57 resultados para Solubility in waters


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A new class of high-performance materials, fluorinated poly(phenylene-co-imide)s, were prepared by Ni(0)-catalytic coupling of 2,5-dichlorobenzophenone with fluorinated dichlorophthalimide. The synthesized copolymers have high molecular weights ((M) over bar (W)= 5.74 x 10(4)-17.3 x 10(4) g center dot mol(-1)), and a combination of desirable properties such as high solubility in common organic solvent, film-forming ability, and excellent mechanical properties. The glass transition temperature (T(g)s) of the copolymers was readily tuned to be between 219 and 354 degrees C via systematic variation of the ratio of the two comonomers. The tough polymer films, obtained by casting from solution, had tensile strength, elongation at break, and tensile modulus values in the range of 66.7-266 MPa, 2.7-13.5%, and 3.13-4.09 GPa, respectively. The oxygen permeability coefficients (P-O2) and permeability selectivity of oxygen to nitrogen (P-O2/P-N2) of these copolymer membranes were in the range of 0.78-3.01 barrer [1 barrer = 10(-10) cm(3) (STP) cm/(cm(2) center dot s center dot cmHg)] and 5.09-6.2 5, respectively. Consequently, these materials have shown promise as engineering plastics and gas-separation membrane materials.

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A new class of high-performance polymers [poly(phenylene-co-naphthalimide)s] was prepared through the Ni(0) catalytic coupling of N-(4-chloro-2-trifluromethylphenyl)-5-chloro-1,8-naphthalimide and 2,5-dichlorobenzophenone. The resulting copolymers exhibited high molecular weights (high inherent viscosities) and a combination of desirable properties such as good solubility in dipolar aprotic solvents, film-forming capability, and mechanical properties. The glass-transition temperatures of the copolymers ranged from 320 to 403 degrees C and increased as the content of the naphthalimide moiety increased. Tough polymer films, obtained via casting from N-methylpyrrolidone solutions, had tensile strengths of 64-107 MPa and tensile moduli of 3.4-4.7 GPa. The gas permeability coefficients of the copolymers were measured for H-2, CO2, O-2, CH4, and N-2. They showed oxygen permeability coefficients and permeability selectivity of oxygen to nitrogen (permeability coefficient for O-2/permeability coefficient for N-2) in the ranges of 1.39-4.31 and 4.92-5.38 barrer, respectively.

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Novel bisphenol monomers (1a-d) containing phthalimide groups were synthesized by the reaction of phenolphthalein with ammonia, methylamine, aniline, and 4-tert-butylanilne, respectively. A series of cardo poly (arylene ether sulfone)s was synthesized via aromatic nucleophilic substitution of 1a-d with dichlorodiphenylsulfone, and characterized in terms of thermal, mechanical and gas transport properties to H-2, O-2, N-2, and CO2. The polymers showed high glass transition temperature in the range 230-296 degrees C, good solubility in polar solvents as well as excellent thermal stability with 5% weight loss above 410 degrees C. The most permeable membrane studied showed permeability coefficients of 1.78 barrers to O-2 and 13.80 barrers to CO2, with ideal selectivity. factors of 4.24 for O-2/N-2 pair and 28.75 for CO2/CH4 pair. Furthermore, the structure-property relationship among these cardo poly(arylene ether sulfone)s had been discussed on solubility, thermal stability, mechanical, and gas permeation properties. The results indicated that introducing 4-tert-butylphenyl group improved the gas permeability of polymers evidently.

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A series of soluble poly(amide-imide)s (PAIs) bearing triethylammonium sulfonate groups were synthesized directly using trimellitic anhydride chloride (TMAC) polycondensation with sulfonated diamine such as 2,2'-benzidinedisulfonic acid (BDSA), 4,4'-diaminodiphenyl ether-2,2'-disulfonic acid (ODADS), and nonsulfonated diamine 4,4-diaminodiphenyl methane in the presence of triethylamine. The resulting copolymers exhibited high molecular weights (high inherent viscosity), and a combination of desirable properties such as good solubility in dipolar aprotic solvents, film-forming capability, and good mechanical properties. Wide-angle X-ray diffraction revealed that the polymers were amorphous. These copolymers showed high permeability coefficients of water vapor because of the presence of the hydrophilic triethylammonium sulfonate groups. The water vapor permeability coefficients (P-w) and permselectivity coefficients of water vapor to nitrogen and methane [alpha(H2O/N-2) and (alpha(H2O/CH4)] Of the films increased with increasing the amount of the triethylammonium sulfonated groups.

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A triblock copolymer PLA-b-AP-b-PLA (PAP) of polylactide (PLA) and aniline pentamer (AP) with the unique properties of being both electroactive and biodegradable is synthesized by coupling an electroactive carboxyl-capped AP with two biodegradable bihydroxyl-capped PLAs via a condensation reaction. Three different molecule weight PAP copolymers are prepared. The PAP copolymers exhibit excellent electroactivity similar to the AP and polyaniline, which may stimulate cell proliferation and differentiation. The electrical conductivity of the PAP2 copolymer film (similar to 5 x 10(-6) S/cm) is in the semiconducting region. Transmission electron microscopic results suggest that there is microphase separation of the two block segments in the copolymer, which might contribute to the observed conductivity. The biodegradation and biocompatibility experiments in vitro prove the copolymer is biodegradable and biocompatible. Moreover, these new block copolymer shows good solubility in common organic solvents, leading to the system with excellent processibility. These biodegradable PAP copolymers with electroactive function thus possess the properties that would be potentially used as scaffold materials for neuronal or cardiovascular tissue engineering.

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A series of optically active poly(ester imide)s (PEsI's) has been synthesized by the polycondensation reactions of new axially asymmetric dianhydrides, that is, (R)-2,2'-bis(3,4-dicarboxybenzoyloxy)-1,1'-binaphthyl dianhydride and (S)-2,2'-bis(3,4-dicarboxybenzoyloxy)-1,1'-binaphthyl dianhydride, and various diamines with aromatic, semiaromatic, and aliphatic structures. The polymers have inherent viscosities of 0.45-0.70 dL/g, very good solubility in common organic solvents, glass-transition temperatures of 124-290 degreesC, and good thermal stability. Wide-angle X-ray crystallography of these polymers shows no crystal diffraction. In comparison with model compounds, an enhanced optical rotatory power has been observed for the repeat unit of optically active PEsI's based on aromatic diamines, and it has been attributed to a collaborative asymmetric perturbation of chiral 1,1'-binaphthyls along the rigid backbones.

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A novel diamine, 3,3'-bis(N-aminophthalimide) (BAPI), was prepared from 3,3'-bis(N-phenylphthalimide). Its structure was determined via IR, H-1 NMR, N-15 NMR, elemental analysis, and single-crystal X-ray diffraction analysis. A series of homo- and copolyimides were synthesized by a conventional one-step method in p-chlorophenol. The characteristic IR absorption bands of hydrazine-based imide groups were near 1780, 1750, 1350, 1100, and 730 cm(-1). The polymers showed good solubility in polar aprotic solvents and phenols at room temperature. The temperatures of 5% weight loss (T-5%) of the polyimides ranged from 495 to 530 degrees C in air. DMTA analyses indicated that the glass-transition temperatures (Tgs) of the polyimides were in the range 371-432 degrees C. These polymers had cutoff wavelengths between 350 and 400 nm. The polyimide films of 6FDA/BAPI and 4,4'-HQPDA/BAPI were colorless; other films were pale yellow or yellow.

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A new method for syntheses of hyperbranched poly(ester-amide)s from commercially available A(2) and CBx type monomers has been developed on the basis of a series of model reactions. The aliphatic and semiaromatic hyperbranched poly(ester-amide)s with multihydroxyl end groups are prepared by in situ thermal polycondensation of intermediates obtained from dicarboxylic acids (A(2)) and multihydroxyl primary amines (CBx) in N,N-dimethylformamide. Analyses of FTIR, H-1 NMR, and C-13 NMR spectra revealed the structures of the polymers obtained. The MALDI-TOF MS of the polymers indicated that cyclization side reactions occurred during polymerization. The hyperbranched poly(ester-amide) s contain configurational isomers observed by C-13 and DEPT C-13 NMR spectroscopy. The DBs of the polymers were determined to be 0.38-0.62 by H-1 NMR or quantitive C-13 NMR and DEPT 135 spectra. These polymers exhibit moderate molecular weights, with broad distributions determined by size exclusion chromatography ( SEC), and possess excellent solubility in a variety of solvents such as N, N- dimethylacetamide, dimethyl sulfoxide, tetrahydrofuran, and ethanol, and display glass-transition temperatures (T(g)s) between -2.3 and 53.2 degrees C, determined by DSC measurements.

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3,3',4,4'-Diphenylthioether dianhydride (4,4'-TDPA), 2,3,3',4'-diphenylthioether dianhydride (3,4'-TDPA), and 2,2',3,3-diphenylthioether dianhydride (3,3'TDPA) were synthesized from 3-chlorophthalic anhydride and 4-chlorophthalic anhydride. A series of polyimides derived from the isomeric diphenylthioether dianhydrides with several diamines were prepared. The properties, such as the solubility, thermal and mechanical behavior, dynamic mechanical behavior, wide-angle X-ray diffraction, and permeability to some gases, were compared among the isomeric polyimides. Both 3,3'-TDPA- and 3,4-TDPA-based polyimides had good solubility in polar aprotic solvents and phenols. The 5% weight loss temperatures of all the obtained polyimides was near 500 degrees C in nitrogen. The glass-transition temperatures decreased according to the order of the polyimides based on 3,3'-TDPA, 3,4'-TDPA, and 4,4'-TDPA. The 3,4'-TDPA-based polyimides had the best permeability and lowest permselectivity, whereas the 4,4'-TDPA-based polyimides had the highest permselectivity and the lowest permeability of the three isomers. Furthermore, the rheological properties of thermoplastic polyimide resins based on the isomeric dipbenylthioether dianhydrides were investigated, and they showed that polyimide 3,4'-TDPA/4,4-oxydianiline had the lowest melt viscosity among the isomers; this indicated that the melt processibility had been greatly improved.

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2,7-Bis(9-ethylcarbazol-3-yl)-9,9-di(2-ethylhexyl)fluorene and a segmented copolymer composed of the same chromophores alternated with hexamethylene fragments were synthesized. The obtained materials possess good solubility in common organic solvents, high thermal stability with 1% weight loss temperature of 350-370 degrees C, and suitable glass transition temperatures. Both derivatives show blue fluorescence in dilute solutions as well as in solid state, demonstrating that excimers are not formed in the thin films. The fluorescence spectra of the materials do not show any peaks in the long-wavelength region even after annealing at 200 degrees C in air. An organic LED with the configuration of ITO/copolymer/Al generates blue electroluminescence with the maximum peak at 416 nm, rather low turn-on voltage (4.0 V), and brightness of about 400 cd/m(2). The heterostructure device based on model derivative emitted stable blue light with low operation voltage (100 cd/m(2) at similar to 11 V) and demonstrated luminescence efficiency of 0.8 cd/A.

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The synthesis and characterization of hyperbranched aromatic poly(ester-imide)s are described. A variety of AB(2) monomers, N-[3- or 4-bis(4-acetoxyphenyl)toluoyl]-4-carboxyl-phthalimide and N-{3- or 4-[1,1-bis(4-acetooxyphenyl)]ethylphenyl}-4-carboxy phthalimides were prepared starting from condensation of nitrobenzaldehydes or nitroacetophenones with phenol and used for synthesis of hyperbranched poly(ester-imide)s containing terminal acetyl groups by transesterification reaction. These hyperbranched poly(ester-imide)s were produced with weight-average molecular weight of up to 6.87 g/mol. Analysis of H-1 NMR and C-13 NMR spectroscopy revealed the structure of the four hyperbranched poly(ester-imide)s. These hyperbranched poly(ester-imide)s exhibited excellent solubility in a variety of solvents such as N,N-dimethylacetamide, dimethyl sulfoxide, and tetrahydrofuran and showed glass-transition temperatures between 217 and 255 degreesC. The thermogravimetric analytic measurement revealed the decomposition temperature at 10% weight-loss temperature (T-d(10)) ranging from 365 to 416 degreesC in nitrogen.

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Two novel conjugated polyquinolines (F-PA-PQ and Cz-PA-PQ) with the phenylamine moiety as hole-transporting segment were synthesized. The resulting polyquinolines exhibited excellent thermal stabilities (Tg > 200degreesC), good solubility in common organic solvents and film-forming properties. Their optical absorption, photoluminescence, electroluminescence and sensory properties were studied.

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The extraction kinetics of ytterbium with sec-nonylphenoxy acetic acid (CA-100) in heptane have been investigated using a constant interfacial area cell with laminar flow. The influence of stirring speed and temperature on the rate indicated that the extraction rate was controlled by the experiment conditions. The plot of interfacial area on the rate showed a linear relationship. This fact together with the low solubility in water and strong surface activity of CA-100 at heptane-water interfaces made the interface the most probable locale for the chemical reactions. The influences of extractant concentration and hydrogen ion concentration on the extraction rate were investigated, and the forward and reverse rate equations for the ytterbium extraction with CA-100 were also obtained. Based on the experimental data, the apparent forward extraction rate constant was calculated. Interfacial reaction models were proposed that agree well with the rate equations obtained from experimental data.

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2,2',3,3'-Oxydiphthalic dianhydride (2,2',3,3'-ODPA) and 2,3,3',4'-ODPA were synthesized from 3-chlorophthalic anhydride with 2,3-xylenol and 3,4-xylenol, respectively. Their structures were determined via single-crystal X-ray diffraction. A series of polyimides derived from isomeric ODPAs with several diamines were prepared in dimethylacetamide (DMAc) with the conventional two-step method. Matrix-assisted laser desorption/ionization time-of-flight spectra showed that the polymerization of 2,2',3,3'-ODPA with 4,4'-oxydianiline (ODA) has a greater trend to form cyclic oligomers than that of 2,3,3',4'-ODPA. Both 2,2',3,3'-ODPA and 2,3,3',4'-ODPA based polyimides have good solubility in polar aprotic solvents such as DMAc, dimethylformamide, and N-methylpyrrolidone. The 5% weight-loss temperatures of all polyimides were obtained near 500 degreesC in air. Their glass-transition temperatures measured by dynamic mechanical thermal analysis or differential scanning calorimetry decreased according to the order of polyimides on the basis of 2,2',3,3'-ODPA, 2,3,3',4'-ODPA, and 3,3',4,4'-ODPA. The wide-angle X-ray diffraction of all polyimide films from isomeric ODPAs and ODA showed some certain extent of crystallization after stretching. Rheological properties revealed that polyimide (2,3,3',4'-ODPA/ODA) has a comparatively lower melt viscosity than its isomers, which indicated its better melt processability.

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Such physicochemical properties of sec-nonylphenoxy acetic acid (CA-100) as the solubility in water, acid dissociation constant in water, dimerization constant in heptane, and distribution constant in organic solvent-water were measured by two-phase titration. The extraction behaviors of scandium (III), yttrium (III), lanthanides (III), and divalent metal ions from hydrochloric acid solutions with CA-100 in heptane have been investigated, and the possibilities of separating scandium (yttrium) from lanthanides and divalent metal ions have been carefully discussed. The stoichiometries of the extracted metal complexes were investigated by the slope-analysis technique. The effect of the nature of diluent on the extraction of yttrium (III) with CA100 has been studied and correlated with the dielectric constant.