【摘 要】
：
Organo-soluble alicyclic polyimides (ALPIs) were synthesized from an alicyclic dianhydride, 1,8-dimethylbicyclo[2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhyd
【机 构】
：
Laboratory of Advanced Polymer Materials,Institute of Polymer Science and Technology
论文部分内容阅读
Organo-soluble alicyclic polyimides (ALPIs) were synthesized from an alicyclic dianhydride, 1,8-dimethylbicyclo[2.2.2] oct-7-ene-2,3,5,6-tetracarboxylic dianhydride (DMEA) and several multialkyl-substituted 4,4′-diaminodiphenylmethane compounds, including 3,3′-dimethyl-4,4′-diaminodiphenyl methane (DMDA), 3,3′,5,5′-tetramethyl-4,4′-diaminodiphenyl methane (TMDA) and 3,3′,5,5′-tetraethyl-4,4′-diaminodiphenylmethane (TEDA). For comparison, the aromatic polyimides (ARPIs) were synthesized from the aromatic dianhydride, 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) and the same diamines. The ALPIs exhibited better solubility and transparency,but worse thermal stabilities and mechanical properties than those of the ARPIs. And the ALPIs could be dissolved in common organic solvents, such as N-methyl-2-pyrrolidinone (NMP), N,N-dimethylformamide (DMF), N,N-dimethylacetamide (DMAc), chloroform, tetrahydrofuran, m-cresol and so on. The ALPI films had an UV-Vis cut-off at 320 nm and a transmittance of higher than 80% in the visible region. In addition, the ALPIs showed thermal decomposition temperatures (Td) of about 450℃, which was nearly 100℃ lower than that of the ARPIs.
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