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An aromatic diamine monomer, 4,4′-bis(3-amino-5-trifluoromethyl phenoxy)-biphenyl (TFBPDA), was synthesized via the nucleophilic displacement reaction of 3,5-dinitrobenzotrifluoride and 4,4′-biphenol. The monomer was reacted with various aromatic dianhydrides via the high temperature polycondensation procedure to provide a series of polyimides. The polyimides, PI-1 to PI-4, show good solubility not only in aprotic solvents, such as N-methyl-2-pyrrolidinone and N,N-dimethylacetamide, but also in many common solvents, such as m-cresol, chloroform and cyclopentanone. PI-4, derived from 4,4′-(hexafluoroisopropylidene)diphthalic anhydride and TFBPDA, was even soluble in toluene. Moreover, PI films exhibit good thermal stability, outstanding transparency in the visible light region and acceptable mechanical and electrical properties. The excellent combined properties of the polyimides make them as a good candidate for fabricating microelectronics.  相似文献   
2.
An aromatic diamine monomer,4,4'-bis(3-amino-5-trifluoromethyl phenoxy)-biphenyl (TFBPDA),wassynthesized via the nucleophilic displacement reaction of 3,5-dinitrobenzotrifluoride and 4,4'-biphenol.The monomer wasreacted with various aromatic dianhydrides via the high temperature polycondensation procedure to provide a series ofpolyimides.The polyimides,PI-1 to PI-4,show good solubility not only in aprotic solvents,such as N-methyl-2-pyrrolidinone and N,N-dimethylacetamide,but also in many common solvents,such as m-cresol,chloroform andcyclopentanone.PI-4,derived from 4,4'-(hexafluoroisopropylidene)diphthalic anhydride and TFBPDA,was even soluble intoluene.Moreover,PI films exhibit good thermal stability,outstanding transparency in the visible light region and acceptablemechanical and electrical properties.The excellent combined properties of the polyimides make them as a good candidate forfabricating microelectronics.  相似文献   
3.
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.  相似文献   
4.
 Organo-soluble alicyclic polyimides (ALPIs) were synthesized from an alicyclic dianhydride, 1,8-dimethyl-bicyclo[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'-tetra-methy]-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'-benzo-phenonetetracarboxylic 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.  相似文献   
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