2000 年 8 巻 1 号 p. 9-14
New tetracarboxylic acid dianhydride, which was norbornane-2:3, 5:6-tetracarboxylic dianhydride (NDA) was prepared by treatment of dicyclopentadiene (DCPD) with CO and methanol in the presence of catalystsand oxidizing agent. The stereochemistry of NDA was determined by x-ray analysis as an endo-exo form. Forthe application of NDA to industrial fields and polymer science, polyimide films (1 and 2) based on NDA and aromatic diamines have been synthesized to investigate their heat resistance and percent of transmissionof light. The percent of transmission of 1 and 2 are over 80%, which should be desired for practicalapplications in the field of polymer engineering such as liquid crystal display (LCDs), whereas the polymers (3 and 4) obtained from aromatic tetracarboxyic dianhydride such as a pyromellitic dianhydride instead of NDA was deep yellow, which is not desirable for high qualified display materials. The percent oftransmission of the deep yellow polymers (3 and 4) show 48 and 63.9%, respectively. On the other hand, thermal decomposition temperature of 1 and 2 are 462 and 445°C, respectively, which are lower by almost 30-70°C of these 3 and 4, respectively. Nevertheless, the thermal stabilities of 1 and 2 are still better than in many other polyimides of high-performance polymers.
