Lc-Polyimides. 33. Poly(Ester-Imide)s of 4,4′-Diaminodiphenyl Ether Bistrimellitimide

Abstract The dichloride of 4,4′-diaminodiphenyl ether bistrimellitimide was polycondcnsed with numerous diphenols or diols in hot 1-chloro-naphthalene. The resulting poly(ester-imide)s were characterized by elemental analyses, inherent viscosities, 1H NMR spectroscopy, DSC and X-ray measurements. When hydroquinone, methylhydro-quinone, 2, 7-dihydroxynaphthalene, 4, 4′-dihydroxybiphenyl or 4,4′-dihydroxydiphenyl ether were used as building blocks, the poly(ester-imide)s decomposed before a mobile melt was obtained. Typical nematic Schlieren textures were observed with tert-butyl-hydroquinone or phenylhydroquinone monomers. A diphenol containing an aliphatic spacer yielded a smectic LC-phase, which was characterized by X-ray measurements with synchroton radiation up to 300°C. Attempts to obtain cholesteric poly(ester-imide)s by incorporation of isosorbide failed. The resulting chiral poly(esterimide)s were isotropic. Further poly(ester-imide)s were prepared from diphenols and 4,4′-diaminodiphenylmethane bistrimellitimide or 4,4′-diaminodiphenylsulfone bistrimellitimide. All these poly-(ester-imide)s formed isotropic melts. The pertinent structure-property relationships are discussed.