Colorless Polyimides Derived from Octahydro-2,3,6,7-anthracenetetracarboxylic Dianhydride

A cycloaliphatic tetracarboxylic dianhydride, octahydro-2,3,6,7-anthracenetetracarboxylic dianhydride (OHADA) was synthesized to obtain novel colorless polyimides (PIs). Herein, approaches for decolorizing an OHADA prototype and simplifying the entire process are described, a plausible steric structure is proposed. The polyaddition of 2,2′-bis(trifluoromethyl)benzidine (TFMB) unsuccessful; specifically, reaction mixture remained inhomogeneous even after prolonged stirring. However, modified one-pot applicable OHADA/TFMB system. isolated PI powder form, as well those other OHADA-based PIs, highly soluble in numerous solvents afforded homogeneous stable solution with high solid content (20–30 wt%). Solution casting produced ductile film very glass transition temperature (Tg~300 °C). Furthermore, system exhibited remarkable thermal stability compared related TFMB-derived semi-cycloaliphatic PIs. contrary our expectations, this did not exhibit low linear coefficient expansion (CTE). This also possessed excellent thermoplasticity, probably reflecting its peculiar structure. use amide-containing diamine significantly enhanced Tg (355 °C) somewhat reduced CTE (41.5 ppm K−1) while maintaining optical transparency solubility.