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Phenylphosphine oxide-containing poly(arylene ether imide)s, poly(arylene ether quinoxaline)s, poly(arylene ether benzoxazole)s and poly(arylene ether benzothiazole)s were prepared by reacting the appropriate difluoro heterocyclic compound with bis(4-hydroxyphenoxy-4′-phenyl)phenylphosphine oxide. The polymers exhibited glass transition temperatures from 209 to 255°C and inherent viscosities from...
Phenylphosphine oxide-containing polyimides, poly(arylene ether 1,3,4-oxadiazole)s and poly(arylene ether benzimidazole)s were prepared and evaluated for resistance to an oxygen plasma. Thin films of the phenylphosphine oxide-containing polymers were exposed to a radiofrequency-generated oxygen plasma under vacuum along with Kapton ® HN and polymers of similar chemical structure that did not...
Polyamides and polyimides having 4,4 -o-terphenyldiyl units in the main chain were synthesized. The polyamides were prepared from 4,4 -diamino-o-terphenyl and aromatic dicarboxylic acids or aromatic dicarbonyl dichlorides. The polyimides were prepared from 4,4 -diamino-o-terphenyl and aromatic tetracarboxylic dianhydrides. Copolyamides and copolyimides were also prepared using 4,4 -diamino-o-terphenyl...
Polyimides were prepared from α,ω-bis(4-aminophenoxy)alkanes and various aromatic tetracarboxylic anhydrides. Only the polyimides derived from biphenyl-3,3 ,4,4 -tetracarboxylic anhydride form a liquid crystalline (LC) melt. In contrast, polyimides of the same dianhydride and α,ω-diamino alkanes are crystalline but not thermotropic. The mesogenic and non-mesogenic behaviour of the various poly(ester-imide)s...
Imide ring formation upon heat treatment of diacylated diamines and dianhydrides was shown to be highly efficient. Evidence to support this conclusion was obtained from thermal gravimetric analysis, differential scanning calorimetry and infra-red spectroscopy. Equimolar mixtures of diacylated diamines and dianhydrides form eutectic mixtures, which quantitatively eliminate the corresponding acid...
The synthesis of amorphous, soluble triarylphosphine oxide-containing imide oligomers and arylene ether sulfone triarylphosphine oxide copolymers is described. The imide oligomers were controlled-molecular-weight systems endcapped with 3-phenylethynyl aniline. The arylene ether copolymers were synthesized in high molecular weight with controlled amounts of a novel comonomer, which contained pendent...
3,3-Bis[4-(4-aminophenoxy)phenyl]phthalimidine (2) was used as the monomer with various aromatic dicarboxylic acids and tetracarboxylic dianhydrides to synthesize polyamides and polyimides, respectively. The diamine 2 was derived by a nucleophilic substitution of 3,3-bis(4-hydroxyphenyl)ptthalimidine withp -chloronitrobenzene in the presence of K 2 CO 3 and then reduced by hydrazine...
Novel regular network aliphatic-aromatic and aromatic polyimide films were prepared from mellitic acid (Y H ) and aliphatic and aromatic diamines or diisocyanates. Prepolymers prepared by solution polycondensation were cast and successively post-polymerized to form a network. The resultant films were insoluble in any organic solvents. The heat distortion temperature (T h ) and density...
A means of generating high temperature polymer foams which leads to pore sizes in the nanometre regime has been developed. Foams were prepared by casting block copolymers comprising a thermally stable block and a thermally labile material, such that the morphology provides a matrix of the thermally stable material with the thermally labile material as the dispersed phase. Upon a thermal treatment...
An investigation was carried out to improve polyimide processability via internal plasticization. This approach entailed the synthesis of a series of diamines in which the length of the alkyl group in alkyl 3,5-diaminobenzoates was varied from one to eighteen carbons. The polyimides obtained from several of these diamines were found to have increased solubility, a lower glass transition temperature...
Several semicrystalline poly(aryl ether ketone)s (PEK, PEEK and different isomers of PEKK) were melt-blended at T > 400°C with three high temperature thermoplastic polyimides. The compatibility and crystallization properties of the blends were studied by differential scanning calorimetry (d.s.c.). Blends of a semicrystalline New-Thermoplastic PolyImide (N-TPI) showed some surprising differences...
Composite membranes with an ultra-thin polyimide separation layer have been prepared by the deposition of dimethylalkylammonium salt of polyamic acid on a poly(phenylene oxide) porous support layer by the Langmuir-Blodgett technique and subsequent thermal cyclization of the polyimide precursor. In spite of a relatively mild thermal treatment, complete cyclization was achieved as observed by Fourier...
New aromatic polyamides and polyimides containing benzimidazole or benzoxazinone pendent groups were prepared from 5-(2-benzimidazole)- or 5-(2-benzoxazinone)-1,3-phenylenediamine. They were characterized by inherent viscosity and water absorption measurements, Fourier transform infra-red, 1 H nuclear magnetic resonance, X-ray, thermomechanical, thermogravimetric and isothermal gravimetric...
The gas permeability and permselectivity properties were investigated of polyimides, prepared from 3,3 ,4,4 - and 2,2 ,3,3 -thiaphthalic dianhydride (p-TDPA and m-TDPA, respectively), or 1,4-bis(3,4-dicarboxyphenoxy)- and 1,4-bis(2,3-dicarboxyphenoxy) benzene dianhydride (p-HQDPA and m-HQDPA, respectively), and 4,4-oxydianiline. The polyimides prepared from meta-dianhydrides, which have lower...
Two new diamines, 1-(1-naphthoxy)-2,4-diaminobenzene and 1-(biphenylyl-4-oxy)-2,4-diaminobenzene, were synthesized and used for the preparation of modified polyamides and polyimides bearing bulky ether groups. Their properties were compared with those of the corresponding unmodified polymers. Characterization of polymers was accomplished by inherent viscosity measurements, Fourier transform infra-red,...
A series of aromatic ether diamines having different numbers of benzene rings, different amino-substituted positions and different moieties in their structures was synthesized. By using these synthesized ether diamines and commercially available tetracarboxylic dianhydrides, various kinds of polyimides having almost the same molecular weights were synthesized. The glass transition temperature (T...
Molecular dynamics (MD) simulations were used to investigate the transport of different gases in a poly(amide imide) (PAI) and two polyimides (PI1 and PI2). The agreement between measured and simulated average diffusion coefficients (D) was acceptable. There was, however, a considerable scattering of the D values for the individual simulated gas molecules. While MD simulations are still not an ideal...
4,3 -Diamino-3,5-diphenyl-biphenyl and 4-amino-4 -carboxy-3,5-diphenyl-biphenyl were synthesized from the corresponding pyrylium slats. A novel class of rigid-rod polyamides and polyimides containing phenyl pendent groups were synthesized and characterized by viscosities, elemental analyses, 1 H n.m.r., 13 C n.m.r., X-ray, t.m.a., t.g.a. and isothermal gravimetric analysis...
The cure behaviour of the ethyl ester derivatives of 4,4′-oxydianiline (ODA)/pyromellitic dianhydride (PMDA) poly(amic acid) to the corresponding imide was investigated using isothermal and dynamic mass spectroscopy, FT-Raman spectroscopy and density gradient column analysis. Both the rate cure and per cent conversion were dependent on the isomer composition, occurring in the order para >meta >...
2,2′-Bis(3,4-dicarboxyphenoxy)-1,1′-binaphthyl dianhydride was used as a new monomer with various aromatic diamines to obtain polyimides by the usual two-step method. The bis(ether anhydride) was prepared by a nucleophilic substitution of 1,1′-bi-2-naphthol with N-phenyl-4-chlorophthalimide, N-methyl-4-nitrophthalimide or 4-nitrophthalonitrile in aprotic polar solvent, and subsequent hydrolysis of...
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