The Synthesis of Polyester-imides from 2, 7-Fluorenediol

Abstract

2, 7-Fluorenylene bis (trimellitate) dianhydride (FBTDA) was prepared by the solid phase condensation reaction of 4- (chloroformyl) phthalic anhydride with 2, 7-fluorenediol. Polyesterimides were synthesized by the bulk polycondensation reaction of FBTDA with aromatic diamines at high temperatures, and the reaction conditions were investigated. Also, polyesterimides were synthesized by the dehydration of polyamic acid polyesters at 200°C, which were prepared by the polycondensation reaction of FBTDA with aromatic diamines in DMF at a room temperature. As an aromatic diamine, p-phenylenediamine, 4, 4'-diaminodiphenylmethane, 4, 4'-diaminodiphenyl ether, 4, 4'-diaminodiphenyl sulfone, 2, 7-fluorenediamine or 2, 7-diamino9-fluorenone was used.
The polymer, C 1, are insoluble in such an organic solvent as DMF, DMA or DMSO, and slightly soluble in conc.1-12SO₄. Reduced viscosities of polymers increased with increasing reaction temperature. Reduced viscosities of polymers were measured in conc. H₂SO₄ solution at 30°C and their values are 0.07-0.30.
On the basis of the thermal analyses, it was found that these polymers decompose at 450, 550°C in a nitrogen atmosphere. The thermal stability of polyester-imides obtained by the bulk polycondensation reaction is superior to that obtained by the dehydration of polyamic acid polyester.