Difficulties associated with the preparation of polyimide-clay nanocomposites

2 Difficulties associated with the preparation of polyimide-clay nanocomposites 

The preparation of polyimide-montmorillonite nanocomposites presents challenges that are unique compared with the constraints associated with the polymers discussed above. Polyimides are utilized in the aerospace industry because of their balance of mechanical properties and high thermal stability. Polyimides have found value in the electronic packaging and insulation industrial because of the additional quality of electrical insulation. 

The commercial focus in these market areas is on aromatic polyimides. These are prepared in two steps  

The high temperature of the second step precludes the utilization of montmorillonite exchanged with the quaternary ammonium ions described in the work above. These quats are not stable at these temperatures. 

A series of articles by Delozier et al. [27-30] definitively demonstrates the inappropriate choice of quats utilized in the studies above, owing to their thermal instability at the temperatures employed in the second step of the polyimide synthesis. Organic modification of montmorillonite was explored to provide greater thermal stability and to be commensurate with the chemistry associated with the polyimide synthesis. 

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