Poly(ether-imide) thin films with/without fluorine in the structure

Thin films, in the range of tens of micrometers thickness, have been prepared by casting onto glass plates the N-methylpyrrolidone solutions of two poly(ether imide)s containing isopropylidene or hexafluoroisopropylidene groups. The polymers have been synthesized by polycondensation reaction of 4,4´-(1,3-phenylenedioxy) dianiline, with 2,2-bis[(3,4-dicarboxyphenoxy) phenyl] propane dianhydride or 1,1,1,3,3,3-hexafluoro-2,2-bis [(3,4-dicarboxyphenoxy) phenyl]propane dianhydride. They were easily soluble in polar aprotic solvents and showed high thermal stability. The surface properties of the poly(ether imide) thin films such as dynamic contact angles, contact angle hysteresis, and water vapours sorption capacity were evaluated in correlation with their structure. The dielectric spectroscopy in the frequency range of 10^-1-10⁶ Hz and at temperature range from 100degC to 175degC was employed to study the electrical behaviour of polymer films.