Colorless Semi-Alicyclic Copolyimides with High Thermal Stability and Solubility.

ABSTRACT: A series of colorless copolyimide films with high thermal stability and good solubility are synthesized from (trifluoromethyl)biphenyl-4,4'-diamine (TFMB) with different 1,2,4,5-cyclohexanetetracarboxylic dianhydride (HPMDA) to 2,2-bis(3,4-dicarboxyphenyl)-hexafluoropropane (6FDA) dianhydride mole ratios through one-pot solution polycondensation. These copolyimide films exhibit excellent optical transparency (T400 > 90% and λ0 ~305-333 nm) with a thickness of 15 μm and good solubility in most organic solvents. The excellent optical properties are mainly attributed to the low inter- and intra-molecular charge transfer interactions due to the alicyclic structure and the strong electronegative CF3 groups. The glass transition temperature increases from 332 to 352 °C with increasing HPMDA cont

SUBMITTER: Lan Z 

PROVIDER: S-EPMC6723692 | biostudies-literature | 2019 Aug

REPOSITORIES: biostudies-literature