410090-47-0Relevant articles and documents
Synthesis of wholly alicyclic polyimides from N-silylated alicyclic diamines and alicyclic dianhydrides
Watanabe, Yasufumi,Sakai, Yoshimasa,Shibasaki, Yuji,Ando, Shinji,Ueda, Mitsuru,Oishi, Yoshiyuki,Mori, Kunio
, p. 2277 - 2281 (2007/10/03)
A new synthetic method to give wholly alicyclic polyimides with high molecular weights has been developed. The polymerization of cyclobutanetetracarboxylic dianhydride (1a) or bicyclo [2.2.1]-heptane-2-methanecarboxylic-3,5,6-tricarboxylic-2,3:5,6-dianhydride (1b) with various N-silylated alicyclic diamines (2) was carried out in N,N-dimethylacetamide (DMAc) at room temperature, giving poly(amic acid trialkylsilylester)s (3) as precursor polymers that were hydrolyzed to poly(amic acid)s (4) with inherent viscosities up to 0.99 dL/g. Both polyimide precursors were readily converted to corresponding polyimides (5) by thermal treatment. These polyimides are readily soluble in polar aprotic solvents such as 1-methyl-2-pyrrolidone, N,N-dimethylacetamide and dimethyl sulfoxide at room temperature, and showed high thermal stability (Td10 = 420-445 °C in N2) and excellent transparency at wavelengths above 250 nm. The average refractive index of the polyimide 5aa was 1.498, and the dielectric constant estimated from the refractive index was 2.47.