Facile synthesis of poly(o-phenylenediamine) microfibrils using cupric sulfate as the oxidant

A rapid, templateless, surfactantless approach is proposed to prepare microfibrils by simply mixing of aqueous cupric sulfate and o-phenylenediamine (oPD) solutions at room temperature. The as-prepared poly(o-phenylenediamine) (PoPD) microfibrils have been characterized by optical microscope, transmission electron microscope (TEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), ultraviolet-visible spectroscopy (UV-vis) and X-ray diffraction (XRD).

Properties of poly(sodium 4-styrenesulfonate)-ionic liquid composite film and its application in the determination of trace metals combined with bismuth film electrode

A new kind of bismuth film modified electrode to sensitively detect trace metal ions based on incorporating highly conductive ionic liquids 1-butyl-3-methyl-imidazolium hexafluorophosphate (BMIMPF6) in solid matrices at glassy carbon (GC) was investigated. Poly(sodium 4-styrenesulfonate) (PSS), silica, and Nafion were selected as the solid matrices. The electrochemical properties of the mixed films modified GC were evaluated. The electron transfer rate of Fe(CN)(6)(4-)/Fe(CN)(6)(3-) can be effectively improved at the PSS-BMIMPF6 modified GC.

Thermoplastic Elastomers Based on Compatibilized Poly(butylene terephthalate) Blends: Effect of Functional Groups and Dynamic Curing

Two sets of graft copolymers were prepared by grafting glycidyl methacrylate (GMA) or ally] (3-isocyanate-4-tolyl) carbamate (TAI) onto ethylene/propylene/diene terpolymer (EPDM) in an internal mixer. These graft copolymers were used as the compatibilizer to prepare the thermoplastic elastomers (TPEs) containing 50 wt%, of poly(butylene terephthalate), PBT, 30 wt% of compatibilizer, and 20 wt% of nitrile-butadiene rubber, NBR. The indirect, two-step mixer process was chosen for dynamic curing.

Preparation and Characterization of Interpenetration Polymer Network Films Based on Poly(vinyl alcohol) and Poly(acrylic acid) for Drug Delivery

A series of full interpenetrating polymer network (full-IPN) films of poly(acrylic acid) (PAA)/poly (vinyl alcohol) (PVA) were prepared by radical solution polymerization and sequential IPN technology. Attenuated total reflectance-Fourier transform infrared spectroscopy, swelling properties, mechanical properties, morphology, and glass transition temperature of the films were investigated. FTIR spectra analysis showed that new interaction hydrogen bonds between PVA and PAA were formed. Swelling property of the films in distilled water and different pH buffer solution was studied. Swelling ratio increased with increasing PAA content of IPN films in all media, and swelling ratio decreased with increasing PVA crosslink degree. Tensile strength and elongation at break related not only to the constitution of IPNs but also to the swelling ratio of IPNs.

Phase Behavior and self-assembly of poly[N-vinylformamide-co-(acrylic acid)] copolymers under highly acidic conditions

Copolymers of N-vinylformamide and acrylic acid were synthesized by conventional aqueous free-radical polymerization. The phase behavior of the copolymer solutions was investigated through the addition of hydrochloric acid and the variation of the temperature. With a moderate content of N-vinylformamide, the copolymers showed complex phase behaviors. Under low-acidity conditions, a suspending liquid was formed, whereas under high-acidity conditions, the random copolymers could assemble into round nanoparticles with a broad particle size distribution.

The first soluble conjugated poly(2,6-anthrylene): synthesis and properties

The first soluble conjugated poly(2,6-anthrylene) with 9,10-diphenyl-anthracene as the repeating unit is reported; photophysical studies reveal that this polymer represents a novel well-conjugated system.

Facile synthesis of 9,10-diarylphenanthrenes and poly(9,10-diarylphenanthrene)s

One-pot reduction of 9,10-diaryl-9,10-dihydrophenanthrene-9,10-diols to 9,10-diarylphenanthrenes was achieved with Zn/H+ in acetic acid. Accordingly, various novel phenanthrenes and polyphenanthrenes with efficient blue emission were easily synthesized.

Study on the Cell Structure and Compressive Behavior of Biodegradable Poly(epsilon-caprolactone) Foam

Biodegradable poly(e-caprolactone) (PCL) foams with a series of controlled structures were prepared by using chemical foaming method. The cell morphology was detected by scanning electron microscope (SEM). The compressive behavior of the foams was investigated by uniaxial compression test. The effect of density and structural parameters on the foam compressive behavior was analyzed. It was found that the relative compressive modulus has a power law relationship with relative density. Increasing of both the cell wall thickness and the cell density lead to higher compressive modulus of the foam; however, the cell size has no distinct effect on compressive behavior.

Time-resolved synchrotron SAXS observations on sheared syndiotactic poly(propylene) crystallization process

The in situ crystallization kinetics of syndiotactic poly(propylene) (sPP) has been investigated by synchrotron small-angle X-ray scattering (SAXS). The structure evolutions during the isothermal crystallization of sPP with different shear rates have been observed. The results show that shear accelerates the process of crystallization kinetics. Even under low shear rate, the lamellae can be distinctly oriented. In contrast, the lamellar parameters such as the long period, lamellar thickness, and the scattering invariant 0 can change obviously only under high shear rate.

Crystallization and morphology of poly(ethylene oxide-b-lactide) crystalline-crystalline diblock copolymers

The crystallization behaviors and morphology of asymmetric crystalline-crystalline diblock copolymers poly(ethylene oxide-lactide) (PEO-b-PLLA) were investigated using differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD), and microscopic techniques (polarized optical microscopy (POM) and atomic force microscopy (AFM)). Both blocks of PEO5-b-PLLA(16) can be crystallized, which was confirmed by WAXD, while PEO block in PEO5-b-PLLA(30) is difficult to crystallize because of the confinement induced by the high glass transition temperature and crystallization of PLLA block with the microphase separation of the block copolymer.

Synthesis and properties of sulfonated poly[bis(benzimidazobenzisoquinolinones)] as hydrolytically and thermooxidatively stable proton conducting ionomers

Novel sulfonated poly [bis(benzimidazobenzisoquinolinones)] as hydrolytically and thermooxidatively stable electrolyte for high -temperature fuel cell applications are reported. A series of sulfonated polymers (SPBIBI-x, x refers to molar percentage of sulfonated dianhydride monomer) were synthesized from 6,6'-disulfonic-4,4'-binaphthyl-1,1',8,8'-tetracarboxylic dianhydride (SBTDA), 4,4-binaphthyl-1,1,8,8-tetracarboxylic dianhydride (BTDA), and 3,3'-diaminobenzidine. The chemical structures of those polymers as well as model compounds synthesized from SBTDA and o-phenylenediamine were confirmed by nuclear magnetic resonance (NMR) and Fourier transform infrared (FTIR).

Synthesis of sulfonated poly(arylene-co-naphthalimide)s as novel polymers for proton exchange membranes

A series of novel sulfonated poly(arylene-co-binaphthalimide)s (SPPIs) were successfully synthesized via Ni(0) catalytic coupling of sodium 3-(2,5-dichlorobenzoyl)benzenesulfonate and bis(chloronaphthalimide)s. Bis(chloronaphthalimide)s were conveniently prepared from 5-chloro-1,8-naphthalic anhydride and various diamines. Tough and transparent SPPI membranes were prepared and the electrolyte properties of the copolymers were intensively investigated as were the effects of different diamine structures on the copolymer characterisitics. The copolymer membrane Ia-80, with an ion exchange capacity (IEC) of 2.50 meq g(-1), displayed a higher proton conductivity, i.e. 0.135 S cm(-1) at 20 degrees C, as compared to Nafion 117 (0.09 S cm(-1), 20 degrees C).

Synthesis of isomeric bis(amine anhydride)s for novel poly(amine imide)s by Pd-catalyzed amination of 4-chlorophthalic anhydride

Two novel bis(amine anhydride) monomers, N,N'-bis(3,4-dicarboxyphenyl)-1,4-phenylenediamine dianhydride I and N,/N'-bis(3,4-dicarboxyphenyl)-1,3-phenylenediamine dianhydride 11, were prepared via palladium-catalyzed amination reaction of 4-chloro-N-methylphthaliniide with 1,4-phenylenediamine or 1,3-phenylenediamine, followed by alkaline hydrolysis of the intermediate bis(amine imide)s and subsequent dehydration of the resulting tetraacids. A series of new poly(amine imide)s were prepared from the synthesized dianhydride monomers with various diamines in NMP via conventional two-step method.

Novel thin-film composite membranes with improved water flux from sulfonated cardo poly(arylene ether sulfone) bearing pendant amino groups

A new class of polymeric amine, namely, sulfonated cardo poly(arylene ether sulfone) (SPES-NH2) was synthesized and used for the preparation of thin-film composite membrane. The TFC membranes were prepared on a polysulfone supporting film through interfacial polymerization with trimesoyl chloride (TMC) solutions and amine solutions containing SPES-NH2 and m-phenylenediamine (MPDA). The resultant membranes were characterized with water permeation performance, chemical structure, hydrophilicity of active layer and membrane morphology including top surface and cross-section.

Sulfonated poly(arylene-co-imide)s as water stable proton exchange membrane materials for fuel cells

A novel sulfonated poly(arylene-co-imide)s were synthesized by Ni(0) catalytic copolymerization of sodium 3-(2,5-dichlorobenzoyl)benzenesulfonate and naphthalimide dichloride monomer. The synthesized copolymers with the - SO3H group on the side-chain of polymers possessed high molecular weights revealed by their high viscosity and the formation of tough and flexible membranes. Because of the introduction of electron donating phenoxy groups into naphthalimide moieties, the hydrolysis of the imide rings was depressed. The resulting copolymers exhibited excellent water stability. The copolymer membranes display no apparently change in appearance, flexibility, and toughness after a soaking treatment in pressurized water at 140 degrees C for 250 h.