)
4 LigA4
Lignin + SiO 2 –H (100%)
Hydride silica
H
H
Si
O
Si Si
O
Si
O
O O
Si
HO
O O
Si OC 2 H 5
5 LigA5
Lignin + SiO 2 –NH 2 (100%)
Aminated silica
Si
O
Si Si
O
OH
Si
O
O O
Si
CH 2
CH 2
CH 2
NH 3 +
O
–
HO
6 LigA6
Lignin + SiO 2 –CH 3 (30%)–NH 2 (30%) Combination of different groups
including OH
7 LigA7
Lignin + SiO 2 –CH 3 (30%)–H (30%)
8 LigA8
Lignin + SiO 2 –NH 2 (30%)–H (30%)
9 LigA9
Lignin + SiO 2 –H (30%)
Combination of silicon hydride
groups and OH
10 LigA10
Lignin + SiO 2 –NH 2 (30%)
Combination of amino groups and
OH
26.3 Results and Discussion
Ensuring interaction between the silica surface and the polymer is a main task
when creating organic/inorganic materials. In spite of the presence of different types
of functional groups, lignin is a low reactive polymer, and providing interaction
with the matter introduced has some difficulties. As was mentioned above, lignin