PEI交联的PECH/nylon复合阴离子交换膜的制备及性能研究

聚环氧氯丙烷(PECH)是一种线性高分子聚合物,具有较好的稳定性和成膜性能,且以PECH为基体制备阴离子交换膜,可避免致癌物质如氯甲醚、双氯甲醚的使用,但存在机械强度差与吸水性较大等缺点。本研究采用聚乙烯亚胺(PEI)作为交联剂,通过其与PECH发生交联反应,在其内部形成网状结构限制PECH膜在水中的过度溶胀,从而增强膜的机械强度,同时引入尼龙网布(nylon)作为支撑材料进一步提高膜的力学性能,制备了QCPECH/nylon复合阴离子交换膜。研究结果表明,制备的P1膜在电渗析应用过程中的脱盐效率(94.8%)比商业膜(Neosepta AMX)的脱盐效率(92.4%)更高,由此可见,用PEI交联的PECH/nylon复合阴离子交换膜在电渗析脱盐中具有潜在的发展前景。     

壳聚糖/壳聚糖季铵盐交联共混阴离子交换膜的制备与性能研究

制备了一种新型阴离子交换膜——壳聚糖/壳聚糖季铵盐交联共混膜,并用FTIR对共混膜进行了初步表征;分析研究了不同交联度及配比对离子交换膜相关性能的影响;并运用测试膜电位的方法估算了离子的迁移数和选择透过度。研究表明,膜呈现较好的电化学性能,而膜的力学性能较差、含水量高、选择透过度稍低。HACC含量为25%,交联度为0.2%的共混膜干强与湿强分别为53.10 MPa和8.40 MPa,含水量66.4%,IEC为1.97 mmol/g,面电阻2.67Ω.cm2,离子迁移数为0.91,选择透过度为81.6%。     

富勒烯交联季铵化聚苯醚阴离子交换膜的制备

通过富勒烯C₆₀与乙二胺合成立体纳米分子C₆₀(EDA)₈,并以此为交联剂与三阳离子功能化聚苯醚制备了一系列交联型阴离子交换膜。C₆₀(EDA)₈中立体纳米结构有效地支撑了高分子链段,构建了更发达的离子通道,有效地提升了电导率。实验结果表明,随着C₆₀(EDA)₈加入量增加,交联膜的离子交换容量减小,而电导率却逐渐增加。当交联剂C₆₀(EDA)₈加入量为5%时,电导率提高了34%。此外,所制备的离子交换膜均表现出良好的抗溶胀能力、力学性能与耐碱性。     

聚苯并咪唑/改性聚环氧氯丙烷阴离子交换膜的性能

通过缩聚法制备了含氟聚苯并咪唑(FPBI),以1–甲基咪唑和聚环氧氯丙烷为原料,制备了咪唑盐修饰的聚环氧氯丙烷(Im PECH),并通过溶液浇铸法制备了FPBI/Im PECH复合膜。系统地研究了复合膜中Im PECH含量的不同对复合膜的力学性能、热稳定性、离子电导率、离子交换容量(IEC)、吸水率、溶胀度等性能的影响。研究结果表明,随着Im PECH含量的增加,复合膜的吸水率、溶胀度、IEC、离子电导率逐渐增加,依然能够保持良好的力学性能和热稳定性。FPBI/Im PECH复合膜在80℃下最高电导率达到55.74 m S/cm,并展示了优异的耐碱性,该复合阴离子交换膜有望在碱性阴离子交换膜燃料电池中得到应用。     

不同侧链BPPO阴离子交换膜的制备及其抗污染性能

采用含有不同碳链长度的4-乙基吡啶、3-丁基吡啶与3-己基吡啶,通过亲核取代反应分别对溴化聚苯醚（BPPO）进行季铵化,制得三种阴离子交换膜（QBPPO-1、QBPPO-2、QBPPO-3）并对其电化学性能、脱盐性能以及抗污染性能进行了研究。实验结果表明随着吡啶环上烷基碳链的增长,制得的离子交换膜的离子交换容量呈现下降趋势,由1.92 mmol/g降至1.34 mmol/g,而膜面电阻逐渐增加,由2.99 Ω·cm²增加到10.59 Ω·cm²;在电渗析实验中,与商业日本Fuji阴离子交换膜相比,本实验制备的三种离子交换膜均呈现出较高的脱盐率;在污染实验中,随着高分子骨架侧链碳链的增长,离子交换膜在污染实验中的的转折时间逐渐变短,抗污染能力下降;计算模拟结果表明疏水作用在有机污染物（十二烷基苯磺酸钠）与离子交换膜内高分子骨架侧链的亲和相互作用中占有重要地位。     

氟化聚芳醚/PVDF复合阴离子交换膜的制备

为制备导电性能和机械性能良好的阴离子交换膜,将五甲基胍功能化的氟化聚芳醚二唑(FPAEO-G)与聚偏氟乙烯(PVDF)进行溶液共混制备了FPAEO-G/PVDF复合离子交换膜。考察了PVDF比例对复合膜的溶胀率、吸水率、离子交换容量(IEC)以及电导率等性能的影响。测试结果表明,PVDF共混比例为10%时,复合膜在室温(20℃)下的溶胀率为10.93%,吸水率是42.98%,离子交换容量(IEC)为1.54mmol/g,电导率为1.37×10-2S/cm。     

阴离子交换膜改性及抗污染性能研究进展

电渗析技术应用于工业废水脱盐时,废水中有机物及其它杂质组分等会造成膜污染,进而影响脱盐性能。电渗析膜污染防治对促进电渗析在工业废水处理中的应用有重要意义。相比于阳离子交换膜,阴离子交换膜更易形成有机污染,且更严重。阴离子交换膜污染主要由腐殖酸、牛血清蛋白、阴离子表面活性剂等有机物造成,污染过程主要受静电作用、亲和作用和几何因素的影响。膜改性提高阴离子交换膜的抗污染性能是电渗析膜污染防治的有效方法,目前已有许多有关膜改性提高阴离子交换膜抗污染性能的报道。膜改性方法主要有化学改性法、等离子体改性法、表面涂覆改性法、电沉积改性法、自聚合改性法及改进基膜结构法等。本工作对阴离子交换膜改性及抗污染性能的研究进展进行了综述,对不同改性方法的优缺点进行了分析和评价。这些改性方法能提高阴膜表面的负电荷密度和亲水性、降低膜表面粗糙度和基膜含水率等,因此可以改善阴离子交换膜的抗污染性能。然而,目前研究获得的改性阴离子交换膜仍存在修饰层不稳定、抗污染性能不理想和性能测试不系统等缺点,需进一步优化改性方法、改性工艺、组分修饰及性能测试等,以获得抗污染性能稳定且效果良好的改性阴离子交换膜。     

多巴胺改性单价选择性阴离子交换膜制备及表征

以CuSO_4和H_2O_2为氧化剂,诱导多巴胺(DA)快速聚合,在商品膜表面形成荷负电的聚多巴胺(PDA)电解质层,制备具有1、2价阴离子选择分离功能的离子交换膜。通过扫描电子显微镜、红外光谱仪、Zeta电位分析仪等表征手段对PDA复合膜的表面结构和性质进行了分析,同时还考察了多巴胺含量对膜性能的影响。结果表明,当多巴胺的质量浓度为1 g/L时,PDA聚集物在膜表面均匀分布,PDA复合膜表现出良好的选择透过性(P(Cl-/SO_4~(2-))=5.49),对Cl~-与SO_4~(2-)有一定的分离效果;膜面电阻较低(R(Cl~-)=2.61Ω·cm~2、R(SO_4~(2-)))=6.13Ω·cm~2)和较高的离子交换容量(2.19 mmol/g),赋予PDA复合膜一定的实用价值。且在实际运行过程中具有良好的稳定性。     

高性能交联型SEBS基碱性阴离子交换膜的制备及性能

将苯乙烯-乙烯-丁烯-苯乙烯嵌段共聚物(SEBS)进行氯甲基化反应,加入苄基四甲基胍(BTMG)和二正丁胺(DBA)进行反应,制备了一类含胍阳离子交联的SEBS基SEBS-BTMG-DBA碱性阴离子交换膜(简称碱性膜)。为进一步提高SEBS-BTMG-DBA的OH-传导率,将其通过三甲胺(TMA)进行二次季铵化反应,成功制备了一类高导电率、高化学稳定性的SEBS基SEBS-TMA碱性膜。结果表明:80℃时,SEBS-TMA碱性膜的OH-传导率为51.50 mS/cm,离子交换容量为1.41 maq/g,明显高于未二次季铵化处理的SEBS-BTMG-DBA碱性膜;SEBS-TMA碱性膜的杨氏模量为356.5 MPa,在80℃条件下,1 mol/L的NaOH溶液中510 h后仍保持90%以上的OH-传导率。所制SEBS-TMA碱性膜在碱性燃料电池中有较好的应用前景。     

电渗析用季铵化聚氯乙烯均相阴离子交换膜的制备

以1-甲基咪唑(N-MI)为季铵化试剂一步法对聚氯乙烯(PVC)功能化改性，并制备了均相PVC阴离子交换膜，避免了传统阴离子交换膜制备过程中的氯甲基化步骤。通过对比研究，优化后的PVC-N-MI-5表现出较好的综合性能。离子交换容量和迁移数分别高达2.89 mmol·g^–1和98.4%；吸水率和溶胀率分别为4.24%和0.21%，低于商业JAM-5阴离子交换膜(4.87%和3.33%)；脱盐率、电流效率以及能耗分别为98.38%、55.8%和5.1 kW·h·(kg NaCl)^–1，可与商业JAM-5(93.0%、55.2%和4.6 kW·h·(kg NaCl)^–1)相比较。低廉的原料与简便的制备过程以及相对良好的电渗析应用性能，表明所制备的PVC-N-MI-5具有一定的应用前景。     

Preparation and characterization of ABS/HIPS heterogeneous anion exchange membrane filled with activated carbon

Acrylonitrile‐butadiene‐styrene (ABS)/high impact polystyrene (HIPS) blend heterogeneous anion exchange membranes were prepared by phase inversion method using tetrahydrofuran as solvent and anion exchange resin powder as functional group agent. Activated carbon was selected as inorganic filler additive. The additive concentration effect on properties of the prepared membranes was studied. Ultrasonic method was used to help appropriate dispersion of particles in the membrane's matrix. Scanning optical microscopy showed that sonication has a significant influence on distribution of resin particles in the membrane matrix and makes it possible to form more uniform phase. Moreover, images showed a relatively uniform surface for membranes. The increase of activated carbon concentration in casting solution led to a decline in membrane water content. The ion exchange capacity, membrane potential, permselectivity, transport number, ion permeability, ionic flux, and current efficiency of prepared membranes all were increased initially by the increase in additive concentration up to 1% wt and then they showed decrease trend with higher increase in additive concentration from 1 to 4% wt. Conversely, the electrical resistance and energy consumption showed opposite trends. In addition, with more additive loading, the oxidative stability of membranes was slightly decreased and their thermal stability was increased. Membrane with 1% wt additive loading exhibited higher efficiency and electrochemical properties in comparison with other prepared membranes in this research. Furthermore, prepared membranes exhibited suitable electrochemical properties compared to a commercial heterogeneous anion exchange membrane with the same experimental conditions. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

降冰片烯类季铵型阴离子交换膜的制备

通过环状烯烃双键打开, 首尾相接形成聚合物的方法, 设计合成了含有季铵阳离子作为功能化基的降冰片烯衍生物单体QRPhNB, 通过开环异位聚合(ROMP)制备得到阴离子交换膜材料, 流延成膜后的分析结果表明:当单体与降冰片二烯1:2投料时所得到的阴离子交换膜的IEC值为1.26 mequiv·g^-1, 其最高离子传导率为20.05 mS·cm^-1;吸水率为14.3%。     

Preparation of anion exchange membranes based on pyridine functionalized poly(vinyl alcohol) crosslinked by 1,4-dichlorobutane

A series of anion exchange membranes [pyridine functionalized-poly(vinyl alcohol)-1,4-dichlorobutane (PVA-PY-DL_x)] were synthesized by using PVA-PY as polymer matrix and DL as crosslinker and iodomethane as quaternization reagent. During the experiment, pyridine groups grafted on PVA were transformed into quaternary ammonium group during the formation process of the crosslinked structure and the quaternization routine by iodomethane. The characterization results revealed that the PVA-PY-DL_x membranes have been successfully prepared and the crystallinity increases with increase of DL. PVA-PY-DL_x membranes have smooth and uniform morphology. The introduction of crosslinked structure improves the mechanical properties and dimensional stability of the PVA-PY-DL_x membrane, enhances the alkali resistance. When the mass content of DL was 4.0%, composite membrane had the maximum tensile strength (44.2 MPa), and the OH⁻ conductivity reaches 1.05 × 10⁻² S cm⁻¹ at 70 °C. The accelerated aging experiment was carried out in 3 mol L⁻¹ potassium hydroxide (KOH) solution for 120 h at 80 °C, which revealed that the anionic conductivity of PVA-PY-DL_4.0 membrane retains 79.6% of its initial conductivity, showing better stability of alkali stability. Methanol permeability of PVA-PY-DL_x membranes was only the 0.37–0.72% of the Nafion-117 membrane in 3 mol L⁻¹ methanol at 60 °C. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47395.     

可控型季铵化降冰片烯衍生物阴离子交换膜的制备

为了提高阴离子交换膜的离子传导率,本文以降冰片烯二酸酐为原材料,单体中引入两个官能团提高单位体积内离子交换容量制备了阴离子交换膜。通过Materials Studio(MS)软件计算反应能垒,分析判断双季铵化单体形成与否的可行性。模拟计算与实验结果表明:分子结构设计合理,实验方法可行。当单体与降冰片烯比例为1:2.5时,最高离子传导率σ达到65.21 mS·cm^-1,离子交换容量为2.56 mequiv·g^-1,吸水率为22.6%。     

燃料电池用碱性膜材料的研究进展

碱性膜直接甲醇燃料电池因为结合了质子交换膜燃料电池和液体碱燃料电池的优点而产生自身独特的性质,使其可以在一定程度上弥补质子交换膜燃料电池以及液体碱燃料电池的缺点而尤其引人关注。其中碱性膜电解质为碱性膜燃料电池的核心组件,其性能直接关系到燃料电池的性能及寿命。截至目前,关于碱性膜材料的制备及应用方面的报道较多,涉及的碱性膜电解质的种类也较多。本文以燃料电池用碱性膜电解质为综述内容,对国内外关于碱性膜电解质的研究报道进行系统的梳理和介绍。     

Direct methanol alkaline fuel cells with catalysed anion exchange membrane electrodes

Membrane electrodes prepared by chemical deposition of platinum directly onto the anion exchange membrane electrolyte were tested in direct methanol alkaline fuel cells. Data on the cell voltage against current density performance and anode potentials are reported. The relatively low fuel cell performance was probably due to the low active surface area of Pt deposits on the membrane comparing to other membrane electrode assembly (MEA) fabrication methods. However, the catalysed membrane electrode showed good performance for oxygen reduction. A reduction in cell internal resistance was also obtained for the catalysed membrane electrode. By combining the catalysed membrane electrodes with a catalysed mesh, maximum current density of 98 mA cm^–2 and peak power density of 18 mW cm^–2 were achieved.