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Water soluble bis(acetonitrile) diphospalladium (II) complexes cis‐[Pd(L1–L5)(NCCH3)2][BF4]2 (C1–C5) were obtained by the reaction [Pd(NCCH3)4][BF4]2 with diphosphines ligands L1–L5 (CH2(CH2PR2)2: where R=(CH2)nP(O)(OEt)2, n=2–4, n=6 and n=8)) in dichloromethane–acetonitrile. The isolated complexes were characterized by elemental analysis, FTIR, 1H‐ and 31P‐NMR spectroscopy. The complexes were applied as catalysts for the copolymerization of 1‐butene with carbon monoxide in aqueous media. The present work emphasized on the effect of weakly coordinated solvent and counterion on the catalytic behavior of cis‐[Pd(L1–L5)(NCCH3)2][BF4]2 complexes compared to previously prepared cis‐[ Pd(L1–L5)(OAc)2] (A1–A5). The exchange of π‐bonding NCCH3 ligand with π‐bonding CO and alkene was more favored than the exchange of σ‐bonding OAc− as reflected by the much higher catalytic activity (TON) of the former compared to the latter. In order to compare the catalytic efficiency of water soluble complexes with the performance of a standard, the water insoluble complex, cis‐[Pd(CH2(CH2P(CH2CH3)2)2(NCCH3)2][BF4]2, C6, was prepared and incorporated in the investigations. The isolated alternating 1‐butene/CO copolymer exhibits glass transition temperature of Tg=−3–−15 °C, which is in the range desirable for latex emulsion application. The solid content is up to 21 % with high molecular weight (Mw=4×104 g mol−1) and narrow polydispersities (Mw/Mn=2–3). The C5 complex was found to be fourteen times more active in aqueous polymerization medium (6369 mol substr. mol Pd−1 h−1) than C6 complex in nonaqueous medium (441 mol substr. mol Pd−1 h−1). [ABSTRACT FROM AUTHOR]

Electrospun nanofiber membranes derived from polyketone (PK) are precisely fabricated to exhibit an excellent separation efficiency for oil/water emulsions. The fiber diameter and pore size of the membrane are controlled by introducing NaOH to the precursor solution prior to electrospinning. The surface properties of the nanofibers are then controlled by the removal of NaOH with water and reduction of functional groups with sodium borohydride (NaBH4) to exhibit an air‐water superhydrophilicity and underwater superoleophobicity. This surface conversion process is easily monitored by the water contact angle and the underwater oil contact angle. Oil/water emulsions, including toluene, soybean oil, and hexadecane are filtered through the membranes to examine their separation efficiency and flux using total organic carbon and UV‐Vis measurements. The optimized membrane exhibits the minimum 97 % separation efficiency for all three oil/water emulsions and recyclability without notably losing its flux under gravity‐driven filtration conditions. [ABSTRACT FROM AUTHOR]

Water electrolysis is by far the most appealing method to produce green hydrogen. Among the possible technologies, Anion Exchange Membrane (AEM) water electrolyzers are promising in the medium term, as they make it possible to avoid critical and noble materials as catalyst components. However, AEMs are still lacking in performance and stability, which has become the current research focus. Here, we report the facile and inexpensive chemical modification of polyketone (PK) with a functional unit encompassing morpholinium as the positively charged group, and the fabrication of self‐standing membranes. The synthesis products are investigated with an ensemble of physico‐chemical and spectroscopic techniques, including solid‐state and time‐domain NMR, FT‐IR, and thermal analysis. The membranes show good Ion Exchange Capacity values in the range 1.48–2.24 mmol g−1. A preliminary electrolysis test shows that the PK‐based membrane has performance comparable to that of a commercial one. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The introduction of carbonyl group with a high density in polyethylene backbone corresponds to polyketone materials, which features excellent mechanical strength, crystallinity, photodegradability, hydrophilicity, surface and barrier properties. Due to the extremely high binding affinity of carbon monoxide (CO) and kinetic preference for its subsequent insertion, the formation of nonalternating structure with extra ethylene insertion is exceptionally challenging, however, this nonalternating strategy is of significant importance for polymer modification in term of processing and solubility. Here, we have communicated our study on cationic palladium coordinated diphosphazane monoxide (PNPO) for the nonalternating copolymerization of ethylene with CO, the systematical investigation on the amine and phosphine oxide moieties in PNPO platform in term of electronic and steric modulation has been performed. It is discovered that the installation of aliphatic structure on amine moiety favors the improvement of catalyst activity and longevity, while the amino groups on phosphine oxide moiety promotes the nonalternating copolymerization. In particular, we have computationally investigated herein the aspects of the nonalternating degree by comparing with PNPO platform and 1,3‐bis(diphenylphosphanyl)propane ligands based palladium catalysts. These mechanistic studies can help to understand the catalyst structure and polyketone property relationships and shed light on future design of high‐performance copolymerization catalysts. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The introduction of carbonyl group with a high density in polyethylene backbone corresponds to polyketone materials, which features excellent mechanical strength, crystallinity, photodegradability, hydrophilicity, surface and barrier properties. Due to the extremely high binding affinity of carbon monoxide (CO) and kinetic preference for its subsequent insertion, the formation of nonalternating structure with extra ethylene insertion is exceptionally challenging, however, this nonalternating strategy is of significant importance for polymer modification in term of processing and solubility. Here, we have communicated our study on cationic palladium coordinated diphosphazane monoxide (PNPO) for the nonalternating copolymerization of ethylene with CO, the systematical investigation on the amine and phosphine oxide moieties in PNPO platform in term of electronic and steric modulation has been performed. It is discovered that the installation of aliphatic structure on amine moiety favors the improvement of catalyst activity and longevity, while the amino groups on phosphine oxide moiety promotes the nonalternating copolymerization. In particular, we have computationally investigated herein the aspects of the nonalternating degree by comparing with PNPO platform and 1,3‐bis(diphenylphosphanyl)propane ligands based palladium catalysts. These mechanistic studies can help to understand the catalyst structure and polyketone property relationships and shed light on future design of high‐performance copolymerization catalysts. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed copolymerization of CO and ethylene has a strong inherent propensity to produce the strictly alternating copolymer. In this work, nickel catalysts capable of both homopolymerization of ethylene and alternating copolymerization of CO and ethylene are developed to explore the possibility of non‐alternating copolymerization of CO and ethylene under the assumption that comonomer incorporation in the polymer chain can be adjusted by the concentrations of the comonomers. Both polyketones with slightly more than 50 % ethylene and "polyethylenes" with a small amount of CO incorporation are obtained but only under carefully controlled conditions and in low yields. [ABSTRACT FROM AUTHOR]

In this paper, the polyketone (POK) extrusion cast film is manufactured by melt stretching method, and the evolution process of the crystal morphology and mechanical properties with the increase of melt drawing ratio (MDR) are followed. The results show that the melt stretching process produces many micro shish‐kebab crystals in the POK. The length of the shish crystal and the thickness of the kebab crystal hardly increase with MDR, but the lateral length of the kebab crystal shows linear growth when MDR exceeds 40. The crystalline morphology of POK is mainly affected by melt relaxation. The molecular chain has sufficient relaxation during cooling at a low MDR (20–40). At this time, micro shish‐kebab crystals are mainly randomly arranged. When MDR exceeds 40, the rapid melt stretching shortens the relaxation time of the tie chain between the neighborhood shish crystal, and the atomic force microscopy image shows a typical shish‐kebab structure. This experimental result indicates that the formation of the oriented lamella structure may be related to the relaxation of the molecular chains between the micro‐shish. When the length of the shish axis and the thickness of the kebab lamellae are similar, it is difficult to distinguish the two. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed copolymerization of ethylene with carbon monoxide affords polyketones materials with excellent mechanical strength, photodegradability, surface and barrier properties. Unlike the widely used and rather expensive Pd catalysts, Ni‐catalyzed carbonylative polymerization is very difficult since the strong binding affinity of CO to Ni deactivates the highly electrophilic metal center easily. In this study, various cationic P,O‐coordinated Ni complexes were synthesized using the electronic modulation strategy, and the catalyst with strong electron‐donating substituents exhibits an excellent productivity of 104 g polymer (g Ni)−1, which represents a rare discovery that a Ni complex could operate with such exceptional efficiency in comparison with Pd catalysts. Notably, those Ni catalysts were also efficient for terpolymerization of ethylene, propylene with CO for producing commercial polyketone materials with low melting temperatures and easy processibility. [ABSTRACT FROM AUTHOR]

Polyketone (PK) has attracted wide attention owing to its direct utilization of carbon monoxide, excellent properties, and photodegradation performance. However, the commercialized PK is produced using Pd‐based catalysts, which accounts for the largest part of the production cost. Herein, [Ni(2‐tol)(PPh3)(N,O)] is used as the main catalyst for its high productivity and good tolerance to CO. Effects of the cocatalyst (Ni(COD)2), the aging method in CO atmosphere, and the polarity of solvent are investigated. When Ni(COD)2 is employed as the cocatalyst, the catalytic activity and molecular weight of PK are increased by 29% and 42.6%, respectively. Aging of catalyst system with Ni(COD)2 in CO atmosphere leads to significant decrease in activity and molecular weight, while aging has almost no effect on the copolymerization without Ni(COD)2. Different catalytic mechanisms are proposed for the catalyst system with and without cocatalyst. Furthermore, it is found that the polar solvent (CH2Cl2) significantly increases the activity by 119.2% compared to that in the nonpolar solvent (toluene). However, the thermal stability of the catalyst is much better in toluene. The study on the understanding of catalytic mechanism and improvement of activity will promote the practical application of nonprecious metal catalysts for preparation of PK. [ABSTRACT FROM AUTHOR]

Palladium catalysts modified with iminopyridine ligands were employed for ethylene/CO and styrene/CO copolymerization and ethylene/styrene/CO terpolymerization. Our studies revealed that the steric and electronic effects of the catalysts play key, yet distinct roles in these polymerization reactions. The thermal properties of the polyketones were engineered by varying the styrene content in terpolymers derived from ethylene, styrene, and CO sources, with increased styrene ratios yielding reduced polyketone crystallinity. [ABSTRACT FROM AUTHOR]

An isopyrazole (4H‐pyrazole)‐embedded nonane‐2,4,6,8‐tetraone derivative was synthesized as a masked‐tetraketone for stepwise and multiple functionalization. The masked‐tetraketone has six possible tautomers, but exists predominantly as a 12π‐electron conjugated keto‐enamine‐imine‐enol form, which was also observed in the solid state by single crystal X‐ray analysis. Stepwise functionalization to introduce metal‐coordination and fluorescence‐enhancement sites into the masked tetraketone furnished a fluorescent chromophore that indicates metal coordination on a microgram scale by considerably changing the solid‐state emission. [ABSTRACT FROM AUTHOR]

Metal ion adsorbents are indispensable materials for the recovery of noble metal ions in a sustainable society. Herein, we report that poly(isopyrazole-3,5-diyl-trans-vinylene) (1) effectively adsorbed group 10 metal ions from solution in acetonitrile. Owing to its fully π-conjugated and rigid structure, polyimine 1 was virtually insoluble in common organic solvents and water, making it advantageous for metal ion adsorption via a solid/liquid interface. Inductively coupled plasma (ICP) analysis showed that ≥90% of Ni2+, Pd2+, and Pt2+ ions were adsorbed at a concentration of 10 µM (order of ≤2 ppm) after stirring suspensions at room temperature. Metal ion desorption was achieved by treatment with ethylenediaminetetraacetic acid disodium salt (EDTA⋅ 2Na), and the adsorbent was reused. Theoretical calculations supported that the desolvation energy was an important factor for effective adsorption in acetonitrile. [ABSTRACT FROM AUTHOR]

Aliphatic polyketone (POK) is a new engineering plastic owning outstanding mechanics, chemical resistance, and gas/liquid barrier properties. However, analogous to other polymers, the nature of combustion severely restricts the widespread application of POK. Herein, the diethyl zinc phosphinate (ZnPi) was compounded with three grades of POKs, which were different among each other in viscosity as low (L), medium (M), and high (H) levels, by melt mixing. It is intriguing to suggest that increasing the viscosity of POK could remarkably improve the dispersion homogeneity of ZnPi, which was beneficial to superior flame retardancy, simultaneously with comprehensive mechanical properties. For the H‐POK matrix, only 10% well‐dispersed ZnPi resulted in a V0 ranking with a good maintenance of its notched impact strength, whereas the load of ZnPi for reaching V0 rank increased to 14% in L‐POKs and M‐POKs and the mechanical performances decreased mildly. By a combination of scanning electron microscopy (SEM), Fourier‐transform infrared (FTIR), thermogravimetric analysis (TGA), and cone calorimetry, it is well revealed that the flame retardancy induced by adding ZnPi could mainly ascribe to the formation of various zinc phosphate species. This work exploits a facile and feasible method for fabrication of antiflame engineering plastics, which will be promising for large‐scale applicability of high‐performance POK materials. [ABSTRACT FROM AUTHOR]

Polyketone (POK), a new environment‐friendly engineering plastic produced from carbon monoxide (CO), can be used for various applications including packaging, fibers and technical items. Due to its exceptional balance of mechanical properties and high chemical resistance, POK holds great potential to be one of the most promising candidates for high‐performance and multifunctional polymer materials. The introduction of other polymer materials, reinforcing fibers or micro‐ and/or nanofillers into the POK matrix is a powerful method for obtaining new POK‐based materials with specific characteristics and satisfactory improvements in properties. This article summarizes and highlights the recent advances and efforts in research and development in the field of POK blends, POK composites and POK blend‐based composites. The applications of POK materials and outlook are also summarized and discussed. © 2018 Society of Chemical Industry Recent advances in the field of polyketone (POK) blends, composites and blend‐based composites are summarized, and discussions of the developing directions for POK materials with specific properties are presented. [ABSTRACT FROM AUTHOR]

Abstract: Polyamide 6 and aliphatic polyketone exhibit similar melting points and heats of fusion, which expose the kinetic effects of intermolecular interactions on their crystallization kinetics. The commercial chip‐calorimeter Flash DSC1 is employed to measure their crystallization rates in a broad temperature range. The results show that polyamide crystallizes faster than polyketone at high temperatures, but slower at low temperatures. The faster crystallization is attributed to a lower lateral‐surface free energy for crystal nucleation at high temperatures on account of the sheet‐like hydrogen bonding in polyamide crystals. The slower crystallization is attributed to the lower molecular mobility for crystal nucleation at low temperatures on account of the higher glass transition temperature of polyamide. [ABSTRACT FROM AUTHOR]

The terpolymerization of CO, ethylene, and additional olefins varies the properties of polyketones depending on olefins. In this study, monomer candidates for the terpolymerization of polyketones were expanded to alkynes, in addition to olefins. Thermal properties of polyketones were modified by adding aromatic alkynes during Pd-catalyzed terpolymerization with CO and ethylene. The Tm values of terpolymers were reduced to 192-215°C. [ABSTRACT FROM AUTHOR]

ABSTRACT Few solvents are capable of dissolving polyketones (PKs). 1,1,1,3,3,3-Hexafluoro-2-propanol (hexafluoroisopropanol, HFIP) is a better solvent than trifluoroethanol and m-cresol. When HFIP was evaporated from a PK/HFIP solution, a porous cast-film with a microparticle structure was formed because the isotactic PKs adopted a helical conformation, and convection during evaporation of the high polarity and low-boiling-point HFIP caused aggregation and rolling of the polymer molecules. The addition of plasticizer suppressed particle formation, improving the surface structure and mechanical properties of the film. In particular, the dielectric properties of the film improved significantly. This will enable PKs, which are rigid insulating materials, to be used as dielectric materials, broadening their range of applications. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2014, 52, 887-892 [ABSTRACT FROM AUTHOR]

ABSTRACT The cationic polymerization of dimethylketene is achieved in dichloromethane at −30 °C, using a stoichiometric mixture of aluminum bromide (AlBr3) and tetra- n-butylammonium bromide ( n-Bu4N+Br−) as initiator. Characterizations by 1H and 13C NMR show that the resulting polymers have a perfect polyketonic microstructure. Capillary viscosity, DSC, and SEC analysis show that for a constant monomer/initiator ratio, polymers synthesized in the presence of tetra- n-butylammonium bromide are more crystalline and have better properties than those produced only with AlBr3. Melting temperatures, inherent viscosities and average molecular weights are systematically higher. A good linearity is observed between ln (inherent viscosity) versus ln [ABSTRACT FROM AUTHOR]

The coloration of different polymer films (from commodity and packaging films to performance films) by contact with various food coloring substances was evaluated. For this purpose, both solubility parameters as a prediction tool, and immersion experiments for time range between 24 and 1000 h were established. The two predicting tools are the Hoy and Hoftyzer-Van Krevelen (HVK) methods. For PE and PP, HVK's method is preferred for predicting coloration. Neither of the HVK's and Hoy's methods was able to establish a coloration prediction for PET while both methods could predict the staining of PEEK. The coloration of partially and fully fluorinated polymers is well predicted by the Hoy's method. The behavior of PP/PA and PP/PA/PP multilayer films was also studied. Crystallinity degree of polymers, temperature and concentration of coloring molecules are also important parameters, which are not taken into account in solubility theories. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

The reaction of [(domppp) Pd (OAc)2] [domppp = 1,3‐bis (di‐o‐methoxyphenylphosphino)propane] and imidazolium‐functionalized carboxylic acids containing various anions (Br−, PF6−, SbF6− and BF4−) resulted in the formation of nano‐sized Pd (II) aggregates under template‐free conditions. The rate of formation of aggregates can be modulated by changing the anion, affecting the rate of polymerization of CO and olefins without fouling. Herein, we describe the analysis of Pd (II) catalysts by dynamic light scattering, atomic force microscopy, X‐ray photoelectron spectroscopy and X‐ray crystallography, and co‐ and terpolymerization results including the catalytic activity, and bulk density and molecular weight of polymers. Various nano‐sized Pd (II) aggregates were synthesized from the Pd (II) complex and imidazolium‐functionalized carboxylic acids. The nano‐aggregates formation rate was controlled by anions of imidazolium‐functionalized carboxylic acid, and the rate and catalytic activity of Pd (II) catalysts for the polymerization of CO and ethylene were also affected by the anion in the catalytic system. [ABSTRACT FROM AUTHOR]