Nanopore generation could be accomplished in thin films of fully alicyclic polyimides derived from an alicyclic dianhydride and diamines. A silylation method for the alicyclic diamines was used to synthesize high molecular weight alicyclic polyimides. Triblock copolyimides were prepared using N-silylated alicyclic diamines, alicyclic dianhydride, and a thermally labile polymer. Nanoporous films of fully alicyclic polyimides were prepared through heating of the copolyimide films to induce thermal degradation of the labile block.