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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.

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 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.

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.

Herein, we present a selective synthesis of 2-substituted and 1,2-disubstituted benzimidazoles by acceptorless dehydrogenative coupling of aromatic diamine with primary alcohols. The reaction is catalyzed by a phosphine-free tridentate NNS ligand-derived manganese(I) complex.

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.

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.

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.

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.

Polyamides with chiral environment were obtained from aromatic diamine, 1,3-phenylenediamine (1,3-PDA) or 1,4- phenylenediamine (1,4-PDA), and N-α-benzoyl-L-glutamic acid (Benzoyl-L-Glu). The optical rotation ([α]D) for 1,3- PDA-Benzoyl-L-Glu was determined to be 3.7 deg cm2 g–1, while that for 1,4-PDA-Benzoyl-L-Glu to be 9.7 deg cm2 g–1. 1,3-PDA-Benzoyl-L-Glu showed adsorption selectivity toward D-Glu and its adsorption selectivity was determined to be 1.68. Contrary to this, 1,4-PDA-Benzoyl-L-Glu showed adsorption selectivity toward L-Glu and the adsorption selectivity toward L-Glu was determined to be 1.33. From those results, those two types of chiral polyamide are expected to applicable to chiral separation or chiral recognition.

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.

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.

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

The tether-directed method was firstly applied to the biscyclopropanation of [60]fullerene via the addition–elimination reaction of bis(sulfonium ylide)s to give bis(formylmethano)[60]fullerenes with satisfactory regio- and stereoselectivity. The equatorial-bisadduct thus obtained was used for the polycondensation with an aromatic diamine to afford the corresponding pearl-necklace polyimine with satisfactorily high degree of polymerization.

Zinc (II) diporphyrin systems, characterised by the presence of flexible oligooxaethylene spacers of different lengths, have been synthesised and the binding properties toward a series of aliphatic and aromatic diamine derivatives characterised by different structural and coordination properties, investigated. The results obtained, compared to that for a rigid diporphyrin cleft, point out that the observed degree of selectivity is dependent both on the length of the spacer and on the nature of the nitrogen ligands.

New High Pressure Polymerization and Simultaneous Processing for Polyaminoimide from Aromatic Diamine and Bismaleimide

4-Chloro-1,2-phenylenediamine (4-Cl-o-PDA) is an aromatic diamine used as a precursor for manufacture of hair dyes and dyes of other purposes. 4-Cl-o-PDA has been found to be photomutagenic in bacteria when concurrently exposed to simulated sunlight irradiation. Irradiation of 4-Cl-o-PDA by either outdoor sunlight or indoor lamp, one main photoproduct appeared and it was found to be 2,3-diamino-7-chlorophenazine, a dimerized product through the excited state reaction of 4-Cl-o-PDA in the presence of oxygen. The isolated yield of 13% for 2,3-diamino-7-chlorophenazine is far better than the oxidation reaction of 4-Cl-o-PDA by H2O2 and may therefore be used as a synthetic method. The half live of transformation for 4-Cl-o-PDA in water (100 μM) is 39 min when exposed to outdoor sunlight. The photomutagenicity of 4-Cl-o-PDA and its photoproduct were tested in Salmonella typhimurium TA102. Under the same conditions, both compounds are photomutagenic. In addition, 2,3-diamino-7-chlorophenazine is both phototoxic and mutagenic.

The title compound, C(33)H(24)N(4), was prepared by the reaction of a bifunctional aromatic diamine (4,4'-diamino-diphenyl-methane) and an aldehyde (quinoline-2-carboxaldhyde). The mol-ecule consists of two nearly planar (or r.m.s. deviation = 0.017 Å) 4-methyl-N-[(E)-quinolin-2-yl-methyl-idene]aniline moieties, which are linked by the methyl-ene group. The angle between the mean planes of the two benzene rings connected to the methyl-ene group is 77.86 (11)°.

Bacterial mutagenicity of five hair dye intermediates was examined after oxidation by hydrogen peroxide under alkaline condition (pH>10), using Salmonella typhimurium TA98 as the tester strain. Hair dye intermediates tested were p-phenylenediamine, p-toluylenediamine, o-nitro-p-phenylenediamine, and 2, 4-diaminoanisole. In the case of oxidation of p-phenylenediamine, m-phenylenediamine, or 2, 4-diaminoanisole, the mutagenic activity of aromatic diamine varied with the amine concentration in the reaction mixture. Similar effect was also observed with hydrogen peroxide. A lower mutagenic activity was observed when a lower concentration of amine or hydrogen peroxide was employed. Such a concentration effect was not significant in the oxidation of p-toluylenediamine and o-nitro-p-phenylenediamine. In the case of oxidation of amine mixtures, the derived mutagenic activity varied markedly with the molar ratio or the concentration of constituent amines. Therefore, the mutagenic activity of oxidative hair dyes might depend not only on the kind of hair dye intermediates in hair dye preparations, but also on their concentrations.

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.

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.

Aromatic polyamide-imides containing different main chains were prepared by the reaction of 4-chloroformyl phthalic anhydride with various aromatic diamines, and their thermal stability was studied by thermogravimetric analysis. The aromatic polyamide-imides are less thermally stable than aromatic polypyromellitimides, but are more stable than wholly aromatic polyamides. The thermal stability of aromatic polyamide-imides decreases in the following order of aromatic diamine components.