| abstract |
Copolyamic acids carrying -CF3 group functionalized aromatic segments in the polymer chain derived from aromatic diamines and dianhydrides with linear-rigid-planar structure interrupted by linear-rigid-noncoplanar segments structure and the corresponding copolyimides films are provided. These copolyimides have low in-plane thermal coefficient of expansion, reduced anisotropy in the optical and dielectric properties, low moisture uptake, and improved polyimide-to-polyimide adhesion. |