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The novel gas separation membranes have been prepared by blending highly gas permeable polymer of intrinsic microporosity (PIM-1) and with Troger's Base polymer (TB). Interestingly, it was found firstly that the PIM-1 polymer was miscible with Troger's Base polymer in any proportion. It was assumed that the excellent compatibility between two polymers could be attributed to the interaction between CN group in PIM-1 and N atoms in Troger's Base moieties, as confirmed by ATR-IR results. Thus, flexible, tough and transparent blending membranes (PIM/TB) at different compositions between PIM-1 and TB were obtained by solution casting. The SEM results further confirmed the homogeneous morphology of blending membranes, indicating the excellent compatibility between two polymers. The gas separation performance testing by the volume-constant method suggested that the PIM/TB blending membrane showed lower pure gas permeability but higher ideal permselectivity than that of the pristine PIM-1 membrane, probably due to the lower d-spacing of TB polymers from commercial aromatic diamine which has a rotatable bond as confirmed by XRD results. The highest ideal permselectivity of CO2/CH4 was obtained for PIM/TB (6:4) membranes with CO2 permeability of 2585Barrer. Moreover, the excellent anti-plasticization ability of CO2 was observed for the blending membranes. The temperature dependence of gas separation and ideal permselectivity had also been observed for the membranes. The results suggested that the ideal permselectivity, particularly for the CO2/N2 and CO2/CH4 at lower temperature were much higher than that of the membrane at high temperature in spite of the decreasing permeability of CO2. The highest ideal permselectivity was achieved as high as 54.3 for CO2/N2 at − 25 ℃ for PIM/TB(8:2) membrane. Thus, the strategy of blending Troger's Base with PIM-1 showed a promising approach for high performance gas separation membrane.

The aromatic epoxy isomers triglycidyl p-aminophenol and triglycidyl m-aminophenol were cured with two aromatic diamine isomers 4,4′ diaminodiphenyl sulphone and 3,3′ diaminodiphenyl sulphone, creating four variations of epoxy resin. Dynamic and static mechanical analyses were used to understand the influence of chemical and network structure on the thermal, volumetric and mechanical properties of the epoxy resin. Fracture toughness increases are observed for networks containing meta substituted phenylene ring amines compared to the para equivalents, however no difference is noticed when the meta substituted phenylene ring epoxy is used. Use of meta substituted phenylene rings increases glassy modulus, yield stress, density and strain to failure. Correspondingly, decreases are seen in the glass transition temperature, intensity of the beta transition and the rubbery modulus. The results are entirely consistent with internal antiplasticisation caused by the presence of the meta substituted phenylene rings.

Organic light-emitting diodes based on multiple-quantum-well (MQW) structures consisting of regular placement of N, N′-Di (1-naphthyl)-N, N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine (NPB) and bathocuproine (BCP) layers have been fabricated. The findings show that the QWs structure can intensely raise the quality of OLED results. Compared with conventional device performance without MQW structure, the external quantum efficiency, current efficiency, and luminance of the OLED with two periods of QWs have been severely increased up to 1.77%, 25.40 cd/A, and 8686 cd/m2, respectively. These improvements in results are attributed to the enhanced hole-electron balance, owing to utilizing the MQW structure.

We have developed a novel route for the synthesis of high-performance bio-polyimides (PIs) microbially-derived from photo-responsive aromatic diamine 4,4′-diaminostilbene (DAS) and its reduced counterpart 4, 4′-(ethane-1,2-diyl)dianiline (EDDA). DAS and EDDA were condensed with various commercially-available dianhydrides to obtain a series of poly(amic acid)s (PAAs) and PIs which were characterized in terms of their thermal, mechanical, and photo-functions. These bio-based PAAs showed a very high viscosity of 6.62 dL/g, and the PIs showed ultrahigh thermal resistance with Td10 values over 600 °C, which were higher than that of any bio-based plastic reported thus far. They also showed Tg values above 250 °C, and tensile strength of over 132 MPa, which is higher than that of Kapton™. The PIs also showed photo-functional behavior based on stilbene-based photoreactions.

A new tri-functional phthalonitrile monomer tris(3-(3,4-dicyanophenoxy)phenyl) phosphate (TPP) was first synthesized and characterized with the intent of increasing the cross-linking rate of phthalonitrile resins. By combining TTP and di-functional phthalonitrile with aromatic diamine easy-processable formulations (η 450 °C, T5% > 500 °C, TOS5% > 500 °C, Yc at 900 °C > 80%). TPP, the introduced monomer, can be used as a stiffness increasing additive with common di-functional phthalonitriles, and easy-processable formulations for cost-effective techniques of composites manufacturing.

Chemical cross-linking of super-growth carbon nanotubes was performed to increase bucky gel actuators efficiency in transferring motion from the nano-scale to the micro-scale. The modification was achieved by a three-step reaction i.e. first an oxidation with nitric acid, then a chlorination process with thionyl chloride and finally the cross-linking with an aromatic diamine. The use of cross-linked nanotubes in bucky gel results in a threefold increase of the charge transfer capability of the composite material and an increase up to ten times of the strain generated by the resulting actuators. To our knowledge, such bucky gel actuators, prepared using cross-linked super growth carbon nanotubes, outperform any other electrochemical carbon nanotube actuator presented so far.

We report an easiest synthesis strategy of a new class of synthetic dyes by coupling of functionalized pyrazolidine-3,5-dione derivatives via diazotization reaction with aromatic diamine for the azoic dyes or via dimerization reaction to synthesize the H chromophore dyes. Electron delocalization between the two coupled components has been studied using UV–vis spectroscopy, infrared, and NMR spectroscopy. In addition, the formation mechanism of such compounds has been discussed.

A novel aromatic diamine 4′-( tert -butyldimethylsiloxy)biphenyl-4-yl 3,5-diaminobenzoate (DPA) was synthesized through three steps including monoesterification, silylation and hydrogenation. DPA with different ratios was copolymerized with 4,4′-diaminodiphenyl ether (ODA) and 3,3′,4,4′-biphenyl dianhydride (BPDA) to give poly(amic acid)s which were converted into polyimides (PIs) by thermal imidization. The effect of side-chain content on the thermal stability, optical transparency and surface energies was investigated by DSC, TGA, UV–vis spectra and contact angle measurement. With the content of side-chains increasing, the PIs revealed lower thermal stability, higher optical transparency and lower surface energies. The pretilt angles of 4-pentyl-4′-cyanobiphenyl (5CB) on the PI films were measured by a crystal rotation method. For the same rubbing strength, the pretilt angles increased with the increasing of the content of side-chains. When the content of side-chains rose from 5% to 20%, the pretilt angles increased from 2.8° to 15.0° under 28.5 mm of rubbing strength. When the content of side-chains increased to 70%, 80%, 90%, and 100%, the pretilt angles was 75.0°, 82.9°, 87.0°, and 87.7°, respectively, under 28.5 mm rubbing strength.

A novel fluorinated aromatic diamine, bis[4-(4′-aminophenoxy)phenyl]-3,5-bis(trifluoromethyl)phenyl phosphine oxide, was synthesized. A series of new fluorinated polyimides containing phosphine oxide was prepared from the novel diamine with various commercially available aromatic dianhydrides. All the fluorinated polyimides show high glass transition temperatures, excellent thermal stability, and good solubility in common organic solvents.

The pervaporation separation of aqueous ethanol mixtures was carried out using a series of polyimide membranes. The soluble polyimides were prepared from 3,3′,4,4′ benzhydrol tetraacarboxylic dianhydride, BHTDA, with various diamines. The aromatic diamine structure effects on the membrane properties were investigated. The feed compositions, degree of swelling and feed solution temperature effects on the pervaporation performances of aromatic polyimide membranes were studied.

Potentiometric equilibrium studies, UV–Vis spectrophotometric and voltammetric measurements were carried out to determine the degree of binding of 4-methoxy-1,2-phenylenediamine with dicobalt(II)–BMXD complexes (BMXD is 3,6,9,17,20,23-hexaazatricyclo[23.3.1.111,15]-triaconta-1(29),11(30),12,14,25,26,27-hexaene) in the absence and presence of dioxygen. Equilibrium constants for complexes formed are reported, the results are presented in the form of distribution diagrams showing the concentrations of individual complexes as a function of p[H]. The log Ks for the oxygenation constants are: 1.74 and 2.02 for mono and dihydroxo complexes, respectively. The μ-peroxo monohydroxo complex is stabilized with an aromatic diamine substrate and the log of the association constant was found to be 4.57.

A new kind of aromatic diamine monomer containing thiazole unit, 2-amino-5-(4-aminophenyl)-thiazole (AAPT), was synthesized in three steps, starting from 4-nitroacetophenone. A novel thiazole-containing polyimide was prepared via the polycondensation of AAPT with 6FDA by one-step method. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal resistance.

A new kind of aromatic diamine monomer containing pyridine unit, 2,6-bis[4-(4-aminophenoxy)phenoxy]pyridine (BAPP), was synthesized in three steps, using hydroquinone as starting material. A novel pyridine-containing polyimide was prepared from the resulting diamine BAPP with 4,4′-oxydiphthalic anhydride (ODPA) via a conventional two-step thermal imidization method. The resulting polyimide exhibits excellent solubility, film-forming capability and high thermal resistance.

The cathode interface layer (CIL) was investigated using aromatic diamine derivatives. The organic electroluminescent (EL) device with Ag cathode and CIL of Cz-TPD (4,4′-biscarbazolyl(9)-biphenyl) showed good EL characteristics comparable to a conventional MgAg device and also an improved storage stability. X-ray reflectivity measurement suggested that the rough structure of the Cz-TPD layer lowered the electron injection barrier at the Ag interface.

We have succeeded in obtaining polarity-dependent color-variable emission from polymer electroluminescent (EL) devices with a three-layer structure. The emissive polymers used are poly(3-dodecylthiophene), poly( p -phenylenevinylene) and its derivative, and poly(9,9-dihexylfluorene). The emissive layers are separated by a layer of wide-band-gap hole-transporter, poly(N-vinylcarbazole) or an aromatic diamine, N,N′-diphenyl-N,N′-bis(3-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine. When the EL devices are operated under forward or reverse bias, they exhibit the emission from the negatively-biased polymer layer. The energy band diagram of the devices implies that the separating layer confines excitons in the negatively-biased polymer layer

Some epoxide resins with or without methoxy branches were cured with an aromatic diamine. A well defined relaxation was observed near room temperature for all cured resins with methoxy branches, independent of the epoxide-resin structure. The relaxation was denoted here as the β′-relaxation. It is suggested that the β′-relaxation can be attributed to suppression of the motion of the hydroxy ether group due to the interaction between this group and the methoxy branch. The effect of the β′-relaxation on the fracture toughness of cured epoxide resins was studied by comparing the stress intensity factor K c of a spiro-ring type epoxide resin containing a methoxy branch with that of a bisphenol A type resin. The value of K c in the former system is considerably higher above the β′-relaxation temperature than that of the latter system. This is explained by the increase in the plastic deformation region at the crack front with increase in temperature caused by the presence of the β′-relaxation.

The possibility of synthesis of polyamides of high molecular weight by the use activated bis-pentachlorophenyl esters of dicarboxylic acids in low-temperature poly-condensation has been studied. Polyamides with η sp / c =0·31−1·04 dl/g were obtained. It was shown that tertiary amines catalyse polycondensation of these esters with aliphatic diamines only. It was found that in solution in hexamethylphosphortriamide, pentachlorophenol undergoes almost no reaction with an aromatic diamine, but it forms a stable complex with an aliphatic diamine. A method of preparation of activated bis-pentachlorophenyl esters directly from dicarboxylic acids and pentachlorophenol in the presence of dicyclohexylcarbdi-imide or trifluoroacetic anhydride, is proposed.

Copolymers were synthesized by polyaddition reactions of aromatic diamine (4,4′-sulphonyl dianiline) and aliphatic diamines (1,2-diaminoethane and 1,3-diaminopropane) with N , N ′-arylenebismaleimides ( N , N ′- m -phenylene- N , N ′- p -phenylene-, and N , N ′-benzidine-). They were characterized by elemental analysis, i.r. spectra and viscosity. The thermal behaviour of copolymers was studied using Thermogravimetric Analysis (TGA). All the copolymers are stable up to 270°. Polyamides are less stable than polyaspartimides.

The basic rheokinetic patterns of curing of low molecular mass epoxy diane oligomers by 3,3′-dichloro-4,4′-diamino-diphenylmethane at the gelation stage over the temperature range 120–150°C have been studied. The formation of a macrogel is preceded by microgelation which determines the rheokinetics of curing. A relation between the rate constant of the kinetically controlled reaction and the gelation time has been found.

Diglycidyl aromatic thioethers have been synthesized by condensation of binuclear dithiophenols with epichlorohydrin, after which epoxy polymers of reticular structure prepared by reacting the thioethers with sulphur-containing diamines. The influence of the aromatic diamine structure on acoustic properties of the cured diglycidyl thioethers has been investigated, and the results compared with those obtained for the ED-20 epoxy oligomer. As a result it was found that the glass temperature Tg rises as the length and the number of sulphur-containing groups in the network polymer increases.

A solvent-resistant membrane for use in ultrafiltration processes has recently been developed by Nitro. The membrane is made from a new polyimide that can be synthesized from 1,2,3,4-butane tetracarboxylic acid and an aromatic diamine. This membrane exhibits excellent stability and high fluxes with most common organic solvents, even when tested at elevated temperatures.

Summary 1. The oxidation kinetics of T-6 fuel, inhibited with aromatic diamine — N-phenyl-N'-benzyl- p -phenylenediamine and aminophenol — p -hydroxy-Neozone- D , were studied in the presence of metallic copper at 398°K. 2. Aromatic diamine and aminophenol in the presence of copper were demonstrated to be consumed not only by reaction with free radicals, but also by oxidation with molecular oxygen and hydroperoxide. 3. Homolytic oxidation of these inhibitors on a copper surface was found to be one of the main sources of inhibitor consumption.