Proton-Exchange Sulfonated Poly （ether ether ketone） （SPEEK）/SiOx-S Composite Membranes in Direct Methanol Fuel Cells

A sulfonated poly（ether ether ketone） （SPEEK） membrane with a fairly high degree of sulfonation （DS） can swell excessively and even dissolve at high temperature. To solve these problems, insolvable functionalized silica powder with sulfonic acid groups （SiOx-S） was added into the SPEEK matrix （DS = 55.1%） to prepare SPEEK/ SiOx-S composite membranes. The decrease in both the swelling degree and the methanol permeability of the membranes was a dose-dependent result of addition of the SiOx-S powder. Pure SPEEK membrane swelled 52.6% at 80℃, whereas the SPEEK/SiOx-S （15%, by mass） membrane swelled only 27.3% at the same temperature. From room temperature to 80℃, all SPEEK/SPEEK/SiOx-S composite membranes had methanol permeability of about one order of magnitude lower than that ofNafion115. Compared with pure SPEEK membranes, the addition of the SiOx-S powder not only leads to higher proton conductivity, but also increases the dimensional stability at higher temperatures, and greater proton conductivity can be achieved at higher temperature. The SPEEK/SiO4-S （20%, by mass） membrane could withstand temperature up to 145℃, at which in 100% relative humidity （RH） its proton conductivity exceeded slightly that of Nafion 1 15 membrane and reached 0.17 S·cm^-1, while pure SPEEK membrane dissolved at 90℃. The SPEEK/SiOx-S composite membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.

Proton-exchange Sulfonated Poly（ether ether ketone）/Sulfonated Phenolphthalein Poly（ether sulfone） Blend Membranes in DMFCs

A sulfonated poly（ether ether ketone） （SPEEK） membrane with fairly high degree of sulfonation （DS） swells excessively and even dissolves at high temperature. To solve these problems, sulfonated phenolphthalein poly（ether sulfone） （SPES-C, DS= 53.7%） is blended with the SPEEK matrix （DS= 55.1%, 61.7%） to prepare SPEEKJSPES-C blend membrane. The decrease in swelling degree and methanol permeability of the membrane is dose-dependent. Pure SPEEK （DS = 61.7%） membrane dissolves completely in water at 70℃, whereas the swelling degree of the SPEEK （DS = 61.7%）/SPES-C （40%, by mass） membrane is 29.7% at 80℃. From room temperature to 80℃, the methanol permeability of all SPEEK （DS = 55.1%）/SPES-C blend membranes is about one order of magnitude lower than that of Nafion 115. At higher temperature, the addition of SPES-C polymer increases the dimensional stability and greater proton conductivity can be achieved. The SPEEK （DS = 55.1%）/SPES-C （40%, by mass） membrane can withstand temperatures up to 150℃. The proton conductivity of SPEEK （DS = 55.1%）/SPES-C （30%, by mass） membrane approaches 0.16 S·cm^-1, matching that of Nafion 115 at 140℃ and 100% RH, while pure SPEEK （DS = 55.1%） membrane dissolves at 90℃. The SPEEK/SPES-C blend membranes are promising for use in direct methanol fuel cells because of their good dimensional stability, high proton conductivity, and low methanol permeability.

Synthesis and properties of soluble poly（aryl ether sulfone ether ketone）s copolymers containing pendant methyl groups

A series of Poly（arly ether sulfone ether ketone）s containing pendant methyl groups were synthesized by the reaction of 4,4＇-[sulfonylbis （1,4-phenylene）dioxy] dibenzoyl chloride （SODBC） with 4,4＇- diphenoxy diphenylsulfone （DPODPS）, 4,4＇- di（2-methylphenoxy） diphenylsulfone （o-Me-DPODPS）, 4,4＇- di（3-methylphenoxy） diphenylsulfone （m-Me-DPODPS）, 4,4＇- di （2,6-bimethylphenoxy） biphenylsulfone（o-Me2-DPODPS） respectively, in a mixture of 1,2-dichloroethane （DCE） and N-methylpyrrolidone （NMP）. These reactions were catalyzed by anhydrous aluminum chloride （AlCl）. The characteristic of copolymers were studied by means of advanced analytical techniques such as FT-IR,1H-NMR, DSC, TGA and WAXD. The results show glass transition temperature （Tg） in the range of 193-206℃, thermally stable in excess of 434℃ and excellent solubility in polar solvents. Methyl-substituted Poly（aryl ether sulfone ketone）s had higher glass transition temperatures, lower initial decomposition temperatures than the unsubstituted ones.

Ketone bodies and inflammation modulation:A mini-review on ketogenic diet’s potential mechanisms in mood disorders

Mental disorders such as depression and anxiety inflict significant burdens on individuals and society.Commonly prescribed treatments often involve cognitive therapy and medications.However,for patients resistant to these conventional methods,alternative therapies like the Ketogenic Diet(KD)offer a promising avenue.KD and its key metabolite,β-hydroxybutyrate(BHB),have been hypothesized to alleviate mental disorders through antiinflammatory actions,a crucial pathway in the pathophysiology of depression.This mini-review examines 15 clinical trials exploring the influence of KD and BHB on inflammation and their potential roles in managing mental disorders.Both human and animal studies were scrutinized to elucidate possible cellular and molecular mechanisms.Out of the 15 trials,10 reported reduced levels of at least one inflammatory mediator or mRNA post KD or BHB treatment,while two observed an elevation in anti-inflammatory agents.These findings suggest that KD and BHB could modulate cellular inflammatory pathways,highlighting their potential for therapeutic application in mental disorders.

Copper-Catalyzed C-C(O)C Bond Cleavage of Monoalkylated β-Diketone: Synthesis of α,β-Unsaturated Ketones

A new and simple route for the synthesis of α,β-unsaturated ketones via cleavage of the C-C(O)C single bond of monoalkylated β-diketone has been described. The reaction was catalyzed by copper, a cheap transition metal in a weakly basic medium (K3PO4) at room temperature. To carry out this study, we first had to synthesize the monoalkylated β-diketones 1. Afterwards, α,β-unsaturated ketones 2 were obtained with high yields around 80%. Finally, all the products were characterized by 1H NMR, 13C NMR, and HRMS spectra. .

SYNTHESIS AND PROPERTIES OF NOVEL POLY(IMINO KETONE)S AS HIGH-PERFORMANCE POLYMERS

Di(4-bromophenyl)ketone and various aromatic diamines as the monomers,a series of novel poly(imino ketone)s (PIKs)have been synthesized via palladium-catalyzed aryl amination,which is Hartwig-Buchwald polycondensation reaction.The structures of PIKs are characterized by means of elemental analysis,FT-IR,~1H-NMR and UV-Vis spectroscopy. The results show a good agreement with the proposed structure.The general properties of PIKs are studied by DSC,TG and wide-angle X-ray diffraction,the solubility behavior is...

Synthesis and characterization of quaternized poly(phthalazinone ether sulfone ketone)for anion-exchange membrane

Chloromethylated poly（phthalazinone ether sulfone ketone） （CMPPESK） was prepared from poly（phthalazinone ether sulfone ketone） （PPESK） using chloromethyl octyl ethers （CMOE） with lower toxicity as chloromethylated regent. CMPPESK was soluble in N-methyl-2-pyrrolidone （NMP）, N,N-dimethylacetamide （DMAc） and chloroform. Quaternized poly（phthalazinone ether sulfone ketone） （QAPPESK） was prepared from CMPPESK by quaternization. QAPPESK had excellent solvent resistance, which was only partly soluble in sulfuric acid （98%） and swollen in N,N-dimethylformamide （DMF）. The vanadium redox flow battery （V-RFB） using QAPPESK anion-exchange membrane had better performance with 88.3% of overall energy efficiency.

UV-induced Self-initiated Graft Polymerization of Acrylamide onto Poly(ether ether ketone)

Photo-grafting of hydrophilic monomer was used to enhance the hydrophilicity of poly（ether ether ketone） （PEEK） with the aim of extending its applications to biological fields. PEEK sheets were surface modified by grafting of acrylamide（AAm） with ultraviolet（UV） irradiation in the presence or absence of benzophenone（BP）. The effects of BP, irradiation time and monomer concentration on the surface wettability of PEEK were investigated. Characteriza tion of modified PEEK using scanning electron microscopy（SEM）, energy-disperse spectrometer（EDS） and water contact angle measurements shows that AAm was successfully grafted on PEEK surface both in presence and absence of BP. With the increase in irradiation time and monomer concentration, contact angles decrease to as low as 30°, demonstrating a significant improvement of surface hydrophilicity. In agreement with the decrease in contact angle, under identical conditions, the nitrogen concentration increases, suggesting the increase in grafting degree of the grafting polymerization. This investigation demonstrates a self-initiation of PEEK due to its BP-like structure in the backbone of the polymer. Though the graft polymerization proceeds more readily in the presence of BP, the self-initiated graft polymerization is clearly observed.

Synthesis and characterization of novel poly(aryl ether sulfone ketone)s containing phthalazinone and biphenyl moieties

A novel series of poly（aryl ether sulfone ketone）s （PPESKs） containing phthalazinone and biphenyl moieties were prepared by two-step nucleophilic polycondensation reaction. The ^-Mw values of these copolymers were between 38,330 and 67,900. The glass transition temperatures （Tg） and 5% decomposition temperatures were ranged in 253-269 ℃ and 488-500 ℃, respectively, The structures of these copolymers were confirmed by FT-IR and ^1H NMR. Moreover, all the resultant copolymers were amorphous determined by wide angle X-ray diffraction （WAXD）.

Immobilization of Bovine Serum Albumin on Poly(ether ether ketone) for Surface Biocompatibility Improvement

UV-induced graft polymerization of acrylic acid（AA） on poly（ether ether ketone）（PEEK） films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin（BSA）.BSA was introduced on PEEK surface based on the condensation reaction between ―NH 2 and ―COOH.The modified surface（PEEK-BSA） was characterized by energy-disperse spectrometry（EDS）,X-ray photoelectron spectroscopy（XPS）,water contact angle measurement and UV spectrum analysis.The contact angle was found to decrease from 104° for the virgin PEEK films to 63° for the BSA-immobilized PEEK films,demonstrating a significant improvement of surface hydrophilicity.Moreover,the appearance of nitrogen on PEEK film confirmed by XPS and EDS indicates the immobilization of BSA on PEEK surface.

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.

Poly(ether ether ketone ketone) based imidazolium as anion exchange membranes for alkaline fuel cells

An imidazolium functionalized poly(ether ether ketone ketone)(PEEKK-DIm OH)anion exchange membrane(AEM)readily soluble in certain low-boiling-point solvents(isopropanol)is prepared.The solubility results are consistent with the results of molecular dynamics simulations.By varying the chloromethylation reaction temperature or concentrated sulfuric acid concentration of PEEKK,the degrees of chloromethylation of PEEKK are changed from 54% to 92%,the corresponding PEEKK-DIm OH AEMs with the ion exchange capacities(IECs)of 1.14–1.65 mmol·g^(-1).The PEEKK-DIm OH 92% AEM shows high hydroxide conductivity(31 m S·cm^(-1)),suitable water uptake(94%)and acceptable swelling ratio(39%)at 60°C.In addition,the PEEKK-DIm OH AEMs possess good thermal and alkaline stability.The maximum power density(46.16 mW·cm^(-2))of fuel cell prepared with PEEKK-DIm OH 92%AEM as exchange membrane and ionomer is much higher than that with commercial AHA membranes.All the above results indicate that the PEEKK used in this study is a promising AEM matrix material for alkaline fuel cells.

STRUCTURE AND PROPERTIES OF PHOSPHROUS-CONTAINING POLY(ARYLETHER KETONE)WITH BISPHENOL-A MOIETY

A phosphrous-containing poly（aryl ether ketone） was synthesized derived from bisphenol-A and bis[4-（4- fluorobenzoyl）phenyl] phenyl phosphine oxide （FPPPO） by nucleophilic substitution reaction. The structure of the polymer was characterized by FT-IR, ^1H-NMR and ^31p-NMR. The thermal property of the PAEK was measured by DSC and TGA. The glass transition temperature （Tg） of the polymer was 205℃, and the 5% weight loss temperature under nitrogen was 475℃. Good solubility of the polymer in organic solvents, such as N-methylpyrrolidone, dimethylformamide, dimethylacetamide, dimethylsulfoxide and chloroalkanes was observed, flexible film was obtained from the polymer＇s CH2Cl2 solution. The limiting oxygen index （LOI） of the PAEK was 40, which indicated that organic phosphorus moiety can offer good flame retardant property to the polymer.

Synthesis and Properties of Poly(aryl ether ketone) Copolymers Containing 2,7-Naphthalene Moieties

Poly（ aryl ether ketone） copolymers containing 2,7-naphthylene and hydroquinone（HQ） moieties with various compositions were prepared by the reaction of 4,4＇-difluorobenzophenone（DFB） 2,7-naphthylene and hydroquinone in the presence of sodium carbonate and potassium carbonate （ 19： 1, mass ratio） in diphenyl sulfone （DPS）. The thermal analysis results of the copolymers show that the glass transition temperatures（Tgs） increase, while the melting temperatures（Tra） and tile 5.0% weight loss temperatures （ Td ） decrease with the increase of the 2,7-naphthalene moieties. For the copolymers synthesized at a molar fraction of 2,7-naphthalene in the difluoro monomers being over 0.30, no peaks corresponding to the cold crystallization temperature and the melting temperature could be detected, indicating that these copolymers are almost amorphous. The crystal structures of the copolymers with a molar fraction of 2,7-naphthalene being less than 0. 30 are rhombic.

Evaluation of Stabilization Performances of Antioxidants in Poly(ether ether ketone)

Two types of antioxidants（a primary antioxidant and a secondary antioxidant） were used to improve the stability of poly（ether ether ketone）（PEEK）. The effects of the antioxidants on the properties of PEEK and the stabilization mechanism were investigated by some characterization methods, such as rheometer, thermogravimetric ana- lysis（TGA）, universal tester and electron spin resonance（ESR）. The results indicate that the efficiency of the phosphorous antioxidant（DS） in improving the stability of PEEK was better than that of the phenolic antioxidant（DN） in both melting stability and thermal stability, and the thermal stability of PEEK sample containing 0.07%（mass fraction） DS was the best among all the samples due to the decrease of the free radicals density, as proven by ESR measurement. Additionally, no obvious changes could be observed in mechanical properties of PEEK containing antioxidants compared to those of virgin PEEK.

Sulfonated fluorinated multi-block copolymer hybrid containing sulfonated(poly ether ether ketone) and graphene oxide: A ternary hybrid membrane architecture for electrolyte applications in proton exchange membrane fuel cells

A ternary hybrid membrane architecture consisting of sulfonated fluorinated multi-block copolymer （SFMC）, sulfonated （poly ether ether ketone） （SPEEK） and I or 5 wt% graphene oxide （GO） was fabricated through a facile solution casting approach. The simple, but effective monomer sulfonation was performed for SFMC to create compact and rigid hydrophobic backbone structures, while conventional random sulfonation was carried-out for SPEEK. Hydrophilic-hydrophobic-hydrophilic structure of SFMC enhances the compatibility with SPEEK and GO and allows for an unprecedented approach to alter me- chanical strength and proton conductivity of ternary hybrid membrane, as verified from universal test machine （UTM） curves and alternating current （AC） impedance plots. The impact of GO integration on the morphology and roughness of hybrid membrane was scrutinized using field emission scanning electron microscope （FE-SEM） and atomic force microscope （AFM）. Ternary hybrid showed uniform intercalation of GO nanosheets throughout the entire surface of membrane with an increased surface roughness of 8.91 nm. The constructed ternary hybrid membrane revealed excellent water absorption, ion exchange capacity and gas barrier properties, while retaining reasonable dimensional stability. The well-optimized ternary hybrid membrane containing 5 wt% GO revealed a maximum proton conductivity of 111.9 mS/cm, which is higher by a factor of two-fold with respect to that of bare SFMC membrane. The maximum PEMFC power density of 528.07mW/cm2 was yielded by ternary hybrid membrane at a load current density of 1321.1 mA/cm2 when operating the cell at 70 ℃ under 100% relative humidity （RH）. In comparison, a maximum power density of only 182.06 mW/cm2 was exhibited by the bare SFMC membrane at a load current density of 455.56 mA/cm2 under same operating conditions.

Analysis of Solvent Effect on Mechanical Properties of Poly(ether ether ketone) Using Nano-indentation

Poly（ether ether ketone） （PEEK） is a high-performance semi-crystalline thermoplastic polymer. Exposure of the polymeric surface to solvents can have a strong effect like softening/swelling of polymeric network or dissolution. In this study, nano-indentation analysis was performed to study the effect of acetone on the surface mechanical properties of PEEK using different exposure time. The experiments were performed with a constant loading rate （10 nrn/s） to a maximum indentation displacernent （1000 nrn）. A 30-second hold segrnent was included at the maximum load to account for any creep eft）ors followed by an unloading segrnent to 80% unloading. The indentation hardness and the elastic modulus were corn- puted as a continuous function of the penetration displacernent in the continuous stiffness mode （CSM） indentation. The experirnental data showed that the peak load decreased from -5.2 mN to -1.7 mN as exposure tirne in solvent environrnent increased from 0 to 18 days. The elastic modulus and the hardness of PEEK samples also displayed a decreasing trend as a function of exposure tirne in the solvent environrnent. Two empirical models were used to fit the experirnental data of hardness as a function of exposure tirne which showed a good agreernent with the experirnental values.

Preparation and Characterization of Low Density Poly(Imino Imino Ketone)Foam

Poly（Imino Ketone） （PIK） is a group of novel high performance polymer material with excellent thermal properties and dissolubility. Aiming at the requirements of inertial confined fusion （ICF） studies on low density polymer foams, we firstly synthesized poly（imino imino ketone） （PIIK） by palladium catalyzed C-N cross-coupling reaction, and successfully prepared the PIIK foam material with a density of 80-300 mg/cm3 by using PIIK as the raw material with thermal-induced phase separation and lyophilization technique. Mercury injection method was used to determine the structure of PIIK foams, and the results indicated that the mean pore diameter was lower than 5 ~tm and it had relatively high voidage and specific surface area.

Preparation of Anion Exchange Membrane Based on Imidazolium Functionalized Poly（arylene ether ketone）

The authors presented a novel synthetic route for the imidazolium functionalized poly（arylene ether ke- tone）s, derived from an engineering plastics polymer, a poly（arylene ether ketone） with 3,3＇,5,5＇- tetramethyl-4,4＇-dihydroxybiphenyl moiety（PAEK-TM）. The preparation of anion exchange membranes comprised converting benzylic methyl groups to bromomethyl groups by a radical reaction, followed by the functionalization of bromomethylated PAEK with alkyl imidazoles, i.e., methyl, butyl or vinyl imidazole. The structure of imidazolium functionalized PAEK was proved by 1H NMR spectra. A class of flexible and tough membranes was then achieved by subsequent film-forming and anion exchange processes. The water uptake and hydroxide conductivities of mem- branes are comparable or superior to those of quaternary ammonium（QA） anion exchange membranes. This work demonstrated a new route for non-QA anion exchange membrane design, avoiding the chloromethylation reagent and oreciselv controlling the degree and location of imidazolium grouos.

Synthesis of Poly(aryl ether ketone) Copolymers Containing Adamantyl-substituted Naphthalene Rings

High performance polymers have received considerable attention over the past decade owing to their increased demands as replacements for metals or ceramics in automotive, aerospace, and microelectronic industries. Poly（aryl ether ketone）s（PAEKs） are a class of important high-performance aromatic polymers with excellent mechanical properties, good solvent resistance, size-accuracy, electrical characteristics, and superior thermal stability. However,