Phthalazinone Ether Ketone Research Articles

Soluble and crosslinkable poly(phthalazinone ether ketone)s with pendent terminal ethynyl groups: synthesis, characterization and click modification

AbstractNew poly(phthalazinone ether ketone)s (PPEKs) with pendent terminal ethynyl groups were synthesized by the aromatic nucleophilic substitution (SNAr) polycondensation reaction of a new bisphenol monomer, 2‐(3‐ethynylphenyl)hydroquinone, with 4‐(4′‐hydroxyphenyl)phthalazin‐1(2H)‐one and 4,4′‐bis(4‐fluorophenyl) ketone, followed by click modification reaction with 1‐azidopyrene. Fourier transform infrared and NMR spectral data of the model compound indicated that the terminal ethynyl groups were stable in SNAr reaction conditions, thus allowing the synthesis of the desired polymers. The PPEKs obtained with glass transition temperature (Tg) in the range 152–245 °C were amorphous, characterized by wide‐angle X‐ray diffraction, and dissolved in organic solvent to cast into transparent and flexible films. Differential scanning calorimetry results indicated that the curing reaction of the terminal ethynyl groups of the copolymers took place upon heating to 250 °C. The Tg of cured PPEKs was increased to about 260 °C. They also exhibited excellent thermal stability with 5% weight loss temperatures ranging from 448 to 527 °C in various atmospheres. The PPEKs with pendent terminal ethynyl groups were subsequently functionalized with pyrene through click reaction. A dilute chloroform solution displayed a red‐shifted emission profile. © 2014 Society of Chemical Industry

Improvement of interfacial properties of carbon fiber‐reinforced poly(phthalazinone ether ketone) composites by introducing carbon nanotube to the interphase

This article aims to improve interfacial properties of carbon fiber‐reinforced poly(phthalazinone ether ketone) (PPEK) composites by means of preparing carbon nanotube (CNT)/carbon fiber hybrid fiber. XPS was used to characterize the chemical structure of unsized carbon fiber and SEM was used to observe the surface topography of carbon fibers. Specific area measurement, dynamic contact angle, and interfacial shear strength (IFSS) testing were performed to examine the effect of CNT on the interfacial properties of carbon fiber/PPEK composites. By the introduction of CNT to the interphase of carbon fiber‐reinforced PPEK composites, an enhancement of IFSS by 55.52% was achieved. Meanwhile, the interfacial fracture topography was also observed and the reinforcing mechanism was discussed. POLYM. COMPOS., 36:26–33, 2015. © 2014 Society of Plastics Engineers

Anion exchange membranes from brominated poly(aryl ether ketone) containing 3,5-dimethyl phthalazinone moieties for vanadium redox flow batteries

A series of heterocyclic poly(aryl ether ketone)s containing 3,5-dimethyl phthalazinone moieties were synthesized via the copolymerization of 4-(3,5-dimethyl-4-hydroxyphenyl)(2H)-phthalazin-1-one, 4-(4-hydroxyphenyl)(2H)-phthalazin-1-one and 4,4′-difluorobenzophenone. The resulting polymers were brominated with N-bromosuccinimide as the bromination reagent. Brominated poly(phthalazinone ether ketone) (BPPEK) with a degree of substitution in the range of 0.48–0.82 was obtained. Quaternized poly(phthalazinone ether ketone) anion exchange membranes (QBPPEK) were prepared from BPPEK membranes with trimethylamine as the amination reagent. Ion exchange capacity (IEC) values of the QBPPEK membranes were in the range of 0.82–1.53 mmol g−1. Compared with Nafion117 membrane, QBPPEK membranes showed much lower vanadium permeability. Coulombic efficiencies of the vanadium redox flow battery (VRB) with QBPPEK membranes were higher than that with the Nafion117 membrane. The energy efficiency of the VRB increased with an increase in the IEC of the QBPPEK membrane. The energy efficiency of the VRB cell with the QBPPEK membrane having an IEC of 1.53 mmol g−1 was 88%, which was higher than that of the cell with the Nafion117 membrane. During 100 charge–discharge cycles, the QBPPEK anion exchange membrane showed a stable performance.

Novel Crosslinked Alkaline Exchange Membranes Based on Poly(phthalazinone ether ketone) for Anion Exchange Membrane Fuel Cell Applications

ABSTRACTNovel crosslinked anion exchange membranes based on poly(phthalazinone ether ketone) (PPEK) were successfully prepared through chloromethylation, quaternization, membrane casting and OH‐ ionic exchange reaction from the quaternized PPEK (QPPEK) membrane. The quaternization was performed with N‐methylimidazolium (MIm) as ammonium agent and tetramethylethylenediamine (TMEDA) as crosslinking agent. The ion‐exchange capacity, swelling ratio (SR), water uptake (WU), and ionic conductivity of the QPPEK alkaline membranes have been systematically investigated. The results showed that QPPEK membranes have a high hydroxide conductivity and very low SR. For the QPPEK‐4 alkaline membrane with ion‐exchange capacity (IEC) 2.63 mmol/g, the WU was 35.8%, and the hydroxide conductivity was 0.028 S/cm at 30 °C and 0.032 S/cm at 70 °C, while its SR was only 7.6%. The thermal properties of the QPPEK alkaline membrane and CMPPEK were characterized using thermo‐gravimetric analysis measurements in a nitrogen atmosphere. The alkaline resistance of membrane QPPEK −4 was also briefly investigated in 6 M KOH at 60 °C. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1632–1638

Preparation and Properties of Poly (phthalazinone Ether Ketone) Based Anion Exchange Membranes for Vanadium Redox Flow Battery

Poly (phthalazinone ether ketone) anion exchange membranes with pyridinium groups (PyPPEK) for vanadium redox flow battery were prepared from chloromethylated poly (phthalazinone ether ketone) and pyridine. The chemical structure of PyPPEK was characterized by using FT-IR spectrum. Compared with quaternary ammonium group containing poly (phthalazinone ether ketone), PyPPEK membrane showed low ion exchange capacity, low swelling ratio and comparable tensile strength. Columbic efficiencies of VRB with anion exchange membranes were higher than that of VRB with Nafion117 membrane. When the ion exchange capacity of PyPPEK membrane was 1.40 mmol·g-1, energy efficiency of VRB with the membrane was higher than that of VRB with Nafion117 membrane at charge-discharge current densities ranging from 20 mA·cm-2 to 50 mA·cm-2.

Interfacial shear strength in carbon fiber‐reinforced poly(phthalazinone ether ketone) composites

We studied interfacial shear strength (IFSS) in carbon fiber (CF)‐reinforced poly (phthalazinone ether ketone) (PPEK) composites system, with emphasis on the influence of forming temperature of composite and sizing agent on CFs. To obtain apparent IFSS of CF‐reinforced PPEK composites shaped at various forming temperatures ranged from 20 up to 370°C, microbond test was carried out at single‐fiber composites. Results of microbond test showed that apparent IFSS was directly proportional to the difference between the matrix solidification temperature (forming temperature) and the test temperature and approximately 80% of the apparent IFSS in CF/PPEK composite system was attributed to residual radial compressive stress at the fiber/matrix interface. By sizing CF with sizing agent, the wettability of the fiber by the matrix was improved and the final apparent IFSS was also improved. POLYM. COMPOS., 34:1921–1926, 2013. © 2013 Society of Plastics Engineers

Fabrication and characterization of electrospun sulfonated poly(phthalazinone ether ketone) mats as potential matrix of reinforced proton exchange membranes

ABSTRACTIn this paper, the sulfonated poly(phthalazinone ether ketone) (SPPEK) nanofibers with low sulfonation degree are fabricated by electrospinning for the first time. The optimized concentration of SPPEK for electrospinning is 0.16 g ml−1 and the suitable solvent is the mixture of DMAc and NMP. The resulting SPPEK nanofibers show smooth surfaces and uniform diameters of about 50 nm. Proton conductivities of the SPPEK mat and membrane are tested and compared. The result indicates that the proton conductivity of the SPPEK mat is almost five times as high as that of the SPPEK membrane because of the formation of long‐range proton pathways on the surfaces of SPPEK nanofibers. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 4581–4586, 2013

Synthesis and Properties of Sulfonated Poly(phthalazinone ether ketone ketone)s Containing Pendant Phenyl Groups

Poly(phthalazinone ether ketone ketone)s with pendant phenyl groups(PPEKK-P) were synthesized via high temperature polycondensation from 4-(4-hydroxyphenyl)-2,3-phthalazin-1-ketone,4-(3-phenyl-4-hydroxyphenyl)-2,3-phthalazin-1-ketone and 1,4-bi(4-fluorobenzoyl)benzene(BFBB).A series of sulfonated poly(phthalazinone ether ketone ketone)s containing pendant phenyl groups(SPPEKK-P) was prepared from PPEKK-P with concentrated sulfuric acid as the sulfonating agent.The chemical structures of PPEKK-P and SPPEKK-P were characterized by FTIR and 1H NMR.SPPEKK-Ps proton exchange membranes were obtained by solution casting method.Water uptake,swelling ratio and proton conductivities of SPPEKK-Ps membranes increased with the increase of ion exchange capacity.The membranes exhibited good oxidative stability.The methanol permeability values of SPPEKK-Ps membranes were much lower than that of Nafion117 membrane.The proton conductivity of SPPEKK-P-100 membrane reached 7.44×10-2 S/cm at 95 ℃.

SPPEK/TPA composite membrane as a separator of vanadium redox flow battery

To improve the performance of a low cost sulfonated poly(phthalazinone ether ketone) (SPPEK) membrane in vanadium redox flow battery (VRFB), composite membranes composed of SPPEK and tungstophosphoric acid (TPA) with 8–25wt% concentration were prepared by solution casting. The results of scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD) of the SPPEK/TPA composite membrane revealed that TPA had excellent compatibility with SPPEK in the bulk of the membrane. The effect of the TPA concentration on the primary properties, permeability of vanadium ions and ionic selectivity, and chemical stability of the composite membrane was investigated. The single cell tests showed that the VRFB employing the SPPEK–TPA-17 membrane with 17wt% TPA exhibited a higher coulombic efficiency (98.75% vs. 92.81%) and energy efficiency (74.58% vs. 73.83%) than those of the Nafion system. Cycling and chemical stability tests indicated that the SPPEK/TPA composite membrane had high stability in the VRFB system.

Preparation and Physicochemical Property of Self-Crosslinked Poly(phthalazinone ether ketone) Anion-Exchange Membranes

Self-crosslinked poly(phthalazinone ether ketone) anion-exchange membranes(AEMs) were successfully fabricated from chloromethylated poly(phthalazinone ether ketone)(CMPPEK) by amination, membrane casting, and OH- exchange reaction steps. Triethylamine(TEA) was used as an ammonium agent, and diethylenetriamine(DETA) and diethylamine(DEA) were used as self-crosslinking agents in the quaternary reaction of CMPPEK, resulting in DETA-QPPEK-OH and DEA-QPPEK-OH AEMs, respectively. The chemical structures of DETA-QPPEK-OH and DEA-QPPEK-OH were characterized using Fourier transform infrared(FTIR) spectroscopy. The physicochemical properties of these AEMs were investigated including ion-exchange capacity(IEC), swelling ratios, water uptake, and ionic conductivities at 30 °C. The results showed that the swelling ratio of the DETA-crosslinked AEM was lower than that of the DEA- crosslinked AEM. This could be attributed to multi-crosslinking of multi-amino groups in the DETA structure. The temperature dependences of the ionic conductivities of the AEMs were measured from 30 to 80 °C. The ionic conductivities of the DEA-crosslinked and DETA-crosslinked AEMs were 0.060 and 0.028 S cm-1at 80 °C, respectively. The thermal stabilities of the resulting DETA-QPPEK-OH and DEA- QPPEK-OH membranes were investigated using thermogravimetric analysis(TGA), under a nitrogen atmosphere. The obtained membranes have high dimensional stabilities and are very promising for potential applications in anion-exchange membrane fuel cells(AEMFCs).

Poly(phthalazinone ether ketone ketone) anion exchange membranes with pyridinium as ion exchange groups for vanadium redox flow battery applications

Poly(phthalazinone ether ketone ketone) anion exchange membranes with pyridinium as anion exchange groups (PyPPEKK) were prepared by reacting chloromethylated poly(phthalazinone ether ketone ketone) membranes with pyridine in solution. The reaction conditions including diluent solvents, pyridine concentration, reaction time and temperature were investigated. Under the optimized reaction condition, PyPPEKK anion exchange membranes with IEC values in the range of 0.96–1.55 mmol g−1 and water uptake in the range of 10.2–16.5% were obtained. The swelling ratio of PyPPEKK membranes in deionized water and VOSO4 solution were in the range of 3.2–10.6% and 2.5–7.8%, respectively. PyPPEKK membranes showed good chemical stability in VO2+ solution. Notably, PyPPEKK membranes had higher coulombic efficiencies of VRB and much lower vanadium permeability compared with Nafion117 membrane. The energy efficiency of VRB with PyPPEKK membrane reached 83.6% at 80 mA cm−2 while the energy efficiency of VRB with Nafion117 membrane was 80.7% at the same charge–discharge current density. Furthermore, PyPPEKK membrane exhibited good performance in the 100-cycle charge–discharge VRB test.

Cell performance modeling of direct methanol fuel cells using proton-exchange solid electrolytes: Effective reactant diffusion coefficients in porous diffusion layers

The objective of this study is to develop a one-dimensional mathematical model for direct methanol fuel cell (DMFC) performance prediction. The modified model can be applied to DMFCs operated at wider ranges of methanol concentrations and temperatures with various solid electrolytes. Based on the model of Li et al. [J. Power Sources 154 (2006) 115–123], we propose a procedure to predict the effective diffusion coefficients of reactants (methanol and oxygen) in the diffusion layers to further estimate the limiting current densities. This approach does not use empirical fitting parameters and adopts the Darken equation and Boltzmann relationship to express the diffusivity dependency on the anode and cathode feed compositions. The diffusion layer porosity effect on the methanol and oxygen diffusion coefficients is accounted for using the Das equation. The proposed model is validated by experimental results obtained for 1–5 M of methanol feed at operating temperatures of 30–90 °C using Nafion, sulfonated poly(phthalazinone ether ketone), and sulfonated poly(ether ether ketone) electrolytes. The predictions are in good agreement with the experimental data. This model is helpful for researchers in estimating cell performance by eliminating the costs involved with preparing single cells during new material development.

Properties of carbon fiber sized with poly(phthalazinone ether ketone) resin

AbstractWe studied thermoplastic poly(phthalazinone ether ketone) (PPEK) resin as a sizing agent on carbon fiber, with emphasis on its thermal stability, surface energy, wetting performance, and interfacial shear strength (IFSS). X‐ray photoelectron spectroscopy characterization was carried out to study the chemical structure of sized/unsized carbon fibers. Scanning electron microscopy and atomic force microscopy were used to characterize surface topography. TGA was used to analyze the thermal stability. Meanwhile, contact angle measurement was applied to analyze the compatibility between the carbon fibers and PPEK and the surface energy of carbon fibers. IFSS of carbon fiber/PPEK composite was examined by microbond testing. It is found that carbon fibers uniformly coated with PPEK resin had better thermal stability and compatibility with PPEK resin than the uncoated fiber. The contact angle is 57.01° for sized fibers, corresponding to a surface energy of 49.96 mJ m−2, much smaller than that for unsized ones with contact angle value of 97.05°. The value of IFSS for sized fibers is 51.49 MPa, which is higher than the unsized fibers. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

Quaternized poly(phthalazinone ether ketone ketone) anion exchange membrane with low permeability of vanadium ions for vanadium redox flow battery application

To develop cost-effective membranes with low permeability of vanadium ions for vanadium redox flow battery (VRB) application, an inexpensive precursor membrane material, chloromethylated poly(phthalazinone ether ketone ketone), is first prepared from poly(phthalazinone ether ketone ketone) with nitrobenzene as the solvent, and then reacted with trimethylamine to form quaternized poly(phthalazinone ether ketone ketone) (QAPPEKK) anion exchange membranes. At an ion exchange capacity of 1.56 mmol g−1, the QAPPEKK membrane shows much lower permeability of vanadium ions (0.17 × 10−4 cm min−1 for V3+ and 0.21 × 10−4 cm min−1 for VO2+) than that of Nafion117 membrane (1.34 × 10−4 cm min−1 for V3+ and 1.19 × 10−4 cm min−1 for VO2+), resulting in higher coulombic efficiency (99.4% at 80 mA cm−2). In addition, the energy efficiency of the VRB with QAPPEKK membrane is comparable to that of VRB with Nafion117 membrane. Moreover, the QAPPEKK membrane is stable in VO2+ electrolyte, and exhibits good performance in the 100-cycle charge-discharge test of VRB.

Morphology and Proton Conductivity of Composite Membranes Based on PWA and PPEK

A series of HPA-containing Poly(phthalazinone ether ketone) (PPEK) membranes was prepared and their microstructure and conductivities were studied in this work. The results showed the composite membrane had no proton conducting ability with PWA content less than 75%, while the conductivity for the PWA/(PEEK-PVP) membranes with 35% of PWA was higher than 4×10-4 S/cm. Proton conductivities up to 4.86×10-3 S/cm have been measured at temperatures up to at 140°Cand 100% RH for PWA/(PEEK-PVP) membranes with 35% of PWA and 70% PVP. The relationship of conductivity and the morphology of the PPEK/PWA membranes showed that the PWA particle dispersion is the key parameters.

Curing Kinetics of DGEBA Epoxy Resin Modified by Poly (phthalazinone ether ketone) (PPEK)

The cure kinetics of diaminodiphenylsulfone-cured diglycidyl ether of bisphenol A epoxy resin (DGEBA) and its blends with poly (phthalazinone ether ketone) (PPEK) were investigated by isothermal differential scanning calorimetry (DSC). The results were applied to the Arrhenius equation and the phenomenological model of Kamal. The Arrhenius activation energy increased with increasing PPEK content. The experimental reactions rates agreed well with that of the theoretical in the initial stages of the reaction, but diffusion control was incorporated to describe the cure in the latter stages. The cure mechanism remained broadly autocatalytic in nature regardless of PPEK concentration and the cure temperature.

Synthesis and characterization of phthalazinone‐based poly(aryl ether ketone) derived from 4,4′‐dichlorobenzophenone

AbstractAs distinguished from the conventional preparation of poly(aryl ether ketone)s utilizing 4,4′‐difluorobenzophenone, a novel synthetic method of high molecular weight poly(phthalazinone ether ketone) derived from 4,4′‐dichlorobenzophenone was studied. Reaction conditions to get high molecular weight polymer were investigated in details. Experimentally, sulfolane was chosen as the reaction media and high molecular weight polymer could be obtained in 7–8 hr at 210°C. The cyclic oligomers in the polymer product reduced to below 3.0% when the concentration of the reactant is 1.6–1.7 g/ml. Fourier transform infrared (FT‐IR), 1H NMR, and elemental analysis were used to confirm the structure of the obtained polymer. The amorphous polymer showed reasonable solubility in selective solvent, such as chloroform and N‐methyl‐2‐pyrrolidone, and tough, flexible, and transparent thin film can be readily prepared from their N‐methyl‐2‐pyrrolidone solution. The obtained polymer showed high glass transition temperature (Tg) up to 261°C detected by differential scanning calorimetry (DSC), and the temperature of 5% weight loss under nitrogen higher than 500°C detected by thermal gravimetric analysis (TGA), indicating its excellent thermal stability. Copyright © 2011 John Wiley & Sons, Ltd.

Preparation of chloromethylated/quaternized poly(phthalazinone ether ketone) anion exchange membrane materials for vanadium redox flow battery applications

Chloromethylated poly(phthalazinone ether ketone) (CMPPEK) was prepared from poly(phthalazinone ether ketone), with chloromethyl methyl ether (CME) as the chlromethylating reagent and concentrated sulfuric acid as the solvent. The effects of CME quantity, reaction temperature, and reaction time on degree of chloromethylation (DCM) were investigated. CMPPEK with DCM ranging from 0.73 to 2.32 mmol g −1 were obtained. CMPPEK were characterized with 1H NMR and TGA. CMPPEK membranes were prepared from CMPPEK/ N-methyl-2-pyrrolidinone casting solutions. Quaternized poly(phthalazinone ether ketone) (QAPPEK) anion exchange membranes were prepared from CMPPEK membranes with different DCM. The ion exchange capacity (IEC) and water content (Wc) of QAPPEK membranes were studied. QAPPEK membranes exhibited IEC ranging from 0.70 to 2.04 mmol g −1 and Wc ranging from 12.9 to 52.3%. IEC and Wc of QAPPEK increased with an increase in DCM of CMPPEK. The vanadium ion permeability of QAPPEK membranes was much lower than that of Nafion117 membrane. The performance of vanadium redox flow battery (VRB) single cell with QAPPEK membranes was investigated. Compare to VRB cell with Nafion117 membrane, the VRB single cell with QAPPEK membranes exhibited higher columbic efficiency. The results show that QAPPEK membranes could be promising anion exchange membranes for VRB applications.

Characterization and tribological investigation of self-assembled trimethoxysilyl-functionalized poly (phthalazinone ether ketone) thin films on glass substrates

Trimethoxysilyl-functionalized PPEK (PKGS) films had been designed to serve as wear resistant coatings for silicon surfaces. These surface films were formed by a dip-coating technique applied to self-assembled monolayers (SAMs). The formation and wetting behavior of PKGS films were characterized by means of contact angle measurement. The friction coefficient of the film prepared is very low (about 0.1), and the anti-wear behavior is good, with a lack of failure after sliding over 1800 s.

Synthesis and characterization of multiblock copolymer ionomers containing phthalazinone ether ketone and fluorene ether ketone moieties

AbstractTwo series of sulfonated multiblock copoly(ether‐ketone)s containing phthalazinone ether ketone and fluorene ether ketone moieties have been synthesized successfully by two‐step polycondensation. The water uptakes of the copolymers with varying sized sulfonated poly(phthalazinone ether ketone) block as hydrophilic blocks are moderate. In this series, polymer 10a gave the proton conductivity of 1.20 × 10−3 S/cm with IEC of 1.03. The water uptakes of the copolymers with varying sized sulfonated poly(fluorene ether ketone) blocks as hydrophilic blocks are high than 300%. These copolymers showed better proton conductivity. The copolymers with sulfonated poly(phthalazinone ether ketone) blocks had strong alcohol resistance at refluxing temperature. Whereas the copolymers containing sulfonated poly(fluorene ether ketone) hydrophilic blocks were dissolved in methanol and ethanol. The cast films of the title ionomers were transparent, ductile, and flexible. Moreover, these copolymers demonstrated greatly improved oxidative and thermal stabilities. Especially, the copolymers comprising sulfonated poly(phthalazinone ether ketone) hydrophilic blocks and poly(fluorene ether ketone) hydrophobic blocks is a promising proton exchange membrane material for proton exchange membrane fuel cell used methanol or ethanol as fuel. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010