LC-POLYIMIDES - 33 - POLY(ESTER-IMIDE)S OF 4,4'-DIAMINODIPHENYL ETHERBISTRIMELLITIMIDE

The dichloride of 4,4'-diaminodiphenyl ether bistrimellitimide was pol ycondensed with numerous diphenols or diols in hot 1-chloronaphthalene . The resulting poly(ester-imide)s were characterized by elemental ana lyses, inherent viscosities, H-1 NMR spectroscopy, DSC and X-ray measu rements. When hydroquinone, methylhydro- quinone, 2,7-dihydroxynaphtha lene, 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 w ith 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 30 0 degrees C. Attempts to obtain cholesteric poly(ester-imide)s by inco rporation of isosorbide failed. The resulting chiral poly(esterimide)s were isotropic. Further poly(ester-imide)s were prepared from dipheno ls and 4,4'-diaminodiphenylmethane bistrimellitimide or 4,4'-diaminodi phenylsulfone bistrimellitimide. All these poly(ester-imide)s formed i sotropic melts. The pertinent structure-property relationships are dis cussed.