Optically transparent (co)polyimides based on alicyclic diamines with improved dielectric properties

It was shown that the optical and dielectric properties of polyimides (PIs) are affected by both the presence of an alicyclic fragment and the non-coplanarity of the structural elements of the polymer chain. The combination of these factors contributed to an increase of the transparency of the PIs in the optical range and a decrease of the dielectric constant. It was determined that the introduction of 20 mol.% adamantane-containing diamine into the PI structure contributed to its more complete amorphization and increased its transparency.