There are two kinds of the polyimide according to the synthesis method, they are condensation polymerization type and addition polymerization type.

1. Condensation type polyimide: Condensation type polyimide has been seldom used as the matrix resin of composite materials, mainly used for manufacturing Polyimide film and coatings.

2. Addition polyimide: the widely used addition polyimide mainly includes polybismaleimide and norbornane Alkenyl terminated polyimide.