IMID-AMID UND HARNSTOFF-SILOXAN-BLOECKE ENTHALTENDE THERMOSTABILE BLOCKCOPOLYMERE.

摘要

Novel thermally stable block copolymers containing (imide-amide) and (urea-siloxane) blocks.
More precisely, these copolymers are obtained by a chain sequence of the following two stages:
- stage (a): preparation of an oligomer containing end N=C=O groups from an aromatic diisocyanate and a monoanhydride of an aromatic tricarboxylic acid, and
- stage (b): reaction of the said oligomer with a diamine of formula:

in which: X denotes:

each of R1, R2, R3, R4 and R5 denotes a hydrocarbon radical, x is a number ranging from 2 to 8 and the sum y + z is between 0 and 100.
These copolymers are employed especially for the production of coating films.