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The synthesis and characterization of three new imide oligomers from acridine yellow, using pyromellitic dianhydride (PMDA), 3,3′,4,4′-benzophenone tetracarboxylic acid dianhydride (BTDA) and 2,2′-bis(3,4-dicarboxyphenyl) hexafluoropropane dianhydride (6FDA), is reported in this paper. Due to the poor reactivity of acridine yellow, a two-step synthesis technique at lower temperature produced little...
New results of molecular modelling investigations on the transport of different small molecules in polyimides and polysiloxanes are discussed. The transition state Gusev-Suter Monte Carlo method reveals a reasonable coincidence between simulated and measured diffusivity and solubility values for the polyimides. A comparison between simulation data obtained for flexible chain polymers like poly(dimethyl...
1,4-Bis(4-aminophenoxy)trimethylbenze (3a) and 1,4-bis(4-aminophenoxy)-2,5-di-t-butylbenzene (3b) were synthesized in two steps from the hydroquinones via nucleophilic aromatic substitution and catalytic reduction. Aromatic polyamides were synthesized from these diamines by direct polycondensation with various diacid chlorides or by reaction with diacids, triphenyl phosphite and pyridine in N-methyl-2-pyrrolidinone...
This work reports the synthesis of new diamantane-based polyimides by the reaction of 4,9-diaminodiamantane (I) with various aromatic tetracarboxylic dianhydrides. The polyimide film IV a has a low dielectric constant of 2.7 and a low moisture absorption of 0.205%. The number-average molecular weight (M n ) of polyimide IV a is 37 kg/mol. Dynamic mechanical analysis (DMA)...
Physical properties of thin films of soluble and insoluble aromatic polyimides were compared by d.s.c., u.v.-visible and fluorescence spectroscopy, and prism coupler technique. D.s.c. results showed that the thermal properties of insoluble polyimides are superior to those of soluble ones, owing to the specific molecular interactions of insoluble polyimides, revealed by fluorescence spectroscopy. However,...
A series of novel polyimides have been synthesized from the condensation of 5-(perfluorononenyloxy)isophthalic acid bis(4-aminophenyl) ester (IV 3 ) with various aromatic tetracarboxylic dianhydrides. For comparison, the polyimides containing the bis(4-aminophenyl) ester unit were prepared from terephthalic acid bis(4-aminophenyl) ester (IV 1 ) and isophthalic acid bis(4-aminophenyl)...
Poly(amic diethyl ester) [PAE] precursors of four different polyimides with various chain rigidities were synthesized and thermally converted to the polyimides in thin films: rodlike poly(p-phenylene pyromellitimide) [PMDA-PDA] and poly(4,4'-biphenylene pyromellitimide) [PMDA-BZ], pseudo-rodlike poly(p-phenylene biphenylenetetracarboximide) [BPDA-PDA] and semiflexible poly(4,4-oxydiphenylene pyromellitimide)...
A new diamine, 1,1-bis[4-(4-aminophenoxy)phenyl] cyclododecane (BAPCD), bearing flexible ether and bulky pendant cyclododecylidene groups was prepared in three steps from cyclododecanone. The monomer was reacted with six conventional aromatic dianhydrides in N,N-dimethylacetamide (DMAc) to obtain the corresponding new polyimides via the poly(amic acid) precursors and thermal or chemical imidization...
3,3 - Di(4-aminophenyl)-5,5 - di(4-biphenylyl)-p-terphenyl and 3,3 - di(4-aminophenyl)-5,5 , 6,6 - tetraphenyl-p-terphenyl as well as the corresponding acid chlorides were synthesized through pyrylium salts. The polyamides and polyimides prepared from them were characterized by inherent viscosity, elemental analyses, FTIR, UV-vis, 1 H-NMR, 1 ...
A novel dianhydride, 3,3'-dioxo-[1,1']-spirodiphthalan-5,5',6,6'-tetracarboxylic dianhydride, was synthesized and used as a monomer to prepare polyimides with several diamines via a conventional two-stage procedure. The intermediate poly(amic-acid)s had inherent viscosities of 0.84-1.71dL/g and could be thermally converted into lightly yellow, transparent, flexible and tough films. Films cast from...
New condensation monomers—primarily diamines containing phenoxy, thiophenoxy and phenylsulphone substituents were obtained from 2,4,6-trinitrotoluene (TNT). Interaction of some dinitro compounds containing strong electron-withdrawing groups in meta-positions with bis-phenols under conditions of aromatic nucleophilic polynitro substitution reactions led to the formation of aromatic oligoethers. Based...
The electrochemical and electrochromic properties of poly(ether naphthalimide)s were studied and compared with related model compounds. The electroactive sites within the poly(ether naphthalimide)s were identified to be ketone and imide groups. The stepwise coloration process, colorless-red-dark blue corresponding to the neutral, radical anion and dianion species, was found to be related to the first...
Nonlinear optical (NLO) polymers with glass temperatures (T g ) as high as 291 o C were prepared, PI 2-4 by covalent bonding of a chromophore to the backbone of hydroxyl polyimides via a Mitsunobu reaction, PI 1 as a donor-embedded polyimide was synthesised by polycondensation of a diaminochromophore and 4,4'-(hexafluoroisopropylidene) diphthalic anhydride in a two-step reaction. Poled...
The new five benzene rings-containing diamine, α,α'-bis[3,5-dimethyl-4-(4-aminophenoxy)phenyl]-1,4-diisopropylbenzene (BDAPD) was prepared by the aromatic nucleophilic substitution of α,α'-bis(4-hydroxy-3,5-dimethylphenyl)-1,4-diisopropylbenzene with 1-chloro-4-nitrobenzene, and subsequent hydrogenation of the intermediate dinitro. The diamine was reacted with various aromatic dianhydrides to prepare...
Starting from 1,4-diaminobutane and trimellitic anhydride a bisimide dicarboxylic acid was prepared which was transformed into its diethyl ester. This imide monomer was polycondensed with mixtures of 1,4-dihydroxybutane and poly(tetramethylene oxide) (PTMO) diols having number average molecular weights (Mns) of 650, 1000 or 2000Da. For each PTMO diol, the weight fraction of the hard segments was varied...
The physical and gas transport properties of homo-polyimides, 6FDA-durene and 6FDA-2, 6-diaminotoluene (2,6-DAT), and their copolyimides, 6FDA-durene/2,6-DAT with different diamine ratios, were characterized. The glass transition temperatures of the copolyimides obtained from DSC experiments were about 6–10°C lower than that calculated from the Fox equation. The experimental results for the gas permeability,...
Functionalised second-order nonlinear optical (NLO) polyimides have been developed. The key challenge in our approach was a one-step synthesis of these polymers, by reaction of di(hydroxyalkyl) chromophores and diimides utilising the Mitsunobu reaction. Glass transition temperatures in the range of 205–224°C were obtained. Thin spincoated films of the polymers were corona-poled and analysed by second-harmonic...
Argon plasma-pretreated polyimide (PI, Kapton ( R) HN) films were subjected to UV-induced surface graft copolymerization with N,N'-(dimethylamino)ethyl methacrylate (DMAEMA) and 2-(trimethylammonium)ethyl methacrylate chloride (TMMAC). The DMAEMA graft-copolymerized PI (DMAEMA-g-PI) surfaces were also quaternized and amino-functionalized with 3-bromopropylamine hydrobromide (the Q-DMAEMA-g-PI...
A series of new polyimides were prepared from the reaction of 2,3,3',4'-biphenyltetracarboxylic dianhydride (a-BPDA) with various aromatic diamines. The properties of the a-BPDA polyimides were compared with those of polyimides prepared from the reaction of 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA) with the same aromatic diamines. Films of the a-BPDA polyimides had higher glass transition...
A series of aromatic poly(ether imide)s containing 9,9′-spirobifluorene moieties in the main chain have been synthesized via the polycondensation of 2,2′-bis(4-aminophenoxy)-9,9′-spirobifluorene with a variety of aromatic dianhydrides. In the diamine monomer, the two aminophenoxyfluorene entities are orthogonally arranged and are connected through an sp 3 carbon atom (the spiro center). The...
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