Chemistry Reference
In-Depth Information
meta
-phenylene diamine, methylene dianiline, and oxy-dianiline. A typical polyimide preparation
can be shown as follows:
O
O
n
O
O
+
n
H
2
N
O
O
O
2
H
O
O
N
H
N
n
O
HO
OH
O
O
polyamic acid
O
O
N
N
O
n
O
O
The above shown polymer melts above 600
C and is heat stable up to 500
C in an inert
atmosphere. It is sold under the trade name of Kapton. A different polyether-imide sells under the
trade name of Ultem.
Another route to polyimides is through reactions of diisocyanates with dianhydrides [
89
,
90
]:
O
O
n
O
O
O
N
+
n
O
O
NO
O
O
N
O
O
O
O
N
n
O
O
O
O
N
N
n
O
O
The reaction is kept between 120 and 200
C[
91
]. In place of isocyanates, it is also possible to use
aldimines or ketimines, as well as silylated diamines.
