丙烯酸／丙烯酸羟丙酯／不饱和磺酸二元共聚物合成及阻垢性能

以丙烯酸、丙烯磺酸、磺化马来酸丙烯酰胺、２－丙烯酰胺－２－甲基丙烷磺酸、丙烯酸羟两酯为原料，过硫酸铵为引发剂制备了一系列三元共聚物，并研究了其阻垢分散性能。结果表明，按一定配比制备的共聚物对碳酸钙垢或磷酸钙垢等具有优异的阻垢分散性能。     

Properties of polyacrylonitrile and fibre based on it containing chemically active groups

Conclusions -- The properties of polyacrylonitrile and of fibres based on it, which contain high-bulk sulfonic acid groups have been investigated.-- It has been shown that upon introduction of bulky molecules into the polyacrylonitrile chain, a separation of the macromolecules takes place and the energy of interaction of the acrylonitrile groups is weakened.-- Sulfonic acid fibres have a high shrinkage, since during the process of orientation stretching, nonuniform stresses arise in them because of the content of the bulky and polar groups present in the molecular chain.Translated from Khimicheskie Volokna, No. 5, pp. 32–33, September–October, 1991.     

Pervaporation of pyridine–water mixture through poly(acrylonitrile-co-4-styrene sulfonic acid) membrane

The modified polyacrylonitrile (PAN) membranes used in this study had sulfonic acid moiety to act as a specific functional group for the dehydration of pyridine aqueous solution. The in situ complex formed between pyridine in the feed and sulfonic acid moiety in the membrane could enhance the dehydration capacity of the modified PAN membranes. It was found that the pervaporation patterns were closely related to the content of the sulfonic acid in the modified PAN membranes. The effective in situ complex membrane can be prepared by controlling the content of sulfonic acid in the membrane. The in situ complex membrane shows an increase of permeation flux with a slight decrease in separation factor as operating temperature increase. © 1996 John Wiley & Sons, Inc.     

Characterization of terpolymers containing 1,2,4‐oxadiazolic pendant groups with potential application as workover fluids

Presence of planar, bulky heterocyclic pendant groups, attached to polymer chains, alters the thermal properties and, once gelled, they modify their rheological properties as well. The authors report generation of stiff gels coming from terpolymers containing 1,2,4‐oxadiazolic pendant groups, obtained by chemical modification of commercial polyacrylonitrile. The gels formed in basic aqueous solutions were compared and the effect of substituents linked to the heterocycles on thermal stability and viscoelastic properties was also analyzed. The structural modifications were followed by FTIR. The potential use of these terpolymers as workover fluids is discussed. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Associated structures of aqueous solution of comblike polymers from 2-acrylamido-2-methyl-1-propanesulfonic acid, dodecylmethacrylate and poly(ethyleneglycol) acrylate macromonomer

Water soluble surface active comb like terpolymers consisting of 0.66:0.22:0.12m (A) and 0.37:0.52:0.11m (B) of 2-acrylamido-2-methyl-1-propane sulfonic acid (AMPS), dodecylmethacrylate (DoDMAc) and poly(ethylene glycol) monomethacrylate (PEGAc) macromonomer have been designed. The molecular weights of the polymers A and B are estimated to be 9.64×10⁴ and 9.52×10⁴. It is demonstrated that polymer A promotes intermolecular aggregated structures in contrast to polymer B favoring isolated micellar assemblies. The compact coil structures from polymer B effect considerable reduction in interfacial tension of octadecane/water interface to 14.6 mN m⁻¹.     

NaSCN二步法腈纶上色率研究

通过测定 Na SCN二步法腈纶聚合体及纺丝各工序丝束的磺酸基团含量 ,纺丝各工序丝束的序态结构及“凝胶丝束处理”工艺与上色率的相互关系 ,探讨了影响上色率波动的各种因素 ,为调控纤维上色率提供了依据。     

Mesoporous silicon sulfonic acid as a highly efficient and stable catalyst for the selective hydroamination of cyclohexene with cyclohexylamine to dicyclohexylamine in the vapor phase

In this work, a new mesoporous silicon sulfonic acid catalyst derived from silicic acid has been successfully prepared by the chemical bonding method. The physicochemical properties of mesoporous silicon sulfonic acid catalysts have been systematically characterized using various techniques. The results demonstrate that sulfonic acid groups have been grafted on silicic acid by forming a new chemical bond (Si–O–S). The mesoporous silicon sulfonic acid exhibits excellent catalytic performance and stability in the vapor phase hydroamination reaction of cyclohexene with cyclohexylamine. Cyclohexene conversion of 61% and 97% selectivity to dicyclohexylamine was maintained after running the reaction for over 350 h at 280 °C. The developed mesoporous silicon sulfonic acid catalyst shows advantages of low cost, superior acid site accessibility, and long term reactivity stability. Moreover, a possible catalytic hydroamination reaction mechanism over silicon sulfonic acid was suggested. It has been demonstrated that the sulfonic acid groups of the catalyst play an important role in the hydroamination. The present work provides a simple, efficient, and environmentally friendly method for the hydroamination of cyclohexene to valuable dicyclohexylamine, which also shows important industrial application prospects.     

聚丙烯腈/磺化聚苯醚质子交换膜的制备和性能

采用溶液共混浇铸法制备了一系列的聚丙烯腈/磺化聚苯醚(PAN/SPPO)共混质子交换膜.结果表明,磺酸基团成功引入交换膜,共混膜有较好的相容性,没产生相分离,PAN/SPPO共混膜的吸水率和溶胀率明显降低,其热性能稳定.与纯SPPO膜相比,虽然英质子传导率有所下降,但都在10-2～ 10-3S/cm数量级范围内,究全可...     

Shear rheological properties of acrylic copolymers and terpolymers suitable for potentially melt processable carbon fiber precursors

In an effort to generate melt processable polyacrylonitrile (PAN) precursor fibers suitable for conversion to carbon fibers, an acrylonitrile/methyl acrylate (AN/MA) copolymer and two acrylonitrile/methyl acrylate/acryloyl benzophenone (AN/MA/ABP) terpolymers were synthesized at molar ratios of 85/15 and 85/14/1, respectively. The termonomer (ABP) was incorporated to accelerate crosslinking via UV irradiation, which serves to prevent relaxation of orientation and flow as the temperature of the fiber is raised during thermooxidative stabilization. Two molecular weights of the terpolymer and one molecular weight of the copolymer were studied to determine the effect of the termonomer, and the effect of molecular weight (MW), on the steady shear viscosity (η) and magnitude of the complex viscosity (η*). A higher rate of increase of η as a function of time was observed for the high MW terpolymer relative to that of the copolymer over the temperature range used. Using a temperature sweep and monitoring levels of η*, a minimum was observed at lower temperatures for both terpolymers. These results suggest that copolymerization with ABP significantly increased the thermally induced kinetics of crosslinking. Comparison of the η and η* data for the low and high MW terpolymers suggested that molecular weight also significantly reduced the melt stability (increased the kinetics of crosslinking). A chemorhelogical correlation was then used to quantify the effects of the termonomer and of molecular weight on the kinetics of crosslinking of the AN terpolymers. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 2856–2865, 2004     

Terpolymers. I. The mechanical properties and transition temperatures of terpolymers of n-octadecyl acrylate,ethyl acrylate,and acrylonitrile

Earlier work revealed that the internal plasticization of polyacrylonitrile by the higher n-alkyl acrylates or N-n-alkylacrylamides yielded only brittle copolymers. This difficulty was circumvented in the present work by starting with copolymers of acrylonitrile and ethyl acrylate, over the range of compositions, and further modifying these by incrementally displacing the ethyl acrylate in each recipe by n-octadecyl acrylate through terpolymerization. In this way, the stepwise small reduction in T_g for the base ethyl acrylate–acrylonitrile copolymers was greatly increased for each of the terpolymers. Compositions were obtained ranging from glassy, brittle terpolymers, with glass transitions above room temperature, to soft plasticized polymers having sufficient polar networks retained from the nitrile to confer useful properties. The decline in the glass temperature was shown to be dependent on the free volume conferred by the side-chain methylene groups of each acrylate ester. In contrast, the decline in tensile and flexural strengths and moduli for the terpolymers having glass transitions above room temperature was produced entirely by the presence of the methylene groups of the 18-carbon ester. The glass transition region corresponded to room temperature when the acrylonitrile content of the base copolymer had been reduced to 50 mole-%. Terpolymers of this nitrile content and lower had the low moduli and large elongations of plasticized compositions. An equation was developed which correlated empirically the glass transitions and the mechanical properties with the weight fraction of the acrylate esters for the glassy terpolymers.     

Studies of the Effect of Comonomers on the Microstructure of Polyacrylonitrile in Radical Polymerization Using NMR Spectroscopy

Abstract

The free radical polymerization method has been employed to synthesize homopolymers of acrylonitrile (AN), its copolymers with methylacrylate (MA) and terpolymers containing itaconic acid (IA) in homogeneous solution (aqueous solution of sodium thiocyanate and dimethylsulfoxide media) and aqueous redox slurry system. ¹³C NMR was used to characterize these polymers in terms of steric configurations in order to study the effect of co and ter monomers on microstructure of polyarylonitrile both at low and high conversions. The study showed no significant change in microstructure of polyacrylonitrile on the introduction of MA and IA. Different techniques of polymerization for ACN-MA-IA had no effect on the microstructure of terpolymer. ¹H NMR and IR techniques were used to determine the composition of copolymers and a good agreement was observed between the results from the two techniques. The presence of unsaturated carboxylic acid monomer (IA) was confirmed by ¹H NMR.     

Analysis of sulfoxylated methyl esters (Φ-MES): Sulfonic acid composition and isomer identification

Derivatization of a C₁₂Φ-methyl ester sulfonic acid by using iodide-trifluoroacetic anhydride in dimethylformamide in a one-step reaction yielded derivatized sulfonic thiotrifluoroacetates. The latter have been analyzed by gas chromatography-mass spectrometry (MS) and liquid chromatography-MS techniques so that, for the first time, the acid composition and the mono sulfonic acid isomer distribution are shown.     

Terpolymers as precursors for CuO nanoparticles synthesis

This work describes the synthesis of terpolymers of aniline, diphenylamine, and o‐anthranilic acid (PANIDPAA) by 1 : 1 : 1 molar ratio of the respective monomers doped by different concentration of copper ions via in situ chemical terpolymerization. The results are justified by measuring spectral characteristics namely, UV‐vis absorption spectra, FTIR, and TGA. Calcining these PANIDPAA terpolymers doped by copper at temperatures in the range of 700°C led to the formation of CuO nanoparticles in the nanoscale by thermal decomposition in air directly. The stages of decompositions and the calcination temperature of the precursors have been determined from thermal analysis data sheet. The obtained CuO nanoparticles have been characterized by X‐ray diffraction and transmission electron microscope (TEM). TEM showed a particle size less than 40 nm. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41150.     

Polymers of vinylphosphonic acid,acrylonitrile, and methyl acrylate and their nanofibers

In this study, a small amount of vinylphosphonic acid was used to produce fire-retardant copolymers and terpolymers from acrylonitrile and methyl acrylate. The structures of copolymer and terpolymers were elucidated by ¹H-NMR and phosphorous analysis. Thermal decomposition of vinylphosphonic acid-containing copolymers and terpolymers started at lower temperatures than of poly(acrylonitrile-co-methyl acrylate). Methyl acrylate contributes to the thermal resistance of the terpolymers. Poly(acrylonitrile-co-methyl acrylate-co-vinylphosphonic acid) with a phosphorous content about 0.25% burned at a slower rate and emitted less smoke compared to poly(acrylonitrile-co-methyl acrylate). The burning tests showed that both copolymer and terpolymers containing vinylphosphonic acid behaved as a fire-retardant polymer. The phosphonate and phosphonic acid groups in the copolymer and terpolymers accelerate the cyclization of nitrile groups and inhibit the fire in the gas phase. Nanofibers were successfully produced by the electrospinning method from the copolymers and terpolymers containing vinylphosphonic acid moiety.     

Synthetic resin. XII. Synthesis and characterization of new terpolymer resins derived from 8‐hydroxyquinoline 5‐sulfonic acid,melamine, and formaldehyde

Terpolymers 8‐hydroxyquinoline 5‐sulphonic acid–melamine–formaldehyde (8‐HQ5‐SAMF) were synthesized through the condensation of 8‐hydroxyquinoline 5‐sulfonic acid and melamine with formaldehyde in the presence of an acid catalyst. Four different terpolymers were synthesized with various molar proportions of the reacting monomers. The terpolymer resin compositions were determined on the basis of elemental analysis. The number‐average molecular weights of these resins were determined by conductometric titration in a nonaqueous medium; viscometric measurements in dimethyl sulfoxide were carried out to ascertain the characteristic functions and constants. Ultraviolet–visible, Fourier transform infrared, ¹H‐NMR, and ¹³C‐NMR spectroscopy and thermogravimetric analysis were used to elucidate the structures. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Melting behavior of polyacrylonitrile copolymers

Summary The melting behavior of acrylonitrile copolymers, ter- and tetrapolymers was studied in the dry state and in the presence of water. The melting point depression caused by the incorporation of a specific comonomer into the polyacrylonitrile chain was shown to be dependent on the molecular structure of the comonomer. Not all comonomers gave equivalent melting point depressions on a molar basis. The Eby theory of comonomer melting was used to model the melting behavior. This theory assumes that the non-crystallizing (non-AN) comonomers enter the crystal lattice as point defects rather than being relegated to the amorphous phase. An equation was developed for predicting the melting point of copolymers, terpolymers and higher order polymers as a function of the polymer composition and the specific melting point depression constant for each comonomer. The latter constants are derived from the copolymer melting point curves. The equation is applicable to both dry and wet polymers and excellent agreement between the observed and calculated melting points for wet terpolymers and tetrapolymers was observed.     

Electrolyte‐ and pH‐responsive polyampholytes with potential as viscosity‐control agents in enhanced petroleum recovery

Low‐charge‐density amphoteric copolymers and terpolymers composed of AM, the cationic comonomer (3‐acrylamidopropyl)trimethyl ammonium chloride, and amino acid derived monomers (e.g., N‐acryloyl valine, N‐acryloyl alanine, and N‐acryloyl aspartate) have been prepared via free‐radical polymerization in aqueous media. These terpolymers with random charge distributions have been compared to terpolymers of like compositions containing the anionic comonomer sodium 3‐acrylamido‐3‐methylbutanoate. Terpolymer compositions determined by ¹³C‐ and ¹H‐NMR spectroscopy, terpolymer molecular weights and polydispersity indices obtained via size exclusion chromatography/multi‐angle laser light scattering, and hydrodynamic dimensions determined via dynamic light scattering have allowed a direct comparison of the fundamental parameters affecting the behavioral characteristics. The solution properties of low‐charge‐density amphoteric copolymers and terpolymers have been studied as functions of the solution pH, ionic strength, and polymer concentration. The low‐charge‐density terpolymers display excellent solubility in deionized water with no phase separation. The charge‐balanced terpolymers exhibit antipolyelectrolyte behavior at pH values greater than or equal to 6.5 ± 0.2. As the solution pH decreases, these charge‐balanced terpolymers become increasingly cationic because of the protonation of the anionic repeat units. The aqueous solution behavior (i.e., globule‐ to‐coil transition at the isoelectric point in the presence of salt and globule elongation with increasing charge asymmetry) of the terpolymers in the dilute regime correlates well with that predicted by the polyampholyte solution theories. An examination of the comonomer charge density, hydrogen‐bonding ability, and spacer group (e.g., the moiety separating the ionic group from the polymer chain) indicates that conformational restrictions of the sodium 3‐acrylamido‐3‐methylbutanoate and N‐acryloyl valine segments result in increased chain stiffness and higher solution viscosities in deionized water and brine solutions. On the other hand, the terpolymers with N‐acryloyl alanine and N‐acryloyl aspartate segments are more responsive to changes in the salt concentration. An assessment of the effects of the terpolymer structure on the viscosity under specified conditions of the ionic strength and pH from these studies should allow for rational design of optimized systems for enhanced petroleum recovery. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007.     

A MECHANISM FOR ENHANCING IONIC ACCESSIBILITY INTO SELECTIVE ION EXCHANGE RESINS

ABSTRACT

A bifunctional monophosphonic/sulfonic acid ion exchange resin with high capacity has been synthesized. Metal ion studies have been carried out with europium, americium, and ferric nitrate in solutions of varying acidity, with and without sodium nitrate added. The bifunctional resin complexes far higher levels of Eu(III) from 0.5 and 1 N nitric acid than the monofunctional phosphonic acid resin. It is postulated that the sulfonic acid ligand provides an access mechanism for the metal ions into the polymer matrix by hydrating the matrix and preventing its collapse in high ionic strength solutions thus allowing for rapid ionic complexation by the selective phosphonic acid ligands. The bifunctional monophosphonic/sulfonic acid resin has both ligands bound to a polystyrene support. It complexes higher levels of metal ions than a comparable resin differing only by having the monophosphonic acid ligand directly bound to the C-C backbone. Results are compared to a diphosphonic / sulfonic acid resin.     

Kinetics and thermodynamics of sulfuric acid-mediated cleavage of substituted diaryl sulfones

The cleavage of di-p-tolyl sulfone with concentrated sulfuric acid has been shown to occur at elevated temperatures (>120°C). The products were confirmed as the corresponding sulfonic acids by gas chromatography-mass spectrometry analysis of the sulfonate ester derivatives. The cleavage reactions of a series of di-p-substituted diaryl sulfones with sulfuric acid have been studied. A method using a double end-point titration has been used to quantify the amounts of sulfonic acid formed as the reactions proceed. These data have been used to construct second-order rate plots over a range of temperatures and to determine rate constants for the cleavage reactions. The second-order rate plots showed good linearity. Activation energies were determined from Arrhenius plots of the second-order rate constants over a range of temperatures. The presence of electron-donating groups decreases the activation energy of the reaction, whereas the presence of electron-with-drawing groups increases the activation energy of the reaction.     

Role of Surface Polarity in the Evolution of Polymer Surface Properties in Liquid Medium

Contact angle hysteresis of polystyrene and four modified polystyrenes, containing polar sulfonic acid and carboxylic acid groups, have been evaluated in a two-phase liquid system. Water contact angles have been measured in octane and octane contact angles have been measured in water. It has been demonstrated that wetting characteristics of polystyrene modified with sulfonic acid and carboxylic acid groups can be reversely triggered from polar in the presence of water to non-polar in the presence of octane. A contact angle hysteresis varying from 7 to 88° has been observed and a relationship between the contact angle hysteresis and the polymer surface polarity has been established. The fast kinetics of the wetting transition indicates that such polymers can permit external stimuli-induced modulation of their structures.