Synthesis of wholly alicyclic polyimides from N-silylated alicyclic diamines

Abstract

A synthetic method to give wholly aliphatic polyimides with high molecular weights has been developed. The polymerization of cyclobutanetetracarboxylic dianhydride (CBDA) with 5-trimethylsilylamino-N-trimethylsilyl-1,3,3-trimethylcyclohexanemethylamine (NSD-1) or 2,5(2,6)-bis(N-trimethylsilylaminomethyl)bicyclo[2.2.1]heptane (NSD-2) was carried out in polar aprotic solvents at room temperature, giving poly(amic acid trimethylsilyl ester)s (PATSEs) as precursor polymers which were hydrolyzed to poly(amic acid)s (PAAs) with inherent viscosities up to 0.74 dL g-1. Both polyimide precursors were readily converted to the corresponding polyimides by thermal treatment.