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The poly(aryl ether ketone) with spatial cardo structure is prepared from 4,4′-bis(phenoxy)benzophenone and 1-(4-bromobutyl)indoline-2,3-dione through a facile polyhydroxyalkylation reaction catalyzed by superacid. The number average molecular weight of the resultant polymer is achieved as high as 105.6 kg mmol−1. Three anion exchange membranes were prepared by reacting the polymer with trimethylamine, N-methyl-piperidine, and N,N,N′,N′,N″-pentaethylguanidine, respectively. Among the prepared membranes, N-methyl-piperidine based anion exchange membrane exhibited the highest OH− conductivity of 99.8 mS cm−1 at corresponding IEC of 1.54 meq g−1. In addition, the prepared membranes also exhibit excellent mechanical properties, in which the tensile strength and elongation at break can reach up to 50 MPa and 35%, respectively. Moreover, the anion exchange membranes exhibited good alkaline stability. When they were treated with 1 M KOH at 60 °C for 600 h, their conductivity decreased by less than 5%.

A series of comb-like amphiphilic copolymers (PES-g-PEO) were synthesized through grafting poly(ethylene oxide) (PEO) to cardo poly(aryl ether sulfone) (PES-NH) backbone. By controlling the ratios of PEO and cardo poly(aryl ether sulfone), amphiphilic copolymers with a range of PEO side chain were obtained and were employed to ultrafiltration (UF) membranes. The PES-g-PEO-XX materials showed high thermal stability (Td > 238 °C) and good mechanical properties especially elongation at break reached to 150% compared to 23% of PES-NH. The contact angle of PES-g-PEO-80 asymmetric membrane was decreased to a slow as 59° which was 30° lower than the value of PES-NH membrane (90°), indicating that PES-g-PEO-80 membrane exhibited remarkable hydrophilic property. No protein adsorption was found on the surface of PES-g-PEO-60 and PES-g-PEO-80 membranes, showing excellent antifouling properties compared to PES-NH. The results of this work suggest that PES-g-PEO copolymers are promising materials for the fabrication of fouling resistant membranes.

We report a new hydroxyl functionalized microporous organic polymer (MOPOH) based on the polymerization of catechol with terephthalaldehyde using phenolic resin-inspired chemistry. This catechol-decorated material, with surface area of 874 m2 g−1 and micro, mesopores, facilitates the immobilization and dispersion of Pd nanoparticles (NPs) on the polymer matrix. The surface area of the created composite (Pd@MOPOH) decreases to 419 m2 g−1 and the pore size distribution is narrowly distributed at 1.54 nm due to the filling of mesopores. The CO2 capture capacities for MOPOH and Pd@MOPOH at 273 K and 1 bar are 13.4 and 9.2 wt%, respectively. The resultant Pd NPs are crystalline and uniform with a mean diameter of 4.8 nm. The well-dispersed Pd@MOPOH exhibits excellent catalytic activity toward the model reduction of 4-nitrophenol into 4-aminophenol. Significantly, nearly no Pd leaching is detected during the catalytic cycles, showing active and durable nature of the heterogeneous nanocatalyst.

This article describes the synthesis and characterization of microporous organic copolymers (PP-N-x, where "x" is the molar percent of triphenylamine) prepared from triphenylamine and dichloro-p-xylene using a combination of oxidative polymerization and Friedel Crafts alkylation process promoted by anhydrous FeCl3. The samples possessed BET specific surface areas from 318 to 1530 m(2) g(-1) with the increasing content of dichloro-p-xylene. The highest CO2 uptake of 4.60 mmol g(-1) was observed for PP-N-25, which was one of the highest values among MOPs reported to date under these conditions. The polymers possessed stable and reversible CO2 adsorption-desorption performance in at least 5 consecutive runs without noticeable deterioration of CO2 uptake capacities. (C) 2013 Elsevier Ltd. All rights reserved.

Novel cardo poly(aryl ether sulfone)s containing pendent -[CH2CH2NMe3]+OH-, or -[CH2CH2CH2NMe3]+OH- groups, and partially fluorinated cardo poly(aryl ether sulfone) containing pendent -[CH2CH2CH2NMe3]+OH- groups were synthesized and examined with the focus of understanding how the polymer chemical structure affects their morphology, ion conductivity and alkaline stability. The resulting quaternized polymers exhibited outstanding solubility in polar aprotic solvents. The partially fluorinated cardo poly(aryl ether sulfone)s (PES-PF-OH) with ion-exchange capacity of 1.44 meg g(-1) displayed the highest ion conductivities, varied from 3.0 x 10(-2) to 4.1 x 10(-2) S cm(-1) over the range 20-60 degrees C. TEM revealed that PES-PF-OH membrane exhibited a distinct phase-separated morphology comprised of interconnected ionic clusters in size of 1-2 nm. The studies on alkaline stability of the membranes revealed that the PES-PF-OH polymer was not stable under strong basic conditions. The quarternized polymers containing pendent -[CH2CH2NMe3]+OH-, or -[CH2CH2CH2NMe3]+OH- groups mainly underwent Hofmann elimination and S(N)2 substitution reaction. (C) 2010 Elsevier Ltd. All rights reserved.

A sulfonated poly[bis(benzimidazobenzisoquinolinones)] (SPBIBI) possessing a conjugated pyridinone ring was shown to be effective for dispersing multiwalled carbon nanotubes (MWCNTs) in DMSO. The dispersions in which the SPBIBI to MWCNTs mass ratio was 4:1 demonstrated the highest MWCNTs concentrations, i.e., 1.5-2.0 mg mL(-1), and were found to be stable for more than six months at room temperature. Through casting of these dispersions, MWCNTs/SPBIBI composite membranes were successfully fabricated on substrates as proton exchange membranes for fuel cell applications and showed no signs of macroscopic aggregation. The properties of composite membranes were investigated, and it was found that the homogeneous dispersion of the MWCNTs in the SPBIBI matrix altered the morphology structures of the composite membranes, which lead to the formation of more regular and smaller cluster-like ion domains.

A novel triptycene-based dianhydride, 1,4-bis[4-(3,4-dicarboxylphenoxy)]triptycene dianhydride, was prepared from 4-nitro-N-methylphthalimide and potassium phenolate of 1,4-dihydroxytriptycene (1). The aromatic nucleophilic substitution reaction between 4-nitro-N-methylphthalimide and I afforded triptycene-based bis(N-methylphthalimide) (2), which hydrolyzed and subsequently dehydrated to give the corresponding dianhydride (3). A series of new polyimides containing triptycene moieties were prepared from the dianhydride monomer (3) and various diamines in in-cresol via conventional one-step polycondensation method. Most of the resulting polyimides were soluble in common organic solvents, such as chloroform, THF, DMAc and DMSO. The polyimides exhibited excellent thermal and thermo-oxidative stabilities with the onset decomposition temperature and 10% weight loss temperature ranging from 448 to 486 degrees C and 526 to 565 degrees C in nitrogen atmosphere, respectively. The glass transition temperatures of the polyimides were in the range of 221-296 degrees C. The polyimide films were found to be transparent, flexible, and tough. The films had tensile strengths, elongations at break, and tensile moduli in the ranges 95-118 MPa, 5.3-16.2%, and 1.03-1.38 GPa, respectively. Wide-angle X-ray diffraction measurements revealed that these polyimides were amorphous.