Environmental Engineering Reference
In-Depth Information
O
H
3
C
O
O
O
H
3
C
OH
O
NH
2
H
2
C
OH
H
3
C
H
2
C
OH
H
3
C
Methacrylic acid
Acrylic acid
Acrylamide
2-Hydroxyethyl methacrylate
H
2
C
H
3
C
O
CH
2
H
2
C
O
N
2-Vinylpyridine
H
3
C
N
4-Vinylpyridine
Methyl methacrylate
FIGURE 20.2
Some frequently used monomers for the synthesis of IIPs.
H
3
C
CH
2
O
CH
3
O
O
H
2
C
H
2
C
O
CH
2
H
2
C
O
O
O
CH
3
H
3
C
O
CH
3
O
O
CH
3
Ethyleneglycol dimethacrylate
Trimethylolpropane trimethacrylate
FIGURE 20.3
Common cross-linkers in the synthesis of IIPs.
20.2.3.1.3 Solvents (Porogens)
One attribute of a good solvent for IIPs is that it should be able to dissolve all the com-
ponents of the polymerization mixture and at the same time participate in the physical
makeup synthesis of the IIP.
36
20.2.3.2 General Methods for Polymerization during IIP Synthesis
There are four polymerization methods used in the ion-imprinting technique: (i) bulk
polymerization
37
; (ii) suspension polymerization
38
; (iii) precipitation polymerization
39
; and
(iv) emulsion (surface) polymerization.
40
These four polymerization methods and the asso-
ciated imprinting procedure may as well be categorized into two groups termed as 2D
and 3D.
41
The 3D group takes place in three dimensions, implying that the cavities are
distributed in the “whole” surface of the polymer. Table 20.1 gives the summary of the
polymerization techniques.
