Abstract
3-Phenyl-tricyclo[6,2,2,O 2,7 ]dodeca-2,11-ene-5,6,9, 10-tetracarboxylic dianhydride was prepared from 1,1-diphenyl ethylene and maleic anhydride in 1 : 2 mole rato by [ 4 + 2]π Diels-Alder cycloaddition. The structure of the dianhydride was determined by mass spectroscopy, IR, 1 H-NMR, elemental analyses, and single crystal x-ray diffracton. The monomer was condensed with several diamines in N-methyl pyrrolidone or m-cresol. The polyamic acids and the polyimides synethesized has inherent viscosities in the range of 0.19-0.31 and 0.17-0.25 dL/g, respectively, measured in N-methyl pyrrolidone at 30°C. Both the polyamic acids and the polyamides were found to be soluble in m-cresol, N-methyl pyrrolidone, dimethylacetamide, dimethyl formamide, and dimethyl sulfoxide. The polyimides showed a low degree of crystallinity from wide ange x-ray diffraction. Thermal analysis of these polyimides revealed that their glass transition temperatures (T g ) were in the 215-237$GDRC range and they decomposed in two stages. The first-stage decomposition temperatures were almost the same in O 2 or N 2 atmospheres, but the polymers showed a better thermal stability in O 2 rather than in N 2 in the second stage. The mechanism of thermal degradation is discussed.