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series of colorless and organosoluble poly(ether-imide)s (PEIs) were prepared from a phenylhydroquinone bis(ether anhydride), i.e., 2,5-bis(3,4-dicarboxyphenoxy)biphenyl dianhydride, and seven trifluoromethyl-containing bis(ether amine)s by the conventional two-stage process via the thermal or chemical imidization of the precursor poly(amic acid)s. The fluorinated PEIs prepared via the chemical imidization procedure had inherent viscosities of 0.46-1.27 dL/g and weight-average molecular weights of 68,000-87,500. The PEIs exhibited good solubility in a variety of organic solvents; they were readily soluble in amide-type polar solvents and chlorinated hydrocarbons on a concentration higher than 10%. The solution-cast films showed a high optical transparency and low color intensity, with an ultraviolet-visible absorption edge of 368-375 nm and a yellowness index of 5.9-9.9. These films were flexible and tough with tensile strengths of 89-114 MPa. They exhibited glass-tranisition temperatures of 198-250°C and 10% weight loss temperatures higher than 488°C in air or nitrogen. In addition, these PEI films also displayed low dielectric constants (3.22-3.52 at 1 MHz) and low moisture absorptions (0.22-0.73 wt%). [ABSTRACT FROM AUTHOR]

The thermal degradation behaviours of a novel aromatic poly(ester–imide) (PEI) derived from pyromellitic dianhydride and 2,7-bis(4-aminobenzoyloxy)naphthalene have been investigated by thermogravimetric analysis (TGA) and by pyrolysis–gas chromatography/mass spectrometry (pyrolysis–GC/MS). The weight of PEI fell slightly in the temperature range of 350–450 °C in the TGA analysis, but the major weight loss occurred at 520 °C. Evolve gas analysis (EGA) of the PEI showed maximum release of pyrolyzates at 550 °C. The chemical structure of the volatile products resulted from the PEI pyrolysis at different temperatures was identified by pyrolysis–GC/MS. The cleavage of the ester linkage within the polymer chain initiated at 350 °C, and bond scission in the partially hydrolyzed pyromellitimide unit occurred in the temperature range of 450–500 °C. The bonds within the pyromellitimide unit started to cleave at 550 °C. The extensive decomposition of the pyromellitimide segment within the polymer backbone occurred at 600 °C. The possible thermal degradation pathways of this PEI are proposed on the basis of the pyrolysis products. [ABSTRACT FROM AUTHOR]

Two new naphthalene-ring-containing bis(ester-amine)s, 2,3-bis(4-aminobenzoyloxy)naphthalene ( p- 2) and 2,3-bis(3-aminobenzoyloxy)naphthalene ( m- 2), were prepared from the condensation of 2,3-dihydroxynaphthalene with 4-nitrobenzoyl chloride and 3-nitrobenzoyl chloride, respectively, followed by catalytic hydrogenation. The novel aromatic poly(ester-amide)s and poly(ester-imide)s having 2,3-linked bis(benzoyloxy)naphthalene units have been synthesized from the polycondensation reactions of bis(ester-amine)s ( p- 2 and m- 2) or an equimolar mixture of 4,4′-oxydianiline and p- 2 or m- 2 with various aromatic dicarboxylic acids and dianhydrides. The synthesis of the poly(ester-amide)s was achieved by the phosphorylation polyamidation reaction by means of triphenyl phosphate, and the synthesis of the poly(ester-imide)s included ring-opening polyaddition to give poly(amic acid)s followed by chemical imidization to polyimides. Most of the poly(ester-amide)s were readily soluble in various organic solvents. Six poly(ester-amide)s and two poly(ester-imide)s derived from less rigid diacids and dianhydrides, respectively, were amorphous and could be solution-cast into transparent and tough films with good mechanical properties. Most of the poly(ester-amide)s displayed discernible glass-transition temperatures ( T gs) between 192 and 223 °C in the DSC traces. All of the poly(ester-imide)s, except for one sample, showed clear T g values between 225 and 265 °C by DSC. These poly(ester-imide)s showed excellent thermal stability with 10 wt% loss temperatures above 460 °C in nitrogen or air. [ABSTRACT FROM AUTHOR]

Two series of new blue photoluminescent aromatic polyesters (polyarylates) were synthesized from 4,4′-dicarboxytriphenylamine and 4,4′-dicarboxy-4″-methyltriphenylamine with various bisphenols by the diphenylchlorophosphate (DPCP) activated direct polycondensation in a medium of pyridine and lithium chloride. These polymers were amorphous and readily soluble in various common organic solvents including DMAc, THF, and chloroform, and could be cast from their chloroform solutions into transparent films due to their excellent solubility. These polyarylates exhibited moderately high T g values (186–264 °C) and thermal stability. In THF solution, these triphenylamine-containing polyarylates showed UV-Vis absorption bands at 359–365 nm and photoluminescence peaks around 427–451 nm in the blue region. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

A new series of polyarylates containing carbazolyl-substituted triphenylamine units were synthesized by direct polycondensation of 4.4′-dicarboxy-4′-N-carbazolyltriphenylamine with various bisphenols. All polymers were highly soluble in various common organic solvents and could afford tough, transparent, and colorless films by solution casting. These amorphous and organo-soluble polyarylates showed no significant decomposition below 470 °C in both nitrogen and air atmospheres with glass transition temperatures (Tg) ranging from 234 to 287 °C. In THF solution, these polyarylates exhibited blue photoluminescence around 464-476 nm with quantum yield up to 28%. The photoluminescence exhibited solvent effect and was red-shifted in the polar solvent at room temperature. [ABSTRACT FROM AUTHOR]

A novel trifluoromethyl-substituted bis(ether amine) monomer, 1,1-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]-1-phenyl-2,2,2-trifluoroethane, was synthesized that led to a series of novel fluorinated polyimides via chemical imidization route when reacted with various commercially available aromatic tetracarboxylic dianhydrides. These polyimides were highly soluble in a variety of organic solvents such as N-methyl-2-pyrrolidone and N, N -dimethylacetamide, and most of them could afford transparent, low-colored, and tough films. These polyimides exhibited glass-transition temperatures ( Tgs) of 227-269 °C and showed no significant decomposition below 500 °C under either nitrogen or air atmosphere. These polyimides had low dielectric constants of 2.87-3.17 at 10 kHz, low water uptake of 0.13%-0.58%, and an ultraviolet-visible absorption cutoff wavelength at 364-410 nm. For a comparative study, a series of analogous polyimides based on 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenyl-2,2,2-trifluoroethane were also prepared and characterized. [ABSTRACT FROM AUTHOR]

2,4-diaminotriphenylamine (2) was synthesized via the cesium fluoride-mediated aromatic substitution reaction of 1-fluoro-2,4-dinitrobenzene with diphenylamine, followed by palladium-catalyzed hydrazine reduction. A series of poly(amide-imide)s (PAIs) with inherent viscosities of 0.38–0.46 dL/g were prepared by triphenyl phosphite-activated polycondensation from the diamine monomer 2 with various monoimide- and diimide-dicarboxylic acids. All of the PAIs were readily soluble in a variety of organic solvents and formed strong and tough films via solution casting. These PAIs have moderately high glass transition temperatures in the range of 168–274 ○C and 10 % weight loss temperatures in excess of 447 ○C in nitrogen or in air. [ABSTRACT FROM AUTHOR]

Studies synthesis and properties of fluorinated polyamides based on 2,7-bis(4-amino-2-trifluoromethylphenoxy)naphthalene. Method of the study; Results and discussion; Conclusion.

A series of fluorinated polyimides were prepared from 1,1-bis[4-(4-aminophenoxy)phenyl]-1-2,2,2-trifluoroethane with various aromatic tetracarboxylic dianhydrides via a conventional two-step procedure. These polyimides were amorphous in nature and afforded flexible and tough films. Some polyimides derived from less stiff dianhydrides were soluble in polar organic solvents. The glass-transition temperatures (Tg) of these polyimides ranged from 252 to 324°C, and softening temperatures (Ts) stayed in the 254∼322°C range. Decomposition temperatures (Td) at 10% weight loss all occurred above 569°C in both air and nitrogen atmospheres. For a comparative study, another series of analogous polyimides based on 1,1-bis[4-(4-aminophenoxy)phenyl]-1-phenylethane were also prepared and characterized. [ABSTRACT FROM AUTHOR]

Presents a study that designed a novel class of organosoluble and strictly alternating poly(amine-amide-imide)s containing triphenylamine units in the main chain. Experimental procedures; Results of the study; Conclusions.