Showing papers on "Phthalonitrile published in 2014"

A novel high-temperature naphthyl-based phthalonitrile polymer: synthesis and properties

Abstract: A novel naphthyl-based phthalonitrile monomer, 1,6-bis(3,4-dicyanophenoxy) naphthalene (1,6-BDCN), was prepared, and the phthalonitrile resin was cured with 4,4′-diaminodiphenyl ether (ODA) via two steps, namely, preparation of prepolymer and postcuring prepolymer at elevated temperatures. The 1,6-BDCN polymer might form triazine and phthalocyanine rings as demonstrated by FTIR spectra. The prepolymer shows fine solubility in organic solvents. The 1,6-BDCN polymer exhibits excellent structural integrity and superior thermal stability as indicated by thermogravimetric analysis (TGA). Dynamic mechanical analysis (DMA) revealed that the phthalonitrile resin has a high storage modulus and glass transition temperature (Tg). The water uptake is about 3% by weight after submersion in boiling water for 50 hours. The influence of curing processes on thermal stability and flame retardancy was also explored.

Synthetic approaches to asymmetric phthalocyanines and their analogues

Abstract: This review summarizes synthetic strategies for the preparation of asymmetric phthalocyanines and their analogues. Cross-condensation between two phthalonitrile components, cross- condensation between one phthalonitrile and one non-nitrile component, targeted synthesis of AABB-type compounds, the subphthalocyanine ring-expansion method, as well as post- modification approaches on pre-formed symmetric and asymmetric systems, are discussed. Methodologies for targeted preparation of specific types of asymmetric phthalocyanines and their analogues are also briefly overviewed.

Synthesis and properties of a novel high-temperature diphenyl sulfone-based phthalonitrile polymer

Abstract: A novel high-temperature diphenyl sulfone-based phthalonitrile polymer is prepared from bis-[4-(3,4-dicyanophenoxy)phenyl]sulfone (BDS) monomer synthesized with high yield by a simple nucleophilic displacement of a nitro-substituent from 4-nitrophthalonitrile (NPN). The structure of BDS polymer is investigated by Fourier transform infrared spectroscopy and wide-angle X-ray diffraction. Curing behavior of BDS monomer with 1,3-bis(4-aminophenoxy)benzene (APB) is recorded by differential scanning calorimetry. The properties of BDS polymer are evaluated by thermogravimetric analysis, dynamic mechanical analysis, and tensile test. The results reveal that the BDS polymer exhibits excellent thermal and thermo-oxidative stabilities, high glass temperature (Tg = 337°C), and outstanding mechanical properties (Young’s modulus: 4.02 GPa and tensile strength: 64.16 MPa). Additionally, the BDS polymer exhibits high flame retardance and low water uptake.

Synthesis and properties of poly(aryl ether ketone)-based phthalonitrile resins

Abstract: A series of poly(aryl ether ketone) oligomers containing phthalonitrile were synthesized by a direct solution polycondensation, and characterized by fourier transform infrared spectroscopy and hydrogen nuclear magnetic resonance. Differential scanning calorimetry results showed the oligomers had low melting points and large processing windows (103–124°C) in the presence of bis[4-(4-aminophenoxy)phenyl]sulfone. The uncured synthesized oligomers had good solubility while the cured samples became insoluble in common organic solvents. Isothermal rheometric analysis showed the rate of phthalonitrile polymerization could be controlled easily by varying concentration of curing additive and curing temperature, which indicated that the oligomers possessed good processability. Gel content measurements demonstrated that the cured oligomers had high crosslinking density with the significantly high gel content over 90.1%. Dynamic mechanical analysis indicated the oligomeric phthalonitrile resins according to our curing procedure possessed good thermal mechanical properties. Thermogravimetric analysis of cured resins showed the highest temperature for 5% weight loss reached 515 and 516°C under nitrogen and air, respectively, and the char yield was over 67% at 800°C, revealing that the phthalonitrile resins possessed excellent thermal and thermo-oxidative stability. This kind of the oligomeric phthalonitrile resins may be used as a good candidate for high-performance polymeric materials. POLYM. ENG. SCI., 54:1695–1703, 2014. © 2013 Society of Plastics Engineers

7-Oxy-3-(3,4,5-trimethoxyphenyl)coumarin substituted phthalonitrile derivatives as fluorescent sensors for detection of Fe3+ ions: Experimental and theoretical study

Abstract: The novel 7-hydroxy-3-(3,4,5-trimethoxyphenyl)coumarin ( 1 ) has been synthesized via Perkin reaction and its phthalonitrile derivatives ( 2 , 3 , 4 and 5 ) have also been prepared from the reaction of this coumarin ( 1 ) with 3-nitrophthalonitrile, 4-nitrophthalonitrile or 4,5-dichlorophthalonitrile compounds for the first time in this study. The newly synthesized compounds have been fully characterized by 1 H NMR, MALDI-TOF, FT-IR, UV–vis and fluorescence spectral data as well as elemental analysis. The exact structure of the coumarin substituted phthalonitrile derivatives ( 2 , 3 and 5 ) have also been determined using X-ray diffraction. The electronic absorption and fluorescence properties of these new compounds have been studied in different solvents. The chemosensor behaviors of these compounds to metal ions have also been examined by fluorescence spectroscopy and these compounds exhibited as fluorescence chemosensor for the determination of Fe 3+ ions in solution. Fe 3+ complex structures of mono-coumarin ring substituted derivatives ( 1–4 ) have been investigated by using density functional theory computations.

Self‐catalyzed silicon‐containing phthalonitrile resins with low melting point, excellent solubility and thermal stability

Abstract: A series of silicon-containing self-catalyzed phthalonitrile derivatives (SiPNs) have been successfully synthesized from reaction of 4-(4-aminophenoxy)phthalonitrile (APN) with corresponding chlorosilanes. The chemical structures of the SiPNs were confirmed by spectroscopic techniques. The introduction of silicon-containing unit into the phthalonitrile structure has dramatically decreased the melting point from 143°C for APN to 40–60°C for the new SiPNs, which also exhibit improved solubility and are soluble in many common solvents. Differential scanning calorimetry analysis showed that they possess the self-catalyzed behavior with the temperature of exothermic peak due to the self-catalyzed reaction between 255 and 281°C. The cured SiPNs exhibit excellent thermal stability with glass transition temperature above 450°C, the temperature of 5% weight loss in range of 535–570°C under nitrogen, and 543–562°C under air. Their char yields at 1000°C are in the range of 80.2–82.6% in nitrogen, and 10.1–12.5% in air, respectively. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40919.

Synthesis and characterization of phthalonitrile resins from ortho-linked aromatic and heterocyclic monomers

Abstract: A Badshah, M R Kessler, Z Heng, A Hasan: Synthesis and Characterization of Phthalonitrile Resins from Ortho-Linked Aromatic and Heterocyclic Monomers, Polymer International, 2014, 63, 465-469 DOI: 101002/pi4527

Synthesis and properties of polyimides derived from a new phthalonitrile-containing diamine with high polyaddition reactivity

Abstract: A new phthalonitrile-containing diamine, 1,3-bis(4-aminophenoxy)-5-(3,4-dicyanophenoxy)benzene (CN-APB), was readily synthesized via a three-step route. The key intermediate, 3,5-bis(4-nitrophenoxy)-phenol (compound 1), was synthesized by carefully controlling the molar ratio of phloroglucin to 1-chloro-4-nitrobenzene, which is a key to minimize the production of undesirable byproducts. FTIR and 1H NMR techniques were used to fully verify the proposed structure of this new phthalonitrile-containing diamine. The polyimides were prepared from such new diamine and commercial dianhydrides by low-temperature polyaddition and subsequent chemical imidization. The inherent viscosities of all polymers were over 0.50 dL/g due to the relatively high reactivity of this new diamine. The organosolubility and thermal properties of these polymers were investigated.

The synthesis and characterization of nonperipherally tetra terminal alkynyl substituted phthalocyanines and glycoconjugation via the click reaction

Abstract: In order to obtain nonperipherally tetra terminal alkynyl substituted phthalocyanines (Pcs), new 3-pent-4-ynyloxy phthalonitrile (3) was prepared by the nucleophilic displacement reaction of 3-nitrophthalonitrile (1) and 4-pentyn-1-ol (2) and then cyclotetramerization was attained in the presence of zinc acetate, cobalt acetate, and/or DBU in n-pentanol without protection/deprotection. For the first time, the glycoconjugation of the nonperipherally tetra terminal alkynyl substituted zinc phthalocyanine (ZnPc) (6) can be easily achieved via the click reaction in a high yield. The electronic absorption spectrum of the glucopyranosyl substituted ZnPc (10) derivative showed a red-shifted Q band at 751 nm in dichloromethane due to the protonation of the meso nitrogens of the Pc macrocycle. Deacylation yielded ZnPc (11) bearing glucose substituents at nonperipheral positions with an improved water-solubility and non-aggregation in DMSO. The chemical structures of the new compounds were characterized by 1H NMR, 13C NMR, FT-IR, UV-Vis, mass spectrometry and elemental analysis. Moreover, the phthalonitrile compound was characterized using X-ray.

TD-DFT calculations and MCD spectroscopy of porphyrin and phthalocyanine analogues: rational design of photosensitizers for PDT and NIR region sensor applications

Abstract: Geometry optimizations and TD-DFT calculations have been carried out on series of fused-ring-expanded phthalonitriles, phthalocyanines, and aza-dipyrromethene boron difluoride (aza-BODIPY) dyes and trends in their optical and redox properties have been analyzed. The potential utility of fused-ring-expanded phthalocyanine and aza-BODIPY analogues for photodynamic therapy and near infrared region sensor applications is assessed on this basis. Recent attempts to prepare fused-ring-expanded aza-BODIPY analogues with benzene, pyrazine, and naphthalene rings have demonstrated that the properties of aza-BODIPYs vary markedly when different fused ring systems are added to the b-carbons of the pyrrole rings. A comparison of the TD-DFT calculations demonstrates that, as has previously been postulated, trends in the optical spectra, redox properties, and electronic structures of aza-BODIPYs follow those observed for the phthalonitrile precursors and the analogous phthalocyanines despite the absence of a fully conjugated macrocyclic perimeter that obeys Huckel's rule.

Phthalonitrile-functional multiple arylene ether nitrile-containing phthalazinone moiety: facile synthesis, curing, and properties

Abstract: This article discloses a series of processable multiple phthalazinone-based ether nitriles with various contents of phthalonitrile ends (compounds 4a–4e) and compares the cyclization feasibility of...