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1.
The current density is rather low in solid bipolar membranes, because the water transfer rate is relatively slow across solid bipolar membranes made of solid ion-exchange materials. This paper describes the use of polymer solutions, such as phosphatic poly(vinyl alcohol) solution, poly(acrylic acid) solution and poly(vinyl alcohol) solutions with dispersed cation/anion-exchange resin particles to prepare bipolar membranes. The 0. 1 mol/L NaOH and the 0.05 mol/L H2SO4 were used to test the performance of the bipolar membranes. For a fixed liquid layer thickness, both the current density and the selectivity increase with the concentration increase of a polyelectrolyte solution. The maximum current density measured in the experiment was 1497A/m^2 with a selectivity of 96.8%.  相似文献   

2.
A series of hyperbranched poly(amine-ester)polyols were synthesized by the polycondensation of N,N-diethylol-3-amine-methylpropionate(prepared by Michael addition reaction of methyl acrylate with diethanolamine)as an AB2-type monomer with trimethylol propane as the core moiety,proceeding in one-step procedure in the melt with p-toluenesulfonic acid as catalyst.The obtained monomer and polymers were characterized by FTIR and 1H-NMR spectroscopy.The solubility and surface activity in aqueous solution of the polymers were also examined.The gas permeability,water vapor permeability,and moisture absorption of microfiber synthetic leather treated by hyperbranched polymer were studied.The optimum conditions were that the dosage of dye and hyperbranched polymer was 5% and 10%,respectively.The water vapor permeability and moisture absorption of microfiber synthetic leather reached to 0.525 4 mg/(10 cm2·24 h)and 0.046 7 mg/(10 cm2·24 h).Compared with blank samples,they increased by 15% and 35%,respectively.However,the dosage of hyperbranched polymer has little influence on gas permeability of microfiber synthetic leather.SEM results show that the fiber of microfiber synthetic leather treated by hyperbranched polymer is incompact.  相似文献   

3.
1 Results A new network polymer electrolyte matrix with polyether in the side chains and main chains was synthesized by the azo-macroinitiator method and urethane reaction.The macroinitiator,polymer and network polymer were confirmed by Fourier-transform infrared (FT-IR) spectroscopy and 1H NMR.FT-IR was also used to study the environment of lithium ions doped in these network polymer electrolytes.Three important groups are considered: N-H,carbonyl,and ether groups.The thermal properties of the polymer electrolytes were measured by differential scanning calorimetry and thermogravimetric analysis.The Tg value of this polymer is less than that of a general comb-like polymer.Added lithium ions interact with the oxygen atoms on ether groups,causing the Tg of the polymer electrolyte to increase.Moreover,the interaction between lithium ions and ether groups decreases the decomposition temperature of the polymer.The conductivity measured by AC impedance reached a maximum of 10-4 S·cm-1.A plot of conductivity vs.temperature fit the Vogel-Tamman-Fulcher equation,indicating that ionic mobility in this network polymer electrolyte is coupled to segmental chain movements.  相似文献   

4.
1 Introduction Over the past decade,Dye-sensitized solar cells (DSSCs) have been intensively investigated as potential alternatives to conventional inorganic photovoltaic devices due to their low production cost and high energy conversion[1-4]. This type of solar cell has achieved an impressive energy conversion efficiency of over 10%,whose electrolyte is a voltaic organic liquid solvent containing iodide/triiodide as redox couple.However,the use of a liquid electrolyte brings difficulties in the practical application of DSSCs because of leakage and evaporation.It is well-known that ionic liquids having unique properties,such as nonvolatility,chemical and electrochemical stabilities,high ionic conductivity and gel-forming properties with polymer.Therefore,ionic liquids have attracted great attention in DSSCs due to their remarkable properties.The poly(theylene oxide) (PEO) is classical polymer matrix for solid polymer electrolyte.Based on this knowledge,our group introduced PEO-imidazole ionic liquid oligomer to electrolyte in DSSCs[2]. The gel electrolytes are also used to replace the liquid electrolytes.The gel electrolytes made from physically cross-linked gelators are unstable and have trouble in permeating into the pores of TiO2 electrodes.Our group introduced the quaternization reaction of two constituents of latent chemically cross-linked gel electrolyte precursors to overcome the permeating problem[3]. Pyridine group in organic molecules or poly(vinylpyridine) contained in the electrolyte not only can improve the open-circuit photovoltage,but also can be the reaction sites of quaternization reaction.The poly (4-vinylpyridine-co-acrylonitrile) has been synthesized and applied in the chemical gel electrolyte[4]. In this study,the copolymer of 4-vinylpyridine and oligo ethylene glycol methyl ether methacrylate was synthesized and used to form all solid state electrolyte or quasi solid state electrolyte with multifunctional halogen derivatives in DSSCs.  相似文献   

5.
Dispersed Pd nanoparticles (Pdn) have been synthesized by reducing H2PdCI4 with ethanol, and stabilized using poly(vinylpyrrolidone) (PVP). The Pdn is applied to the glassy carbon substrate to form a thin film, and then the potential cyclic scanning at 50 mV.s^-1 from -0.25 to 1.25 V was carried out for about 30 min to form the aggregations of Pdn (Pdn^ag). FTIR spectroscopy of both transmission and reflection modes was employed to study CO adsorption on Pdn and Pdn^ag in both solidlliquid and solidlgas interfaces. It has been revealed that CO adsorption on Pdn film yields two IRbands near 1964 and 1906 cm-1, which are assigned to IR absorption of CO bonded on asymmetric and symmetric bridge sites, respectively. In contrast to the IR properties of CO adsorbed on Pdn, only species of CO bonded on asymmetric bridge sites was determined on Pdn^ag, and the direction of the IR band near 1963 cm^-1 is completely inverted. The full width at half-maximum (FWHM) of the COB^as band near 1964 cm^-1 is measured to be 14 cm^-1 on Pdn film, while it is 24 cm^-1 on Pdn^ag film. The results of the present study demonstrated that the inverting of the IR band direction is a general phenomenon that is closely related to the interaction between nanoparticles in aggregation of Pdn.  相似文献   

6.
In this paper,high density polyethylene (HDPE)/poly(ethylene-co-butene) (PEB) blend (50/50 wt%) was prepared through solution blending and then compression molding,and subsequently examined by laser scanning confocal microscopy (LSCM). The PEB used in this experiment was labeled with a small quantity of a fluorescein derivative to render fluorescence. The initial films showed uniform dye dis-tribution and no indication of phase separation within the resolution of optical microscopy. Sample films annealing at 140℃ followed by rapid cooling to room temperature showed obvious phase sepa-ration and bicontinuous structure. The present work indicates that by labeling one component with fluorescein derivative,LSCM can efficiently perform in situ depth profiling of polymer blends.  相似文献   

7.
An easy hydrolysis degradable polyester (EHDP) is synthesized; the fiber produced from which can be hydrolyzed by dilute basic solution easily. The properties of these kind polyesters are measured. The results show that this kind polymer is suitable to be spun into filament The EHDP can be spun into staple fiber and manufactured into non-woven fabric. This fabric is used as disposable clothes. In composite spinning, the PET (polyethylen glycol terephthalate) or PA (poly amide) is used as continuous phase, and EHDP used as dispersed phase. Then the fabric of this kind fiber is treated by basic solution; the ultra-fine fiber fabric is obtained. The fineness of the fiber is about 0.045 dtex. In blend spinning, EHDP is mixed with polypropylene (PP) to produce hollow fiber with micro-holes hi radical direction. This fiber is a usable material in filter especially in medical use.  相似文献   

8.
Copper-cadmium halide doped photochromic glass coating on plate glass has been prepared by a sol-gel process. The sample shows reversible photochromic effect. The results of X-ray diffraction (XRD) and infrared (IR) spectrum investigations indicate that the photochromic phase of tile coating is CuBrxCl1-x, solid solution, and that the structure network of the coating is connected with the bonds of Si-O-Si, Si-O-B and Si-O-Al.  相似文献   

9.
Poly(1,1,2,2- tetrahydroperfluorodecyl acrylate) (poly (TA-N)) was synthesized in laboratory. The resulting morphology of rapid expansion of supercritical solution (RESS) sprays of poly(TA - N) was investigated. At apre - expansion temperature of 45℃), amorphous polymer was formed. At temperature around 60 ℃ to 80 ℃ , fibers were formed. Increase of temperature increasesparticle size slightly. At temperature of 105℃ , most of particles are spheres. The RESS is an attractive process. To apply the polymers desired for coating applications in an organic solvent - free process that is economically viable , and it will have implications for pollution prevention during polymer film formation  相似文献   

10.
Poly[2,2-(m-phenylene)-5,5-bibenzimidazole](mPBI)were synthesized by mixing 3,3’,4,4’-tetraaminobiphenyl and isophthalic acid in 1-butyl-3-methylimidazolium chloride([BMIM]Cl).Intrinsic viscosity of mPBI polymers was 0.67 dL/g which was measured in 96%sulfuric acid.The polymer was characterized by Fourier transform infrared spectroscopy(FTIR),nuclear magnetic resonance(1H-NMR),and thermogravimetric analysis(TGA).The effects of polymerization conditions on the intrinsic viscosity of mPBI were investigated.It showed that the molecular weight of polymer mainly depended on pre-reaction time and reaction temperature.Comparison of structure and properties of mPBI synthesized in ionic liquids(ILs)and polyphosphoric acid was also reported.It indicates that the ionic liquids are a kind of good solvents in synthesis process of mPBI and ionic liquids mainly affect molecular weight of mPBI.  相似文献   

11.
以均苯四甲酸二酐(化合物1)和L-蛋氨酸(化合物2)为反应物,无水醋酸为溶剂,反应生成酰亚胺酸[N,N'-均苯四酸-2-L-蛋氨酸二酸](化合物3).化合物3与二氯亚砜形成酰氯[N,N'-均苯四酸-2-L-蛋氨酸二酰氯](化合物4)后,在微波加热条件下,在10min内与乙二胺快速形成缩聚产物[聚N,N'-均苯四酸-2-L-蛋氨酸乙二酰胺](聚合物5).应用红外光谱分析(IR)和核磁共振氢谱分析(1H-NMR)对产物进行结构表征.结果表明,通过微波辅助加热可用L-蛋氨酸为原料将手性元素引入聚合物.  相似文献   

12.
The combination of reflectance UV-Vis spectroelectrochemistry with electrochemical quartz crystal microbalance (EQCM) and separate reflectance FTIR characterization were used to investigate the structural interconversion for poly(o.phenylenediamine) (PoPD) between its ladder structure with phenazine units and polyaniline-like linear chains. The poly(o-phenylenediamine) films potentiostatically (0.8 V vs. SCE) grew on Au electrodes from 0.20 mol·L^-1 H2SO4 (PoPD1) or 0.40 mol·L^-1 NaOH (PoPD2) aqueous solution containing 0.20 mol·L^-1 Na2SO4 + 0.10 mol·L^-1 o-phenylenediamine. By considering the mass of deposited PoPD2 film obtained from the EQCM data and the charge consumed under the current peak at ca. 0.6 V vs. SCE for oxidation of -NH2 groups in as-prepared PoPD2 during potential cycling in 0.10 mol·L^-1 aqueous H2SO4, the molar percentage of the polyaniline-like chains was estimated to be 19% (relative to total phenylenediamine units), being in agreement with the result obtained from a formaldehydecombination experiment through the aminocarbonyl reaction. After 40-cycle potential sweeps between 0.2 and 0.8 V vs. SCE the polyaniline-like chains in PoPD2 could be completely converted via intramolecular cyclization into the ladder structure with phenazine units. However, PoPD1 was found to be perfectly composed of the ladder structure with phenazine units, and after 40-cycle potential sweeps between -0.4 and 0.1 V vs. SCE only 2.5% in molar percentage of PoPD's ladder structure could be converted into polyani line-like chains, suggesting that the ladder structure with phenazine units is thermodynamically more stable due to its possessing higher conjugation.  相似文献   

13.
以9,9-二[4-(4-胺基苯氧基)苯基]呫吨(BAPX)为第3单体,将其与对苯二甲酰氯、对苯二胺(PPD)在N-甲基-2-吡咯烷酮(NMP)中进行低温溶液共缩聚反应,合成了一系列含呫吨结构的聚酰胺共聚物.研究了单体摩尔浓度、反应初始温度、第3单体用量对共聚反应的影响,并用IR、DSC、TGA等方法对共聚物进行了表征.结果表明:新型聚芳酰胺的特性粘度为1.85~3.20 dL·g-1,具有较高的玻璃化温度(305.6~325.7 ℃),在氮气氛中5%热失重温度为 524~544 ℃,800 ℃时的残炭率在52%以上.随着单体BAPX和PPD摩尔比的增加,共聚物的玻璃化温度逐渐降低,当BAPX和PPD摩尔比大于50/50时,共聚酰胺在常温下可溶于NMP、N,N-二甲基乙酰胺等极性有机溶剂中.  相似文献   

14.
以聚乙二醇作为可溶性聚合物载体,得到了聚乙二醇支载的的邻叠氮苯甲酸酯,与炔酯发生1,3-偶极环加成反应后,以KCN作为解脱剂,从聚乙二醇上解脱得到1,2,3-三唑化合物,具有较好的产率,经红外、核磁及元素分析等检测,所得数据与其结构相符.  相似文献   

15.
研究了聚(2,2,6,6-四甲基-4-羟基哌啶-1-氧基)丁二炔的合成,并经元素分析、红外光谱及电子顺磁共振波谱确定了它的结构。利用提拉样品磁强计对其磁化特征的研究表明,SIPO有明显的顺磁性而相应的聚合物-PolySIPO有一定的铁磁性,利用单体与聚合物的磁性对比研究,证明了PolySIPO的铁磁性不是无机杂质引起的。  相似文献   

16.
采用电聚合方法制成不同浓度双核磺化酞菁钴(bi-CoPc)掺杂的聚苯胺(PAn-bi-CoPc)膜,并用电化学、紫外-可见-近红外光谱、红外光谱、扫描电子显微镜及电导率进行了表征.结果表明:酞菁浓度对膜的电化学行为有影响,PAn膜和PAn-bi-CoPc膜在近红外区都有较宽的吸收带,当bi-CoPc为1 mmol/L时,PAn-bi-CoPc膜在近红外区出现明显的吸收峰,膜在近红外区的吸收强度随酞菁浓度增加而下降;红外光谱发现掺杂后酞菁的共轭体系得到加强.  相似文献   

17.
利用作者合成的N2O2杂大环双乙酸参与邻苯二胺的电化学聚合,成功地制备了性能优良的修饰电极。通过循环伏安等实验研究了电极的电化学性能。电极用于阳极溶出伏安法测定血清中的痕量铜,取得满意结果。  相似文献   

18.
以三氯化铁为氧化剂,采用一步法制备了N-乙烯吡咯的聚合物,通过红外光谱和核磁共振表征了聚合物结构,采用紫外光谱、扫描电镜和荧光光谱研究了聚合物的形貌和光致发光性.实验表明,聚合物易溶于常见的有机溶剂,可通过旋转涂膜法制备出表面均匀的棕色薄膜.荧光光谱研究表明:聚合物在四氢呋喃溶液中表现出良好的光致发光性能,以430 nm最佳波长激发时,聚合物的最大发射波长为520 nm,发绿光;当聚合物质量分数在0.007%~0.5%之间时,随溶液浓度增大,最大发射波长逐渐红移,最大荧光强度随溶液浓度提高呈现先增大后减小的变化趋势,当聚合物质量分数为0.03%时,荧光强度达到最大值.  相似文献   

19.
热致液晶聚酰胺的合成与表征   总被引:1,自引:0,他引:1  
采用低温溶液缩聚的方法,合成了一种在结构上存在着大量醚键的聚酰胺,并用红外光谱(IR)、差示扫描量热法(DSC)、偏光显微镜和扫描电子显微镜(SEM)等方法进行了表征。结果表明,该聚酰胺在熔融状态下具有明显的液晶态结构,属于典型的主链型热致液晶。  相似文献   

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