4

4-Bis(4-nitro-2-trifluoromethylphenoxy)diphenylether (p-6FNPE) was synthesized by the Williamson reaction between 4

4-dihydroxydiphenyl ether and 2-chlorine-5-nitro-trifluoromethyl benzene.Then

the reduction systems of Pd/C-hydrazine hydrate were adopted to obtain the corresponding products 4

4-bis(4-amino-2-trifluoromethylphenoxy)diphenylether (p6FAPE).Using three kinds of phenyl ether type trifluoromethyl-containing diamine

i.e.

1

4-bis(3-amino-5-trifluoromethylphenoxy)benzene (m6FAPB)

1

4-bis(4-amino-2-trifluoromethyl phenoxy)benzene (p-6FAPB) and p6FAPE

and two kinds of dianhydride

i.e.

3

3

4

4-oxydiphthalic anhydride (ODPA) and pyromellitic dianhydride (PMDA)

six kinds of fluorinecontaining polyimide (PI) films were prepared by the two-step method.The chemical structure and properties of the PI were characterized by FTIR

UVVis and TGA.The six kinds of fluorine-containing PI showed good solubility in aprotic polar organic solvents such as NMP

DMF and DMAc.PI obtained from mposition diamine showed better solubility.All the fluorine-containing PI films had good thermal stability

with a 5% weight loss temperature at 540℃ or higher.In the case of a same dianhydride

PI based on 6FAPE possessed higher thermal resistance than 6FAPB.Compared with PI based on PMDA

fluorine-containing PI films based on ODPA exhibited more excellent transparency in the visible wavelength range (400～700 nm)

and their transmittance at 450 nm was over 80%.PI based on p-6FAPB exhibited better transparency than p-6FAPE.PI films obtained from m-6FAPB tended to be colorless and transparent.The PI synthesized in this work could be expected to be used in the applications such as solar cell substrate and waveguide board materials.