Chemistry Reference
In-Depth Information
Earlier, however, it was speculated that guanidyl urea forms [
140
].
The curing mechanism of epoxy resins with imidazole was investigated. The following mecha-
nism was proposed [
137
]:
O
O
NN
H
+
H
NN
H
NN
C
2
H
5
C
2
H
5
C
2
H
5
O
OH
H
NN
NN
C
2
H
5
C
2
H
5
OH
or
NN
O
C
2
H
5
O
OH
NN
C
2
H
5
Many cyclic acid anhydrides are used industrially for cross-linking epoxy resins. These are mono
and polyanhydrides. Following are some typical commercially used anhydrides:
O
O
O
O
O
O
O
O
O
O
O
O
pyromellitic
dianhydride
phthalic
anhydride
maleic
anhydride
Cl
O
O
Cl
O
O
Cl
Cl
O
O
C
12
H
23
O
CH
3
O
dodecylsuccinic
anhydride
O
Cl
methylbicyclo [2,2,1]hept-5-
ene-2,3-dicarboxylic acid
anhydride
Cl
chlorendic
anhydride
O
O
O
O
R
O
O
photoadduct of alkylbenzene
and maleic anhydride
138
