The molecular sieve powder is homogeneously dispersed in the polymer, and the particle size is usually in the order of microns. The hybrid film has a certain degree of uneven distribution due to the deposition. The polyimide-molecular sieve hybrid system has a unique three-phase structure: polymer, molecular sieve and cavity. Molecular sieve and polyimide connection between the small, often at the junction of the gap, the individual molecular sieve can play the role of bridging polymer. The semi-interpenetrating network or chemical bond exists between the silane-treated molecular sieve and the polyimide interface.