ABSTRACT
This chapter discusses the polyimide synthesis, processing, properties, and applications. Polyimides are among the most temperature-resistant engineering plastics currently available. Due to the intractability of fully cured polyimide resins, they are sometimes supplied as precursor solutions of the polyamic acid. The fully cured polyimide is produced by applying heat to remove the solvent and initiate the polycondensation reaction forming the fully cured polyimide. Skybond resins are based on 3,3',4,4'-benzophenone tetracarboxylic dianhydride (BTDA). The polyimide precursor solutions are prepared by reacting BTDA with a variety of materials, including alkyl alcohols and aromatic diamines. Polymerization of monomer reactants undergoes an addition-type reaction. The reaction sequenceinvolves 4,4'-methylenedianiline and 5-norbornene-2,3-dicarboxylic acid monomethyl ester and 3,3', 4,4'-benzophenone tetracarboxylic acid dimethyl ester which produces methanol, water, and the following intermediate. The reaction sequence used to produce this aromatic thermoplastic polyimide is different from most other sequences because aromatic isocyanates are used as starting materials.
