New AB Polyetherimides Obtained by Direct Polycyclocondensation of Aminophenoxy Phthalic Acids

Abstract

The one-pot, high temperature, catalytic synthesis of polyetherimides (PEIs) in molten benzoic acid was investigated. The synthesis was conducted using the AB monomers, 4-aminophenoxy phthalic acid (IIa) and 3-aminophenoxy phthalic acid (IIb). Both Homo and co-PEIs with different ratios of substituted AB IIa and IIb were prepared and characterized by Fourier transform infrared spectroscopy, differential scanning calorimetry and wide angle X-ray diffraction. The solubility of the polymers in a variety of solvents was also investigated. Homo-poly-lib is an amorphous thermoplastic that is soluble in CHC13 DMS8 and amide-type solvents. Homo-poly-IIa has a locally ordered structure and is insoluble. Properties of the IIa/IIb copolymers depend strongly on their composition. When the IIa/Hlb ratio is 30: 70 or less, co-PEIs behave as thermoplastic substances soluble in chloroform. At an IIa/lIb ratio in the starting mixture of 40: 60 or higher, the properties of co-PEIs are similar to that of poly-IIa.

Study on thermal behaviors of a novel cruciform amide-containing phthalonitrile monomer

“…[28]. 2,2′,5,5′-biphenyl tetraacyl chloride was synthesized according to a previous published procedure with minor modification.…”

Synthesis of reactive three‐arm star‐shaped oligoimides with narrow molecular weight distribution

“…The synthesis of star‐shaped oligoimides (SOI) was carried out according to the В3+АВ′ scheme by the method of high‐temperature catalytic polycondensation in molten benzoic acid. Previously, this method was used for the synthesis of various linear homo polyimides, including PI from AB monomers, random and block copolyimides, and HB polyimides . When using APPA as AB′ monomer, the mechanism of the process includes in situ transformation of phthalic acid fragment to phthalic anhydride followed by bimolecular reaction of amino and anhydride groups to form thansient amic acid moiety and its subsequent imidization to imide cycle.…”

“…In present work, we attempted to implement the “slow addition monomer” approach to produce 3‐arm oligoimide stars with narrow MWD. Previously, we developed a method of synthesis of polyimide (PI) by a single‐stage polycondensation of 3‐aminophenoxy phthalic acid (AB′ monomer) in the “catalytic solvent”—molten benzoic acid . Methodological difference of this work from ref.…”

“…Methodological difference of this work from ref. is that (1) synthesis is carried out in the presence of small quantity of three‐functional amine, and (2) AB′ is introduced slowly.…”

Achievements in polycondensation and condensation polymers

“…Kuznetsov et al showed that the synthesis of PIs, including branched PIs, efficiently occurs in the molten benzoic acid, which serves as an active medium during the formation of these types of poly mers [55][56][57][58][59].…”