A Selection of Alkali and Alkaline Earth Metal Salts of 5,5′‐Bis(1‐hydroxytetrazole) in Pyrotechnic Compositions

The dilithium ( 1 ), disodium ( 2 ), dipotassium ( 3 ) and dicesium ( 4 ) salt as well as the calcium ( 5 ), strontium ( 6 ) and barium ( 7 ) salt of 5,5′‐bis(1‐hydroxytetrazole) were prepared and characterized including NMR‐, IR‐ and Raman spectroscopy, mass spectrometry, elemental analysis and differential scanning calorimetry. The crystal structures of 1 , 2 and 4 – 6 were additionally determined by single‐crystal X‐ray diffraction. The sensitivities of the salts towards impact, friction and electrostatic discharge were determined by means of BAM (Bundesanstalt für Materialforschung‐ und prüfung) methods. The potential use of 1 , 6 and 7 as coloring agents in pyrotechnical mixtures as well as the utilization of 3 and 4 as additives in near infrared (NIR) emitting pyrotechnical formulations was examined.     

均相沉淀法制备不同晶形碳酸钡的研究

以八水氢氧化钡和尿素为原料,采用均相沉淀法制备了碳酸钡粉体。通过添加合适的晶形控制剂,合成了线状、针状和柱状等不同晶形的碳酸钡粉体,通过扫描电子显微镜(SEM)和X射线衍射仪(XRD)进行了表征,结果表明:当晶形控制剂用量为0. 3% (控制剂与氢氧化钡的质量比)左右时,合成的碳酸钡粉体分散性良好,粒度较小,形貌完整。同时对不同晶形碳酸钡的形成机理进行了初步的探讨。     

Electric-field-sensitive polymers: Reversible bending of rod-shaped polymer gels in salt solutions

Neutral gel (acrylamide [AAm] gel) and anionic gel (copolymer gel of 2-acrylamido-2-methyl-1-propane sulfonic acid [AMPSA] and butyl methacrylate [BMA]) were prepared to observe the bending phenomena in various salt solutions. The bending pattern of AAm gel was closely related to salts used in the aqueous media. The competition NMR technique was used to understand the interaction of salts with the polymer matrix. In the case of copolymer gel, the bending pattern did not show the salt dependence and the bending angle decreased after reaching a maximum. © 1994 John Wiley & Sons, Inc.     

Dispersion polymerization of acrylamide with 2‐acrylamido‐2‐methyl‐1‐propane sulfonate in aqueous solution

The copolymer of acrylamide (AM) and 2‐acrylamido‐2‐methyl‐1‐propane sulfonate (AMPS) was synthesized through the free radical dispersion polymerization in an aqueous solution of ammonium sulfate and in the presence of poly(2‐acrylamido‐2‐methyl‐1‐propane sulfonate) as stabilizer. The average particle size of the copolymer ranged from 1 to 4 μm, and the molecular weight was from 2.0 × 10⁶ to 7.0 × 10⁶ g mol^?1. By analyzing apparent viscosity and particle size, the swelling property of the dispersion copolymer was studied. When the dispersion was diluted with salt water in which the ammonium sulfate concentration kept equal with that of the original dispersion, particle size and particle size distribution of the diluted dispersion changed a little, compared with that of the original dispersion. While diluted with deionized water, particle size and particle size distribution could expand several times. The effects of varying concentrations of the stabilizer, the monomer, the salt and the initiator on particle size, and molecular weight of the copolymer were investigated, respectively. The reaction conditions for preparing stable dispersion were concentrations of 20–28% of the salt, 6–14% of monomers, and 1.8–2.7% of the stabilizer. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102:2379–2385, 2006     

Barium Sulfate Crystallization Kinetics in the Used Quenching Salts Treatment Process

The research results and kinetic studies on the barium ions precipitation process by means of crystalline ammonium sulfate addition are presented. The influence of: barium, sodium, potassium and calcium chlorides concentration in the feeding solution and also the process temperature on barium sulfate mass crystallization kinetics are investigated. Experiments were carried out in the MSMPR crystallizer with internal circulation of suspension. The barium sulfate nucleation and crystal growth rates were estimated from crystal size distribution taking into account a size dependent growth (SDG). Research results may be utilized in the used quenching salts processing technology.     

Synthesis and Energetic Properties of 4,4′,5,5′‐Tetranitro‐2,2′‐biimidazolate(N4BIM) Salts

This paper describes the synthesis and characterization of several salts of 4,4′,5,5′‐tetranitro‐2,2′‐biimidazolate (N4BIM). Each of the salts were characterized chemically, thermally, morphologically, as well as with respect to destructive stimuli (impact, electrostatic discharge, friction, thermal). These salts show promise as propellant ingredient additives, and in particular, the bis‐triaminoguanidinium salt of N4BIM displays excellent burn rate and combustion behavior. Our combustion studies have shown that TAGN4BIM displays a fast burning rate and has the lowest pressure dependence exponent yet measured for a triaminoguanidinium salt.     

P（AMPS-DMAM）共聚物钻井液降滤失剂的合成

采用氧化-还原引发体系,以2-丙烯酰氨基-2-甲基丙磺酸、N,N-二甲基丙烯酰胺为原料,通过均匀设计优化,合成了P（AMPS/DMAM）共聚物钻井液降滤失剂,借助红外光谱对聚合物进行了结构表征,初步评价了共聚物的钻井液性能。结果表明,P（AMPS/DMAM）共聚物作为钻井液处理剂,热稳定性好,抗温能力强,在淡水、盐水和饱和盐水钻井液中均具有较好的降滤失作用,经过220℃高温老化后仍能较好地控制钻井液的滤失量。     

Effect of salt species on characterization of Bi3NbTiO9 powders prepared by molten salt method

The carbonates, chloride and sulphate salts were chosen as fluxes to synthesize Bi₃NbTiO₉ (BNTO) powders at low temperature by the molten salt synthesis (MSS) method and the influence of salt species on the formation and powder characteristics of BNTO was investigated in this paper. The results showed that for the sulphate flux the formed particle size was the largest among all the used salts, but the fastest particle growth rate was found in the carbonates flux. Investigations on morphology characteristics of powders showed the plate-like powders with smaller particle size were synthesized in the chloride flux, but the powders obtained in the sulphate flux were shown to be irregular blocks in shape. Further studies indicated the salt content had a strong influence on crystallization of BNTO from the chloride flux.     

Solution properties of ionic hydrophobically associating polyacrylamide with an arylalkyl group

Copolymers of acrylamide, 2‐acrylamide‐2‐methylpropanesulfate (AMPS), and hydrophobic monomer N‐arylalkylacrylamide (BAAM) were synthesized by free‐radical micellar copolymerization. The effects of the copolymer, BAAM, AMPS, and NaCl concentrations and the pH value on the apparent viscosity of the copolymers were studied. The solution viscosities increased sharply when the copolymer concentration was higher than the critical associating concentration. The apparent viscosities of aqueous solutions of poly(N‐arylalkylacrylamide‐co‐acrylamide‐co‐2‐acrylamide‐2‐methylpropanesulfate) (PBAMS) increased with increasing BAAM and AMPS concentrations. PBAMS exhibited good salt resistance. With increasing pH, the apparent viscosities first increased and then decreased. Dilute PBAMS solutions exhibited Newtonian behavior, whereas semidilute aqueous and salt solutions exhibited shear‐thickening behavior at a lower shear rate and pseudoplastic behavior at a higher rate. Upon the removal of shear, the aqueous solution viscosities recovered and became even greater than the original viscosity, but the salt solution viscosities could not recover instantaneously. The elastic properties of PBAMS solutions were more dominant than the viscous properties, and this suggested a significant buildup of a network structure. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 316–321, 2005     

Low‐temperature preparation of titanium diboride fine powder via magnesiothermic reduction in molten salt

Phase pure titanium diboride (TiB₂) powder of 100‐200 nm was synthesized from TiO₂ and B₂O₃ using a molten‐salt‐assisted magnesiothermic reduction technique. The effects of salt type, Mg amount, reaction temperature, and TiO₂ raw materials on the synthesis process were examined and the relevant reaction mechanisms discussed. Among the three chloride salts (NaCl, KCl, and MgCl₂), MgCl₂ showed the best accelerating‐effect. To synthesize phase pure TiB₂, 20 mol% excessive Mg had to be used to compensate for the evaporation loss of Mg. Particle shape and size of raw material TiO₂ showed little effect on the formation of TiB₂ and its shape and size, suggesting that relatively cheaper and coarser TiO₂ raw materials could be used for low‐temperature synthesis of TiB₂ fine particles. The “dissolution‐precipitation” mechanism governed the overall molten salt synthesis process.     

Microfluidic Synthesis of Size‐Controlled and Morphologically Homogeneous Lead Trinitroresorcinate Produced by Segmented Flow

Size‐controlled and morphologically homogeneous lead trinitroresorcinate (LTNR) particles were synthesized in aqueous solutions using segmented flow. The experimental setup consisted of syringe pumps connected with silicone tubing to a segmented flow microfluidic platform made of polymethyl methacrylate (PMMA) containing silicone‐based microchannels immersed in a thermostatted bath. As a starting point for the optimization of the experimental conditions, LTNR particles were first synthesized through conventional batch synthesis. The optimized batch conditions were adapted to segmented flow arrangements. Characterization studies on LTNR formed through batch and segmented flow methods were carried out, and it was found that in the latter LTNR particles exhibited superior particle morphology and narrower particle size distribution. In addition, the heat release of LTNR prepared by segmented flow increased by 353.52 J g⁻¹ in comparison to that formed through batch synthesis. Finally, it was found demonstrated that segmented flow methods result in a 13 % increase in yield for the synthesis of LTNR. This study demonstrated the feasibility of synthesising primary explosives using a segmented flow microfluidic platform.     

Ionic salt permeability through phase‐separated membranes composed of amphoteric polymers

Amphoteric copolymers composed of hydrophilic poly(dimethyl acrylamide) and hydrophobic poly(dimethyl siloxane) formed phase‐separated membranes. The hydrophilic and hydrophobic components formed continuous phase‐separated domains in the membranes. The hydrated poly(dimethyl acrylamide) domains formed membrane‐spanning pathways, which permitted an ionic salt to permeate the membranes. The permeability of the ionic salt through the amphoteric copolymer membranes was studied. On the basis of the results, the mechanism of salt transport could be explained by the free‐volume theory, which was used for the analysis of diffusive transport in the hydrated, homogeneous membranes. The diffusion coefficient of the ionic salt increased exponentially as the volume ratio of the hydrophilic polymer to water [(1 − H)/H, where H is the degree of hydration] decreased in the membrane. It was possible to postulate that the diffusion of the ionic salt through the membranes was dependent on the free‐volume fractions of water and hydrophilic poly(dimethyl acrylamide) domains in the membranes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Solution behavior of water‐soluble poly(acrylamide‐co‐sulfobetaine) with intensive antisalt performance as an enhanced oil‐recovery chemical

In the process of oilfield development, salt tolerance is an important property for enhanced oil‐recovery (EOR) chemicals. In this study, we synthesized two acrylamide‐based sulfobetaine copolymers containing 2‐hydroxy‐3‐[(3‐methacrylamidopropyl)dimethylammonio]propane sulfonate (SHPP) or 3‐(4‐acry‐loyl‐1‐methyl‐piperazinio)‐2‐hydroxypropane sulfonate (SHMP). The interactions between these two copolymers and inorganic salts were compared, and the apparent viscosity (η_app) behaviors of copolymer–salt solutions at different shear rates and temperatures were investigated. We found that the η_app of PAPP and PAMP showed intensive antisalt performance, exhibiting an excellent antipolyelectrolyte effect. The η_app retention value of 30,000 mg/L PAMP in brine was 86.47 mPa s at 510 s^?1, and when the temperature was increased to 90 °C, it was 99.73 mPa s; this was better than that of PAPP under the same conditions. Therefore, PAMP was more applicable as an EOR chemical that have outstanding salt tolerance and temperature resistance. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46235     

抗钙钻井液降滤失剂P(AMPS-DEAM)聚合物的合成

采用氧化-还原引发体系,以N,N-二乙基丙烯酰胺和2-丙烯酰基-2-甲基丙磺酸为原料,合成了P(AMPS-DEAM)共聚物抗高温抗钙钻井液降滤失剂。通过正交实验优化了配方及合成条件:m(DEAM):m(AMPS)=0.9:1、反应温度40℃、单体质量分数25%、引发剂用量0.22%,用红外光谱对聚合物的结构进行了表征,初步评价了共聚物的钻井液性能。结果表明,P(AMPS-DEAM)共聚物热稳定性好,作为钻井液处理剂,在淡水、盐水、饱和盐水和CaCl_2钻井液中均具有较好的降滤失作用。经过180℃超高温老化后仍能较好地控制钻井液的滤失量,体现出了良好的抗温、抗盐和抗钙性能。     

Synthesis of copolymer of aniline and pyrrole by inverted emulsion polymerization method for supercapacitor

Copolymer of aniline and pyrrole was synthesized by inverted emulsion polymerization method by oxidizing aniline and pyrrole using benzoyl peroxide in presence of sodium laurylsulphate surfactant and p‐toluenesulphonic acid. Copolymer samples were characterized by infrared, X‐ray diffraction and scanning electron microscopic techniques and compared their properties with the corresponding homopolymers. The optimum reaction conditions for the preparation of copolymer with reasonably good yield (1.72 g) and conductivity (7.3 × 10^?2 S/cm) were established. The synthesis procedure was extended to prepare copolymer samples using various protonic acids. Electrochemical characterization such as cyclic voltammetry, charge‐discharge and impedance were carried out on symmetrical supercapacitor cell consists of poly(aniline‐co‐pyrrole)‐p‐toluenesulfonic acid salt, wherein, the copolymer salt was synthesized using equal amount of aniline and pyrrole monomers. The values of specific capacitance, energy and power densities for poly(aniline‐co‐pyrrole)‐p‐toluenesulfonic acid system (PANI‐PPy) were calculated from charge‐discharge studies and are found to be 21 F/g, 5.7 Wh/Kg and 100 W/Kg respectively. Impedance analysis showed specific capacitance value (57 F/g) at 0.01 Hz at 0.22 V. Among the copolymer salts, copolymer prepared with sulfuric acid showed higher capacitance (66 F/g). © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Dispersion Properties of BaTiO3 Colloids with Amphoteric Polyelectrolytes

An amphoteric water-soluble copolymer, i.e., poly(acrylamide/(α- N,N -dimethyl- N -acryloyloxyethyl) ammonium ethanate) (PAAM/DAAE), was evaluated as a novel dispersant for aqueous BaTiO₃ (BT) slurries. The dispersing property of this copolymer was examined by means of rheology, sedimentation, particle size, green density, zeta potential, and leached Ba²⁺ concentration measurements. The results indicate that PAAM/DAAE could reduce the viscosity of slurries greatly, cause BT particle sizes to shift to smaller values, and make green compacts more consolidated. Compared with a commercial dispersant, ammonium salt of poly(methacrylic acid) (PMAA-NH₄), it is as effective or even better in preparing stabilized suspensions. More importantly, PAAM/DAAE could lessen the leached Ba²⁺ concentration. This is related to the adsorption behavior of this copolymer onto BT particles, and the interaction between the adsorbed dispersant and dissolved barium ions.     

Synthesis and Energetic Properties of Imidazolium and 2‐Methylimidazolium Salts of 3‐Nitro‐1,2,4‐Triazol‐5‐One

Two new energetic salts of 3‐nitro‐1,2,4‐triazol‐5‐one (NTO) were described. Imidazole and 2‐methylimidazole salt of NTO decomposes exothermically at 217 and 258 °C respectively. Detonation parameters calculated for 2‐methylimidazole salt are significantly smaller than that of 2,4,6‐trinitrotoluene (TNT) but these parameters estimated for imidazole salt are comparable with that of TNT. Structure of new compounds were investigated with NMR and IR spectroscopy. Impact and friction sensitivity determined for new compounds are smaller than for pure NTO, so they are more safe during handling.     

Water-soluble copolymers. XI. Selectivity in the graft copolymerization of acrylamide/N-(1,1-dimethyl-3-oxybutyl)acrylamide comonomers onto dextran by Ce(IV)-induced initiation

Characteristic behavior in the graft copolymerization of acrylamide/N-(1,1-dimethyl-3-oxybutyl)acrylamide (AM/DAAM) comonomers onto dextran by Ce(IV)-induced initiation was investigated. From a preliminary study, it was found that ceric ammonium nitrate polymerized AM/DAAM comonomer mixtures and diacetone acrylamide, but not acrylamide alone in the aqueous solution. The effect of grafting conditions on the graft copolymerization product was studied with the aid of aqueous size exclusion chromatography and the anthrone reagent. The selectivity of formation of the graft copolymer over random copolymer was found to increase as the reaction temperature and AM/DAAM ratio increased and as both the Ce(IV)/Dextran molar ratio and HNO₃ concentration decreased. After establishing optimum grafting conditions, graft copolymer samples were prepared, and their aqueous solution behavior studied as functions of structure, temperature, and added salts.     

Synthesis and properties of cationic polyacrylamide containing pyridine quaternary salt

The copolymer P(AM‐co‐4VP) of acrylamide (AM) and 4‐vinylpyridine (4VP) was synthesized by radical copolymerization in solution, and then the copolymer was quaternarized using dimethyl sulfate to produce cationic P(AM‐co‐4VP) (CPAV), a cationic polyacrylamide containing quaternary pyridine salt. Two series of CPAV have been synthesized. The structure and composition of the copolymer and the cationic copolymer were characterized by their FTIR, ¹H NMR and ultraviolet spectra Flocculation and corrosion inhibition properties of the cationic copolymer were studied in detail and effects of cationic degree and molecular weight on the flocculation and corrosion inhibition properties were discussed. The results showed that cationic polyacrylamide containing quaternary pyridine salt possesses excellent flocculation, corrosion inhibition and other functions. The higher the degree of cationization, the better are these functions, and the molecular weight also effects the functions significantly. Copyright © 2003 Society of Chemical Industry     

Synthesis and characterization of an associative polymer with an octylphenyl polyoxyethylene side chain as a potential enhanced‐oil‐recovery chemical

A novel nonionic surfmer, AGE‐TX‐100, was synthesized by the epoxide ring‐opening reaction of allyl glycidyl ether and polyoxyethylene (10) octylphenyl ether (TX‐100). Then a novel copolymer, acrylamide (AM)/acrylic acid (AA)/AGE‐TX‐100, was synthesized with AM, AA, and AGE‐TX‐100 in aqueous solution through free‐radical random polymerization. The structures of the novel surfmer and copolymer were characterized by IR and ¹H‐NMR. The results of the salt‐resistance tests and the rheological tests indicate that the copolymer had good salt tolerance, thermal stability at high temperatures, and shearing resistance under high shear rates. The environmental scanning electron micrographs showed that the copolymer could form a tighter three‐dimensional network structure than partially hydrolyzed polyacrylamide (HPAM) in aqueous solution. Compared with the HPAM solution, the copolymer solution showed a good ability to emulsify organic components. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41024.