Soluble aromatic polyimides and polyamides based on 4,4′‐diaminotriphenylmethane

Abstract

SYNOPSISAromatic polyamides and polyimides were synthesized from 4,4'-diaminotriphenylmethane (DA-TPM) for studying their solubility, thermal, and mechanical properties. The polymers were found to be soluble in amide solvents and pyridine, and this could be attributed to the practically free rotation of the polymer chain segments around the bridging group within the DA-TPM and the effect of its pendant phenyl ring. The polyimides and polyamides exhibited well-distinguished glass transition in the range of temperatures, which is typical for flexible-chain polymers. For the polyimides, significant differences in solubility and mechanical properties were observed between the samples prepared by chemical and thermal imidization of poly(amic acids). Thermal imidization brought about remarkably less soluble brittle films. 0 1995 John Wiley & Sons, Inc.

A solid‐state NMR study of aromatic polyimides based on 4,4′‐diaminotriphenylmethane

“…17 For PI-TPMs obtained from the chemical imidization of PAA or from the one-step high-temperature polycondensation, the inherent viscosity ranged from 0.4 to 1.4 dL/g depending on the structure of the anhydride moiety. 2,3 The molecular weight of PMDA-ODA was characterized by measuring the inherent viscosity of the corresponding precursor PAA (0.5 g/dL DMF solutions at 25°C). The obtained inh was 2.5 dL/g.…”

“…The monomer 4,4-diaminotriphenylmethane (DA-TPM) was prepared by the reaction of aniline with benzaldehyde at 140°C under a nitrogen flow. 2,3,10,11 Polymer-grade DA-TPM (mp 126°C) was obtained by repeating the recrystallization of the crude product from benzene followed by sublimation at 110°C and 10 Ϫ4 mmHg.…”

“…Films were obtained by casting these solutions onto glass plates and drying first at 230°C and 10 Ϫ6 mmHg for 15 h and then at 275°C for 30 min to remove the residual solvent. 2,3 Poly[N,NЈ-bis(phenoxyphenyl)pyromellitimide] (PM-ODA) was obtained by the acylation of 4,4Јoxydianiline with PMDA in NMP at room temperature for 4 h followed by thermal imidization of the resulting PAA in a condensed state (as a film) at 300°C for 30 min. The used nomenclature of the PI-TPMs is based on the dianhydride moiety as PM-TPM, BSA-TPM, ODP-TPM, BZP-TPM, and BP-TPM.…”

“…A low-temperature condensation with both pyromellitic or 3,3Ј,4,4Ј-oxydiphthalic anhydrides yielded high molecular weight poly(amic acid)s, but further thermal imidization in the condensed state resulted in fragile and insoluble polyimides. 1 In a recent article, 2 it was shown that these drawbacks can be overcome if thermal imidization is replaced by a chemically induced process at room temperature. The obtained polymers (PI-TPM) possessed a good solubility in organic solvents.…”

Polyimides Based on 4-4’-Diaminotriphenylmethane (DA-TPM)

“…4-4'-Diaminotriphenylmethane (DA-TPM) and its derivates, have attracted the attention of our research group as monomers for the synthesis of various rigid-rod polyamides (PAs) and PIs. [23,24] The pendant phenyl ring and practically free internal rotation of the triphenylmethane bridging group predicted from the theoretical calculations make DA-TPM an excellent candidate for synthesis of processable PAs and PIs without sacrificing the high thermal stability. [23] Earlier research carried out for the structurally similar N,N-diamine triphenylamine (DA-TPA) showed that the incorporation of a pendant phenyl group into the polymer backbone is a successful approach to increase solubility and processability of PIs.…”