Page 302 - Engineering Plastics Handbook

H O O
O C N CH 2 N OH + R N C O

HO
O

H O O
O C N CH 2 N OH

N O
R
H O O

O O
H OH
+ O C N CH N
N OH 2
R
O O
Figure 12.7 Cyclization of imide ring.

O
O C N CH 2 NH OH O C N CH 2 NH 2 + CO 2

Figure 12.8 Carbamic acid decomposes to amine and carbon dioxide.

O
O C N CH N C O + H O O C N CH NH
2 2 2 OH

O C N CH 2 NH + CO 2
2
Figure 12.9 Isocyanate ends up as amine in presence of water.

O
O
O C N CH N C O + HO
2
O O
O
O
C O
O C N CH N O
2
H O O
Figure 12.10 Monoacid reacts with isocyanate to form
mixed anhydride.

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