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Polyimides (PIs) possess excellent thermal and mechanical properties, but their poor solubility in organic solvents restricts their utility. Numerous studies have focused on improving PI solubility by weakening inter-molecular interactions within the polymer. The polyimide composed of aromatic anhydride, 6,6′-(hexafluoroisopropylidene)dipthalic anhydride and aromatic diamine, 4,4′-oxidianiline, is known to be soluble, but solubility at room temperature is very limited. In this study, a soluble polyimide copolymer, 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane (Bis-ap-af), a diamine containing hydroxyl groups, was incorporated into the above-mentioned PI via chemical and thermal imidization. Chemical imidization resulted in the acetylation of the hydroxyl groups of Bis-ap-af units, while the hydroxyls remained intact under thermal imidization conditions. The acetoxy-containing soluble polyimide copolymers displayed improved solubility in a number of organic solvents compared to the conventional PI, and the copolymer films maintained their mechanical properties and presented reduced yellowness.

Organic aromatic amines are widely used in various fields such as pharmaceuticals, pesticides, dyes, and tobacco smoke. The pollution of organic amines has become a problem that cannot be ignored, due to the extensive harmful effects on the environment and public health, which has become one of the most concerned frontier fields in the world. Identifying and microdetecting o-phenylenediamine (OPD), m-phenylenediamine (MPD), and p-phenylenediamine (PPD) using MOFs have rarely been reported. On the basis of the blue emission properties of Cu-TBDA constructed with 5,5'-((6-chloro-1,3,5-triazine-2,4-diyl)bis(azanediyl))diisophthalic acid (H4TBDA) ligand, Cu-TBDA was studied primarily to identify and detect aromatic diamine family as a multifunctional chemical sensor. Interestingly, Cu-TBDA has a very high selectivity and sensitivity to OPD and MPD with a low limit of detection (5.00 μM for OPD and 1.77 μM for MPD). Especially for OPD, Cu-TBDA has a unique switching function for it. When the concentration of OPD is less than 9.1 × 10-4 M, the fluorescence response of Cu-TBDA suspension exhibit enhanced. However, when the concentration of OPD is more than 9.1 × 10-4 M, the emission intensity displays quenching phenomenon. Therefore, Cu-TBDA as a chemical sensor not only has recognition and detection functions for organic aromatic amines but also first exhibits turn-on and -off sensing behavior toward OPD.

10,10-Bis[4-(4-aminophenoxy)-3-methylphenyl]-9(10 H)-anthrone, as a new aromatic diamine, was synthesized from 9(10 H)-anthrone by three-step procedure. Low-temperature polycondensation of this diamine with various aromatic dicarboxylic acid dichlorides produced a series of new cardo poly(ether amide)s with moderate to high inherent viscosities of 0.86–1.43 dL g−1 while the weight-average and number-average molecular weights were in the range of 48,600–59,800 and 29,800–35,600 g mol−1, respectively. All the polymers were readily soluble in polar solvents such as N, N-dimethylacetamide (DMAc), N, N-dimethylformamide, N-methyl-2-pyrrolidinone, dimethyl sulfoxide, and pyridine, and afforded transparent, flexible, and strong films upon casting from DMAc solvent. These polymers had glass transition temperatures of 254–297°C, 10% weight loss temperatures of 493–505°C, and char yields of 61–64% at 800°C in nitrogen. All polymers were amorphous and their films exhibited tensile strength of 80.7–101.4 MPa, elongation at break of 8.0–12.8%, and tensile modulus of 1.9–2.6 GPa. These polymers had low moisture uptake in the range of 2.13–4.02% and high transparency with an ultraviolet–visible absorption cutoff wavelength in the 322–375 nm range.

10,10-Bis[4-(4-aminophenoxy)-3-methylphenyl]-9(10H)-anthrone, as a novel aromatic diamine, was synthesized from anthrone by three-step process. A series of polyimides containing methyl substituents...

A new aromatic diamine, 10,10-bis[4-(4-aminophenoxy)phenyl]-9(10 H)-anthrone (BAPA) has been synthesized from anthrone via three-step procedure. Direct phosphorylation polycondensation of BAPA with various aromatic dicarboxylic acids produced a series of cardo poly(ether amide)s with inherent viscosities of 0.97–1.29 dL g−1. All the polymers were readily soluble in polar solvents such as N-methyl-2-pyrrolidone, N, N-dimethylacetamide (DMAc), and pyridine at room temperature, and afforded transparent, strong, and flexible films upon casting from DMAc solvent. The resulting poly(ether amide)s had glass transition temperatures of 254–316°C, 10% weight loss temperatures of 495–524°C, and char yields of 55–70% at 800°C in nitrogen. These polymers were amorphous and their films exhibited tensile strengths of 81.6–104.7 MPa, tensile moduli of 1.8–2.4 GPa, and elongations at break of 8–15%.

4-(4-Diphenylphosphino)phenyl-2,6-bis(4-aminophenyl)pyridine, as a novel aromatic diamine, was synthesized from 4-(diphenylphosphino)benzaldehyde and 4-nitroacetophenone through two-step, Chichibab...

Self-assembling polyimides (PIs) having diketopiperazine (DKP) components were synthesized by polycondensation of a 4-amino-l-phenylalanine (4APhe) dimer, an aromatic diamine newly designed in this study. The amino acid-derived PIs showed high thermal resistance, with a 10% weight loss temperature (Td10) of 432 °C at the maximum, and did not show any glass transition below the thermal decomposition temperature. The poly(amic acid) (PAA) precursors formed nanospheres upon reprecipitation over dimethylacetamide into water. The nanospheres were then added to solvents with different polarities and sonicated to induce deformation of the spherical forms into spiky balls, flakes, or rods. The PAA particle morphologies were retained in the PIs after the two-step imidization. Finally, the PI particles with self-assembling DKP moieties were formed, and their morphologies were fine-tuned using different mixed solvents.

A new aromatic diamine, 10,10-bis [4-(4-amino-2-pyridinoxy)phenyl]-9(10H)-anthracenone (BAPPA) was synthesized from anthrone as the starting material, and the corresponding pyridine- and anthrone-c...

A new aromatic diamine, 10,10-bis[4-(4-amino-3-trifluoromethylphenoxy)phenyl]-9( 10H)-anthrone (BATFPA), has been synthesized from anthrone via three-step procedure. Low-temperature polycondensation of BATFPA with various aromatic dicarboxylic acid chlorides produced novel fluorinated polyamides with moderate to high inherent viscosities of 0.75–1.03 dL/g while the weight-average molecular weight and number-average molecular weight were in the range of 66,000–74,000 and 37,000–41,000, respectively. Nearly, all the polymers were readily soluble in polar solvents, such as N,N-dimethyl acetamide (DMAc), N-methyl-2-pyrrolidinone, pyridine, and tetrahydrofuran, and afforded transparent, light-colored, and flexible films upon casting from DMAc solvent. These polymers had glass transition temperatures of 249–309°C, 10% weight loss temperatures of 486–517°C, and char yields of 53–61% at 800°C under nitrogen. All polymers were amorphous and their films exhibited tensile strengths of 64–86 MPa, tensile moduli of 1.8–2.2 GPa, and elongation at break of 10–18%. These polymers had dielectric constants ranging from 3.25 to 3.76 (100 Hz), low moisture uptake in the range of 0.72–1.18%, and high transparency with an ultraviolet–visible absorption cutoff wavelength in the 360–378 nm range.

Two tetradentate phenolic Schiff base ligands namely 2,2'-((1 E ,1' E )-(1,2-phenylenebis(azanyl-ylidene))bis(methanylylidene))diphenol, L1H , 2,2'-((1 E ,1' E )-(1,2-phenylenebis(azanylylidene))bis-(methanylylidene))bis(4-fluorophenol), L1F and their new nickel(II) complexes were successfully synthesized, characterized and evaluated for their in vitro anticancer activities against human colon cancer cell lines, HCT116. The compounds were characterized using FT-IR, 1 H and 13 C NMR, UV-Visible, elemental analysis and melting point. The anticancer results revealed that the parent ligands were more active than their corresponding complexes with L1F being the most potent anticancer compound with IC 50 of 2.8 mg/ml.

A new series of soluble aromatic polyamides was synthesized by low temperature solution polycondensation of novel aromatic diamine namely 3,5-bis-(4′-amino phenyl)-4-(4″-methoxy-2″-pentadecyl pheny...

A novel aromatic diamine containing 1,3,4-oxadiazole-substituted triphenylamine (TPA) was successfully synthesized and structurally characterized. Based on this, a series of three aromatic polyimid...

The epoxy resins containing imine bonding were prepared from hydroxyl substituted Schiff base monomers in two steps. At the first step, hydroxyl substituted Schiff base monomers were synthesized vi...

A new class of polyimides had been synthesized from a novel aromatic diamine, 2',7'-bis(4-aminophenoxy)-spiro(4,5-diazafluoren-9,9'-xanthene). Polyimides were prepared by two-stage polycondensation of diamine monomer with various aromatic dianhydride. These polymers showed good thermal stability, solubility and optical transparency. These polymers showed good thermal stability, solubility and optical transparency. Except 6a, all polyimides were dissolved in aprotic polar solvents at room temperature. The glass transition temperatures (Tg) of the poly(ether imide)s were determined to be 338���423 ��C and 345���428 ��C by dynamic mechanical thermal analyses (DMA) and differential scanning calorimeter (DSC), respectively. Decomposition temperature for 10% weight loss all of these poly(ether imide)s above 560 ��C in both nitrogen and air atmospheres. Normalized transparencies in the visible region (400���780 nm) were recorded between 67% and 83%. The dielectric constants of polyimide film were recorded in the range of 2.56���3.12 at 1 KHz.

A new aromatic diamine, 4-(4-trifluoromethyl)phenyl-2,6-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]pyridine, was synthesized by a modified Chichibabin reaction of 4-(4-nitro-2-trifluoro...

This work provides an unprecedented example of a chiral aromatic amine used to activate α,β-unsaturated ketones in asymmetric aminocatalysis. Chiral aromatic diamine VII has been efficiently employed, as a proof of concept, in the Michael addition reaction between benzylideneacetones (1a-f) and coumarins (2a-d). The reaction gives rise to warfarin derivatives 3 with promising results using this family of catalysts for the first time. The additional studies performed supported the bifunctional mode of activation of the chiral catalyst VII and the covalent nature of the interactions between the catalyst VII and benzylideneacetones 1., This work was supported by a 2018 Leonardo Grant for Researchers and Cultural Creators, BBVA Foundation. The authors also thank Ministerio de Economía, Industria y Competitividad (MINECO-FEDER CTQ2016-75816-C2-1-P and CTQ2017-88091-P), Universidad de Zaragoza (JIUZ-2017-CIE-05) and Gobierno de Aragón-Fondo Social Europeo (Research Group E07_17R) for financial support of their research. We acknowledge support of the publication fee by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI).

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.

4-(4-Trifluoromethylphenyl)-2,6-bis[4-(4-amino-2-trifluoromethylphenoxy)phenyl]pyridine (9FPBAPP), as a new aromatic diamine, was prepared by a modified Chichibabin reaction of 4-(4-nitro-2-trifluoromethylphenoxy)acetophenone with 4-triflouromethylbenzaldehyde, followed by a catalytic reduction. A series of fluorinated poly(ether imide)s containing pyridine and/or phenylphosphine oxide moieties were prepared from bis(3-aminophenyl)phenylphosphine oxide (BAPPO), 2,2′-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA), and 9FPBAPP via a conventional two-step thermal imidization procedure with various mole ratios of BAPPO and 9FPBAPP. All the polymers were amorphous and soluble in common organic solvents such as N, N-dimethylacetamide and N-methyl-2-pyrrolidone and had Tg’s of 277–285°C, 5% weight loss temperature of 521–550°C in nitrogen. Furthermore, high char yields and good limited oxygen index values indicated that these polymers exhibited good thermal stability and flame-retardant property. Tough and flexible polymer films also had good mechanical properties with tensile strengths of 75–99 MPa, tensile moduli of 1.1–1.6 GPa, and elongations at break of 12%–24% and low dielectric constants of 2.81–3.53 (1 MHz), as well as high optical transparency with the ultraviolet cutoff wavelength in the range of 350–384 nm.

Achiral glycolic acid and chelating aromatic diamine ligands were employed at room temperature to prepare five 1D copper(II) coordination polymers which were structurally characterized. The polymers ∞1{[Cu(HG)(dipyam)](HG)} (1) (dipyam = 2,2′-dipyridylamine) and ∞1[Cu(HG)(ClO4)(NN)] (NN = 2,2′-bipyridine (2), NN = 1,10-phenanthroline (3)) adopt homochiral helical structures in the crystal state and undergo spontaneous chiral resolution in the solid state. On the other hand, the polymers containing bidepronated glycolato ligand G, ∞1{[Cu(G)(dipyam)]·H2O} (1a), obtained from a solution of 1 in MeOH/iPrOH and ∞1{[Cu2(μ-G)(ClO4)(H2O)(dipyam)2](ClO4)(H2O)2} (4b) are achirals. Crystals of 4b have been obtained together with crystals of the molecular complex [Cu(HG)(H2O)(dipyam)](ClO4) (4a). Analysis by Hirshfeld surface generation and two-dimensional fingerprinting was carried out to study the nature of the interactions and their contributions towards the crystal packing.

A partially biobased aromatic diamine – namely, 1,1-bis(4-aminophenyl)-3-pentadecylcyclohexane (BAC15) – was synthesized starting from cardanol. A series of polyimides were synthesized by one-step high-temperature solution polycondensation of BAC15 with aromatic dianhydrides. Copolyimides were also synthesized by polycondensation of various compositions of BAC15 and 4,4′-oxydianiline with 3,3′,4,4′-biphenyl tetracarboxylic dianhydride. The inherent viscosities and number-average molecular weights of (co)polyimides were in the range of 0·33–1·4 dl/g and 14 700–31 900 g/mol, respectively, indicating formation of reasonably high-molecular-weight polymers. Polyimides were soluble in common organic solvents such as chloroform, dichloromethane and tetrahydrofuran and could be cast into transparent, flexible and tough films from their solutions in chloroform. (Co)Polyimides exhibited glass transition temperatures (T g) in the range of 161–254°C. The lowering of T g could be attributed to the presence of flexible pentadecyl chains, which act as ‘packing-disruptive’ groups. The temperature at 10% weight loss (T 10) of (co)polyimides was in the range of 490–515°C, demonstrating their good thermal stability. The virtue of solubility and the large gap between T g and T 10 offers (co)polyimides opportunities of both solution and melt processability. Copolyimides containing pendent pentadecyl chains exhibited pretilt angles in the range of 2·51–2·75°, indicating their potential application as an alignment layer in liquid crystal display (LCD) devices.

A novel aromatic diamine monomer (4,4′-(dibenzofuran-2,8-diyl) dianiline (DFPDA)) derived from the rigid planar dibenzofuran was synthesized through Suzuki coupling reaction. The aromatic polyimide...

Based on the aromatic diamine monomer containing di-tert-butylbenzene and methyl groups, this work proposes its polymerization with four different dicarboxylic acids. The prepared polyamides (PA 3a–3d) were characterized by GPC, FTIR, 1H NMR, mechanical, thermal, optical and gas separated techniques. They exhibited high solubility and good optical transparency. Their optical transmittance at 450 nm wavelength was in the range of 81.4%–86.8%, and the cutoff wavelength was in the range of 327–352 nm. The membranes also had good mechanical properties with tensile strength of 79.7–91.4 MPa, elongations at breaks of 9.0–10.9% and initial modulus of 1.5–1.9 GPa. Meanwhile, these membranes possessed good thermal properties with glass transition temperature (Tg) values of 226–246 °C. The permeability of CH4, N2, and CO2 for these membranes was tested by constant pressure-variable volume method. The PA 3d containing tert-butyl moiety in the diacid units exhibited highest permeability (PCO2 = 31.4 and PN2 = 1.9) whereas PA 3c containing hexafluoroisopropylidene moiety exhibited highest selectivity (CO2/CH4 = 22.2).

Aromatic diamines containing hexafluoroisopropylidene and ester moiety were synthesized from 4,4'-hexafluoroisopropylidene diphenol and nitrobenzoyl chloride. The reaction of aromatic diamines with hexafluoroisopropylidene phthalicdianhydride (6FDA) or pyromellitic dianhydride (PMDA) gave four kinds of poly(amic acid)s. Their inherent viscosities ranged from 0.196 to 0.346 dL/g. Poly(amic acid)s were converted to polyimides by thermal imidization. The glass transition temperatures (Tg) of polyimides were between 241 and 289 ℃. The 5% weight loss temperatures were recorded in the range of 430~492 ℃. The tensile strength of polyimide films were measured as 29.84~64.38 MPa.

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.

2,4-Toluene diisocyanate is substituted with isophorone diisocyanate during the synthesis of polybutadiene urethane urea. The obtained polydiene urethane urea is shown to be superior to the physicomechanical and rheological properties of the traditional material synthesized with the use of 2,4-toluene diisocyanate. It is established that polybutadiene urethane urea is more than twice as good as steel adhesion to polydiene urethane epoxy compounds.

Based on a mixture of 2,4 and 2,6-tolylene diisocyanate of a grade Desmodur T-80 and polyesters P6-BA and PDA-800. Reactive isocyanate-containing prepolymers for polyurethane composite materials were synthesized. On the basis of alkanolamine Lapromol A-294, polyesters of various structures and an aromatic diamine Curalon M curing systems for polyurethane composites were developed. The effect of a ratio of isocyanate-, hydroxyl-, and amine-containing components on the properties of the prepolymers and curing systems was investigated. Polyurethane composites were produced and their performance characteristics were studied.

A series of polyimide aerogels with intrinsically atomic-oxygen-resistant features have been synthesized. For this purpose, 3,3',4,4'-biphenyltetracarboxylic dianhydride (s-BPDA) was copolymerized with 2,2'-dimethylbenzidine (DMBZ) and a polyhedral oligomeric silsesquioxane (POSS)-containing aromatic diamine, N-[(heptaisobutylPOSS)propyl]-3,5-diaminobenzamide (DA-POSS), with octa(aminophenyl)silsesquioxane (OAPS) as the crosslinker via sol-gel procedures followed by supercritical carbon dioxide (scCO(2)) drying treatments.

A kind of Polyimide films (PI films) containing biphenyl and bis-benzimidazole rings were prepared from the its precursor Polyamic acid (PAA) solution synthesized by aromatic diamine containing biphenyl and bis-benzimidazole rings with different commercial aromatic dianhydrides. The PI films exhibited excellent hydrophobicity with the contact angle of higher than 90o and the hydroscopicity are lower than 1%. The PI films also have great dielectric properties of the dielectric constant ranges from 2.10 to 2.94 under the voltage frequency within 1 to 106HZ.

Four wholly aromatic Poly (amide-sulfonamide) s (PASAs) were synthesized by the solution polycondensation from m-chlorosulfonyl benzoyl chloride and aromatic diamines in tetramethylene sulfone and substituted 2-Piucoline as the acid acceptor. The chemical structures of PASAs were characterized by FTIR, 1HNMR. Thermal properties of PASAs were investigated by TGA.

In the present study, benzocyclobutene (BCB) was incorporated into the benzoxazine (BOZ) monomers. BCB-functionalized BOZ monomers were synthesized by the reaction of 4-hydroxybenzocyclobutene, aromatic diamine, and paraformaldehyde in dioxane under reflux. The structure of the monomers was characterized by Fourier transform infrared spectroscopy (FTIR) and proton and carbon nuclear magnetic resonance spectroscopies. The monomers possess two kinds of ring-opening polymerizable functional groups, BCB and BOZ. Differential scanning calorimetry and FTIR were used to study the polymerization behavior of the monomers. Dynamic mechanical analysis demonstrates that the related polymers show high storage moduli maintained in a wide range of temperature up to 300°C and high glass transition temperature at about 330°C. The incorporation of BCB improved the thermal stability and mechanical property of the monomer.

Traditional polyetherimides (PEIs) are commonly synthesized from an aromatic diamine and an aromatic dianhydride (e.g., 3,4′-oxidianiline (ODA) and 4,4′-oxidiphtalic anhydride (ODPA)) leading to the imide linkage and outstanding chemical, thermal and mechanical properties yet lacking any self-healing functionality. In this work, we have replaced the traditional aromatic diamine by a branched aliphatic fatty dimer diamine (DD1). This led to a whole family of self-healing polymers not containing reversible chemical bonds, capable of healing at (near) room temperature yet maintaining very high elastomeric-like mechanical properties (up to 6 MPa stress and 570% strain at break). In this work, we present the effect of the DD1/ODPA ratio on the general performance and healing behavior of a room temperature healing polyetherimide. A dedicatedanalysis suggests that healing proceeds in three steps: (i) an initial adhesive step leading to the formation of a relatively weak interface; (ii) a second step at long healing times leading to the formation of an interphase with different properties than the bulk material and (iii) disappearance of the damaged zone leading to full healing. We argue that the fast interfacial adhesive step is due to van der Waals interactions of long dangling alkyl chains followed by an interphase ormation due to polymer chain interdiffusion. An increase in DD1/ODPA ratio leads to an increase in the healing kinetics and displacement shift of the firsthealing step toward lower temperatures. An excess of DD1 leads to the cross-linking of the polymer thereby restricting the necessary mobility for the interphase formation and limiting the self-healing behavior. The results here presented offer a new route for the development of room temperature self-healing thermoplastic elastomers with improved mechanical properties usingfatty dimer diamines.

4,4′-(1,3-Phenylenebis(oxy))dianiline 1 is an aromatic diamine compound and has been very less utilized in the organic synthesis. Different diimines and diamides were synthesized by reacting compound 1 with aromatic and heterocyclic compounds having different functionalities. These longer electron rich spacer molecules were synthesized to utilize them in the near future in making macrocycles of different sizes and functionalities. A hydrazide was also prepared from a diamide spacer molecule containing ester group. A diamide prepared containing nibrobenzene moiety was further reduced to amine to obtain longer spacer diamine molecule than the starting molecule 1.

Copoly(ether-imide)s formed by the reaction of an aromatic dianhydride (BPDA), an aromatic diamine (ODA), and various aliphatic diamines (PEO-2000, PPO-2000, RT-1000, pTHF-1700, and pTHF-350) have ...

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.

An aromatic diamine monomer, 1H,1H-perfluorooctyl 3,5-diaminobenzoate (PFD), was synthesized in three steps, which was used to prepare the polyimides containing pendant perfluoroalkyl chains via th...

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.

The novel high-temperature resistant shape memory (SM) materials which were prepared based on diglycidylether of bisphenol A (DGEBA) epoxy resin with a chain-extended aromatic diamine containing phthalide cardo structure (BAPP) as curing agent. The influence of deformation temperature and loading rate on the deformability, and the dependence of shape recovery ratio (R r) and shape fixity ratio (R f) on the fixed deformation temperature, imposed deformation load, shape fixity cooling rate and number of cycles were investigated by dynamic mechanical analyzer (DMA) in comparison with these of the common aromatic amine-cured epoxy systems. The deformability, R r and R f could be improved markedly by changing the SM programming conditions. The results demonstrate the incorporation of phthalide groups plays an important role on the improvement of SM performance of epoxy networks.

A series of new highly efficient chiral aliphatic–aromatic diamine catalysts have been designed and successfully applied to the asymmetric Michael addition of cyclohexanone with nitroolefins under solvent-free conditions without any acidic additives. The desired adducts were obtained in high yields with excellent enantio- and diastereoselectivities of syn products (up to >99% ee, >99:1 dr). Chirality 2010. © 2010 Wiley-Liss, Inc

Two novel aromatic diamine monomers, Bis-4,4′[(4-aminophenyl-2,2′-isopropylidene phenyloxy)] diphenylsulfone and Bis-4,4′[(4-aminophenyl-2,2′-isopropylidene phenyloxy)] benzophenone were synthesized and characterized by IR and 1H-NMR. A series of processable polyimides were prepared by polycondensation of diamines with aromatic dianhydrides. The polyimides were characterized by infrared, 1H-NMR, X-ray diffraction, thermogravimetric analysis, differential scanning calorimetry, gel-permeation chromatography, solution viscosity and solubility. Polyimides were soluble in polar approtic solvents and increases in solubility in common organic solvents were observed due to the presence of flexible groups and methyl groups in the chain backbone. The polyimides exhibited good thermal stability, and the temperature at which 10% weight loss occurred ranged from 378 to 465 °C in nitrogen. X-ray diffraction measurements revealed that the polyimides were amorphous.

Three kinds of aromatic diamines (DETDA,tBu-TDA,CPA) as chain extenders and novel polypropylene glycols (designated PPGs) were used for polyurethaneurea reaction injection molding (designated RIM) elastomer. The morphology and physical properties of each polyurethaneurea RIM elastomer were studied by using TEM, SEM, dynamic mechanical thermal analysis. The polyurethaneurea RIM elastomer by using CPA as a chain extender showed superior heat sag data as compared with DETDA and tBu-TDA .As novel PPGs contain an extremely smaller amount of by-products (monools), the actual functionalities of novel PPGs are higher than that of conventional ones. Polyurethaneurea RIM elastomers by using novel PPGs showed good physical properties and productivity. Especially, heat resistance property from 150 °C to 230 °C was improved by the increase of crosslinking density of polyurethaneurea RIM elastomers. It was also revealed that the increase in molecular weight of novel PPGs and a rise of the post cure temperature accelerate the phase separation of polyurethaneurea RIM elastomers. The transformation of morphology was observed.

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.

Four nitrogen-containing organic compounds [1,5,7-triazabicyclo(4,4,0)dec-5-ene, 4-(N,N-dimethylamino)pyridine, N-methylimidazole, and l-proline] have been tested as organocatalysts for the reaction of dimethyl carbonate with an aromatic diamine, 2,4-diaminotoluene (DAT). Although, generally, N-methylation was the predominant process, variable proportions of N-carbamoylation were also observed. Reaction kinetics indicates that N-methylation and N-carbamoylation are independent and parallel processes. DAT conversion increases as the temperature increased over the range of 105−125 °C. Besides the nature of the organocatalyst, the ratio between N-methylation/N-carbamoylation was influenced by the DAT-to-DMC ratio: higher DAT proportions increased the DAT conversion and favored N-carbamoylation. 4-(N,N-dimethylamine)pyridine was determined to be the most active organocatalyst of the series and, under certain conditions, can lead to selective N-methylation with high conversion.

PMR-15 has long been the leading resin system for high performance composite applications requiring long-term use temperatures up to 300°C. A mixture of carboxylic esters and acids, aromatic diamine and norbornyl end caps capable of crosslinking by a reverse Diels—Alder mechanism in methanol is pre-pregged into cloth and under careful processing conditions produces high quality composite parts. Some problems with handling and processing remain in this commercial system and in an attempt to overcome these problems we have synthesized a series of fully cyclized PMR type prepolymers under aqueous imidization conditions. Their solubility and cure behavior have been determined with a view to producing resins that will form good quality, high performance composites. While resins with these characteristics have been obtained, the best of them utilize significant proportions of relatively expensive co-monomers. Almost all of the materials presented in this study have very high temperature stability and high glass transition temperatures, although no one system out performs PMR-15 on a monomer cost basis, the advantages of water as the synthesis solvent includes both its low cost and low toxicity and its ability to fully react the monomers to cyclic imide structures.

A new aromatic diamine monomer containing both pyridine and fluorine, 2,6-bis(4-amino-2-trifluoromethylphenoxy-4 '-benzoyl)pyridine (BAFP), was successively synthesized by the nucleophilic substitution reaction of 2,6-bis(4,4'-dihydroxybenzoyl)pyridine with 2-chloro-5-nitro-trifluoromethylbenzene in the presence of k2CO 3 in N, N-dimethylacetamide, and followed by reduction with SnCl2 and HCl in ethanol. The polycondensation of BAFP with four aromatic dianhydrides afforded a series of novel aromatic polyimides containing both pyridine and fluorine. The reaction was conducted by the one-step thermal imidization method. The resulting polyimides were characterized for inherent viscosity, solubility, and thermo-oxidative stability. The polyimides exhibited excellent solubility in various solvents such as N-methyl-2-pyrrolidone (NMP), N, N-dimethylacetamide (DMAc), dimethyl sulfoxide (DMSO) and chloroform. The glass-transition temperatures ( Tg) were in the range of 206—227°C. The polyimides displayed good thermal stability, e.g. the temperatures at the 5% weight loss range were at 487—543°C in nitrogen and 463—521°C in air, respectively. Wide-angle X-ray diffraction measurements revealed that the polyimides were predominantly amorphous.

Preparations of Aromatic Diamine Monomers and Copolyamides Containing Phosphorylcholine Moiety and the Biocompatibility of Copolyamides

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.