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1.
以浓硫酸为溶剂 ,氯磺酸为磺化剂对聚醚砜 (PES)进行了磺化 ,制备了不同磺化度的磺化聚醚砜 (SPES)。探讨了反应的影响因素 ,分析了 SPES的热稳定性。结果表明 SPES的 Tg较 PES升高 ,随着磺化度的增加 ,SPES的降解温度降低。  相似文献   

2.
《应用化工》2022,(8):1641-1644
制备了磺化聚醚砜SPES膜和3种磺化度的SPES/PES共混膜用于催化酯化酸化油制备生物柴油。考察了磺化度、催化膜用量、酸化油和甲醇质量比、反应时间对酯化反应的影响。结果表明,单独使用SPES催化膜较脆,而SPES/PES共混膜机械强度较好,其中磺化度20.3%SPES/PES膜的重复使用性能最好。SPES/PES共混膜催化酯化酸化油制备生物柴油的最佳反应条件为:磺化度20.3%的SPES/PES共混膜为催化剂,催化膜用量1.66%,醇油质量比为1∶1,反应温度65℃,反应时间6 h,此时酸化油转化率为97.44%。  相似文献   

3.
制备了磺化聚醚砜SPES膜和3种磺化度的SPES/PES共混膜用于催化酯化酸化油制备生物柴油。考察了磺化度、催化膜用量、酸化油和甲醇质量比、反应时间对酯化反应的影响。结果表明,单独使用SPES催化膜较脆,而SPES/PES共混膜机械强度较好,其中磺化度20.3%SPES/PES膜的重复使用性能最好。SPES/PES共混膜催化酯化酸化油制备生物柴油的最佳反应条件为:磺化度20.3%的SPES/PES共混膜为催化剂,催化膜用量1.66%,醇油质量比为1∶1,反应温度65℃,反应时间6 h,此时酸化油转化率为97.44%。  相似文献   

4.
以浓硫酸为聚醚砜(PES)的溶剂和磺化剂,制备磺化聚醚砜(SPES)。选取磺化度(DS)为14%的SPES溶液,制备PES-SPES共混膜,考察了共混膜的脱盐效果和抗污染性能。结果表明,共混膜的基质材料中,随SPES、PES的质量比的增加,共混膜表面膜孔径增大,断面结构由指状孔向海绵状孔转化,共混膜水通量增加,截留率降低,当SPES的DS为14%、SPES、PES的质量比0.75时,制得共混膜水通量为253.7 L/(m~2·h),对PEG6000、PEG10000和PEG20000的截留率分别为56.8%、74.5%和90.6%;共混膜在相同测试条件下对Na_2SO_4截留效果大于NaCl,经亲水改性的PES-SPES共混膜亲水性提高,抗污染性能明显增强。  相似文献   

5.
磺化聚醚砜微球制备及对亚甲蓝的吸附   总被引:1,自引:0,他引:1  
采用气体三氧化硫法制备了磺化聚醚砜(SPES),并对其进行了表征。将制得的SPES用于制备吸附微球,研究了压缩空气流量对所成微球大小的影响,分析了微球内部的孔结构。对比SPES和聚醚砜(PES)2种微球对水中亚甲蓝(MB)的吸附,发现SPES微球对MB的吸附性能明显优于PES微球对MB的吸附性能。  相似文献   

6.
为了改善聚醚砜(PES)膜的抗污染性能,将PES磺化,通过磺酸基与Ag+的相互作用及维生素C的还原作用,将Ag负载在磺化聚醚砜(SPES)膜表面,制备了负载纳米银磺化超滤聚醚砜膜(SPES@Ag)。通过扫描电镜(SEM)、原子力显微镜(AFM)、X射线衍射(XRD)对SPES@Ag超滤膜进行了表征,并通过细胞吸附法进行了抗菌性测试。结果表明,纳米银的平均尺寸为120 nm,它的负载提高了超滤膜的抗菌性能,对大肠杆菌、假单胞菌和金黄色葡萄球菌的抗菌率分别达到了96.7%,98.3%,87.7%。此外,通量和截留率的测试的结果表明,SPES@Ag超滤膜的水通量为438.4 L/m2.h,对牛血清蛋白(BSA)的截留率达到94.5%。  相似文献   

7.
磺化聚醚砜(SPES)/聚醚砜(PES)合金超滤膜的研究   总被引:7,自引:0,他引:7  
本文研究了磺化聚醚砜 (SPES) /聚醚砜 (PES)合金组份变化对膜性能的影响 ,通过选择适当的合金比例研制得到超滤膜 ,在 0 .2Mpa操作压力下 ,对聚乙二醇分子量为 1万的截留率大于 90 % ,水通量为 80L/m2 ·h ,对阴离子脱盐率PO3 -4 >SO2 -4 >CL-。通过扫描电镜观察膜的断面结构 ,结果表明 :PES膜断面形态属于典型的非对称指状孔结构 ,SPES/PES膜断面形态是致密的海绵状结构 ,致密层部分比SPES薄 ,SPES膜断面形态是较厚的海绵状结构 ,致密层部分多  相似文献   

8.
采用电镜和孔径分布测定仪对自制聚醚砜( PES)和磺化聚醚砜(SPES)膜进行表征,根据Darcy-Poiseuille定律研究PES膜和SPES膜过滤牛血清蛋白液(BSA)阻力分布情况.结果表明,PES膜孔径为0.22~0.27 μm,初始纯水通量为642 L·m-2·h-1,过滤质量浓度为1 g·L-1的BSA溶液时平衡通量为30.4~31.9 L·m-2· h-1; SPES膜孔径为5.2~11.1 nm,初始纯水通量为8.1 L·m-2·h-1,质量浓度为1 g·L-1的BSA时平衡通量为3.4~6.9 L· m-2·h-1.过滤时PES膜阻力主要集中在吸附和堵孔阻力,2者相加为总阻力的91.1%;而SPES膜阻力主要集中在膜本身的阻力,为总阻力的41.8%,其次为堵孔阻力,占总阻力的38.3%.经清洗后,PES膜的纯水通量可以恢复到82%,而SPES膜可以恢复到494%.  相似文献   

9.
以聚醚砜(PES)为基体,磺化聚醚砜(SPES)为催化活性成分,通过溶剂挥发法制备SPES/PES共混膜,用于酸化油(酸值153 mg KOH/g)酯化反应制备生物柴油,并研究了SPES/PES共混型催化膜酯化反应动力学。结果表明,在不同反应温度(45,55,65,75℃),不同的催化剂用量(0.68%,1.35%和2.70%)以及醇油质量比(1∶1,2∶1,5∶1,8∶1和10∶1)条件下,通过反应动力学计算出相应的反应速率以及反应级数。随着催化剂用量和醇油质量比的增加,反应速率逐渐增加,反应级数也增大,平均反应级数为n=2.2,而指前因子和活化能逐渐减小,说明由反应控制逐渐转为混合控制和反应控制。建立了SPES/PES共混型催化膜酯化反应动力学模型。得到实验值与理论值吻合程度较高(误差在±5%左右),验证了动力学模型的正确性。  相似文献   

10.
以聚醚砜(PES)为基体,磺化聚醚砜(SPES)为催化活性成分,通过溶剂挥发法制备SPES/PES共混膜,用于酸化油(酸值153 mg KOH/g)酯化反应制备生物柴油,并研究了SPES/PES共混型催化膜酯化反应动力学。结果表明,在不同反应温度(45,55,65,75℃),不同的催化剂用量(0.68%,1.35%和2.70%)以及醇油质量比(1∶1,2∶1,5∶1,8∶1和10∶1)条件下,通过反应动力学计算出相应的反应速率以及反应级数。随着催化剂用量和醇油质量比的增加,反应速率逐渐增加,反应级数也增大,平均反应级数为n=2.2,而指前因子和活化能逐渐减小,说明由反应控制逐渐转为混合控制和反应控制。建立了SPES/PES共混型催化膜酯化反应动力学模型。得到实验值与理论值吻合程度较高(误差在±5%左右),验证了动力学模型的正确性。  相似文献   

11.
通过将PES掺入高磺化度的SPEEK进行共混改性,采用流延法制备了一系列不同PES含量的SPEEK/PES共混膜,获得了SPEEK/PES共混膜的离子交换容、含水率、质子电导率等参数,特别测定了在全钒液流电池工作条件下钒(IV)离子渗透率。综合考察发现,当磺化温度为45℃,磺化时间控制为4h,得到SPEEK的DS为55%,掺入10%的PES,此时共混膜的电导率为0.08S/cm,钒(IV)离子渗透率为0.38×10^-6cm2/min,对钒(IV)离子选择性为Nation膜的5倍,含水率为35%,共混膜综合性能最好,基本满足全钒液流电池(VRB)的使用需求。  相似文献   

12.
通过改变共聚单体种类,探究主链元素种类对聚合物质子交换膜性能的影响。以3,3'-二磺酸基钠盐-4,4'-二氟二苯砜为磺化单体,4,4'-二氟二苯砜为非磺化单体,4,4'-二羟基二苯醚或4,4'-二巯基二苯硫醚为共聚单体,通过亲核缩聚反应成功可控制备出磺化度分别为30%和50%的磺化聚芳醚砜(SPES)与磺化聚芳硫醚砜(SPTES)。采用流延法制备了两种聚合物的透明坚韧的质子交换膜。研究发现两种聚合物膜均显示出了良好的力学性能以及较为适中的吸水率与溶胀度。两种聚合物质子交换膜的起始分解温度达到250℃,具有良好的热稳定性。随磺化度的升高,两种聚合物膜的吸水率、溶胀率以及质子传导率均升高。由于主链硫较氧原子与苯环的共轭作用更强以及供电子硫原子与吸电子基团的相互作用,SPTES膜较SPES膜表现出更高的玻璃化转变温度(T g)、更低的溶胀率以及更高质子传导率。其中SPES-50与SPTES-50在80℃、100%RH条件下,质子传导率分别为0.136S/cm与0.142S/cm,表明其作为质子交换膜具有潜在的应用前景。  相似文献   

13.
A novel sulfonated poly(ether sulfone) (SPES)/phosphotungstic acid (PWA)/silica composite membranes for direct methanol fuel cells (DMFCs) application were prepared. The structure and performance of the obtained membranes were characterized by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), water uptake, proton conductivity, and methanol permeability. Compared to a pure SPES membrane, PWA and SiO2 doped membranes had a higher thermal stability and glass transition temperature (Tg) as revealed by TGA‐FTIR and DSC. The morphology of the composite membranes indicated that SiO2 and PWA were uniformly distributed throughout the SPES matrix. Proper PWA and silica loadings in the composite membranes showed high proton conductivity and sufficient methanol permeability. The selectivity (the ratio of proton conductivity to methanol permeability) of the SPES‐P‐S 15% composite membrane was almost five times than that of Nafion 112 membrane. This excellent selectivity of SPES/PWA/silica composite membranes indicate a potential feasibility as a promising electrolyte for DMFC. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

14.
Polyethersulfone (PES) was sulfonated by chlorosulfonic acid and concentrated sulfuric acid. The pure sulfonated PES (SPES) and modified SPES membranes were prepared by blending with different charged surface modifying macromolecules (cSMMs) namely, SPES/DEG‐HBS, SPES/PEG‐HBS, and SPES/PPG‐HBS. Membranes were characterized for their morphology, physical properties, and electrochemical properties in order to evaluate these membranes as cation exchange membranes. The blended membranes showed an increase in hydrophilicity, water uptake, and proton conductivity compared to the pure SPES membranes. The highest values of water uptake and proton conductivity were obtained for the SPES/PPG‐HBS blended membrane. Morphological studies revealed that the nodule size and surface roughness also influenced the water uptake, apart from the additional –SO3H group. Among the modified membranes, the SPES/DEG‐HBS blended membrane exhibited a lower methanol permeability value of 8.895 × 10−8 cm2 s−1 than the corresponding SPES membrane. The other two cSMM blended membranes showed higher methanol permeability values than SPES but still a smaller value than Nafion 117. The highest selectivity ratio (i.e., ratio of proton conductivity to methanol permeability) was obtained with the SPES/DEG‐HBS cSMM blended membrane. These results showed that the SPES/cSMM blended membranes have promise for possible use as a cation exchange membrane in fuel cells and electrolyzer applications.  相似文献   

15.
A cation‐exchange membrane based on a styrene/hydroxyethyl acrylate/lauryl methacrylate (Sty/HEA/LMA) terpolymer was prepared via a postsulfonation reaction for various sulfonation times. Sulfonic groups were introduced into the membrane structure with sulfuric acid as the sulfonating agent and silver sulfate as an initiator in a nitrogen atmosphere. Sulfonated Sty/HEA/LMA terpolymer membranes were characterized by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance as well as by determining the degree of sulfonation (DS), ion‐exchange capacity (IEC), water uptake (WU), and electrical property of the membranes. The presence of sulfonic groups in the sulfonated Sty/HEA/LMA terpolymer was confirmed by FTIR, and the resulting membrane showed an IEC of 1.29 meq/g and an electrical resistance of 0.1 Ω cm2. The WU of the prepared membranes increased with the DS at the reaction time. The surface morphology obtained by atomic force microscopy clearly showed an increase of roughness with reaction time. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

16.
Composite membranes of sulfonated poly(ethersulfone)/1,1-carbonyl diimidazole/1-(3-aminopropyl)-silane/silica (SPES/CDI/AS/SiO2) with silica of various contents (3, 5 and 8 wt%) were prepared as electrolytes for direct methanol fuel cells (DMFCs). Comparison was made with pure SPES and SPES/SiO2. The properties of the composite membranes were studied by FTIR, TGA, XRD, water and methanol uptake, proton conductivity. SPES/CDI/AS/SiO2 membranes were also characterized by scanning electron microscopy (SEM), which showed good adhesion between the modified sulfonic acid (-SO3H) groups of SPES and silica because of cross-linking with covalent bond formation and reduced cavities in the composites. This effect played an important role in reducing water uptake, methanol uptake and methanol permeability of the SPES/CDI/AS/SiO2 composites. The water and methanol uptake and also methanol permeability of the SPES/CDI/AS/SiO2 composite membrane with 8% SiO2 were found in the order 3.58%, 2.48% and 1.91×10?7 (cm2s?1), lower than those of SPES and Nafion 117. In SPES membrane of 16.94% level of sulfonation, the proton conductivity was 0.0135 s/cm at 25 °C, which approached that of Nafion 117 under the same conditions. Also, the proton conductivity of the SPES/CDI/AS/SiO2 8% membrane was 0.0186 s/cm, which was higher than that of SPES at room temperature. The preparation of SPES/SiO2 composites in the presence of AS and CDI, led to 63%, 56% and 64% reduction of water uptake, methanol uptake and methanol permeability, respectively without a sharp drop in proton conductivity of the composite membranes which featured a good balance between high proton conductivity, water and methanol uptake of SPES/CDI/AS/SiO2 membranes.  相似文献   

17.
Ion exchange membranes (IEMs) composed of sulfonated poly (ether sulfone) (SPES) and N-phthaloyl chitosan (NPHCs) were synthesized. NPHCs was employed in membrane fabrication to improve the porosity and hydrophilicity of membranes. The effect of blend ratio of sulfonation (DS) and NPHCs content on physico-chemical characteristics of home-made membranes was investigated. The morphology of prepared membranes was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffractometer (XRD) and scanning electron microscopy (SEM). SEM images revealed the formation of a more porous membrane structure and smoother surface. The electrochemical and physical properties of CEMs were characterized comprising water content, contact angle, ion exchange capacity (IEC) and thermal stability. Membrane water content, surface hydrophilicity and IEC were enhanced with increase of DS and NPHCs blend ratios in casting solution. Furthermore, the diffusion coefficient was also improved slightly with increase of DS and NPHCs blend ratios in prepared membranes. Membrane potential, permselectivity, transport number and areal membrane resistance all showed decreasing trends by the increase in NPHCs blend ratio in casting solution. These results indicated that the prepared membrane has good prospective and great potential for desalination in electrodialysis applications.  相似文献   

18.
A series of sulfonated poly(ether sulfone) (SPES)/silica composite membranes were prepared by sol–gel method using tetraethylorthosilicate (TEOS) hydrolysis. Physico–chemical properties of the composite membranes were characterized by thermogravimetric analysis (TGA), X‐ray diffraction (XRD), scanning electron microscope–energy dispersive X‐ray (SEM–EDX), and water uptake. Compared to a pure SPES membrane, SiO2 doping in the membranes led to a higher thermal stability and water uptake. SEM–EDX indicated that SiO2 particles were uniformly embedded throughout the SPES matrix. Proper silica loadings (below 5 wt %) in the composite membranes helped to inhibit methanol permeation. The permeability coefficient of the composite membrane with 5 wt % SiO2 was 1.06 × 10?7 cm2/s, which was lower than that of the SPES and just one tenth of that of Nafion® 112. Although proton conductivity of the composite membranes decreased with increasing silica content, the selectivity (the ratio of proton conductivity and methanol permeability) of the composite membrane with 5 wt % silica loading was higher than that of the SPES and Nafion® 112 membrane. This excellent selectivity of SPES/SiO2 composite membranes could indicate a potential feasibility as a promising electrolyte for direct methanol fuel cell. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010  相似文献   

19.
Novel composite sulfonated poly(ether sulfone)(SPES)/phosphotungstic acid (PWA)/attapulgite (AT) membranes were investigated for direct methanol fuel cells (DMFCs). Physical–chemical properties of the composite membranes were characterized by FTIR, DSC, TGA, SEM‐EDX, water uptake, tensile test, proton conductivity, and methanol permeability. Compared with a pure SPES membrane, PWA, and AT doping in the membrane led to a higher thermal stability and glass transition temperature (Tg) as revealed by TGA and DSC. Tensile test indicated that lower AT content (3%) in the composite can significantly increase the tensile strength, while higher AT loading demonstrated a smaller contribution on strength. Proper PWA and AT loadings in the composite membranes can increase the proton conductivity and lower the methanol cross‐over. The proton conductivity of the SPES‐P‐A 10% composite membrane reached 60% of the Nafion 112 membrane conductivity at room temperature while the methanol permeability was only one‐fourth of that of Nafion 112 membrane. This excellent performances of SPES/PWA/AT composite membranes could indicate a potential feasibility as a promising electrolyte for DMFC. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   

20.
孙媛媛  屈树国  李建隆 《化工进展》2016,35(9):2850-2860
Nafion膜具有优良的化学稳定性和导电性能,但是它成本高,高温下几乎不导电。本文回顾了Nafion替代膜之一——磺化聚醚醚酮(SPEEK)膜及SPEEK/离子液体(IL)复合膜的研究进展。介绍了SPEEK制备的两种方法:直接磺化法和磺化单体聚合法,其中直接磺化法工艺简单,但磺化度(DS)≤1.0,反应较难控制;磺化单体聚合法DS可控,但工艺复杂,原料有毒。简述了温度、反应时间、原料配比、磺化单体种类、制膜工艺及溶剂对SPEEK膜性能的影响:直接磺化法中DS与温度成负相关,与反应时间成正相关,与原料配比关系不大;磺化单体聚合法中DS受磺化单体的种类和氟酮与磺化氟酮的比例影响较大。着重介绍了SPEEK/咪唑离子液体复合膜和SPEEK/季铵盐离子液体复合膜的研究现状及应用于质子交换膜燃料电池(PEMFC)时存在的问题。最后对SPEEK/IL复合膜未来的研究方向进行了展望,即解决燃料电池运行过程中复合膜中离子液体流失及与Pt基催化剂相容性等关键问题,以提高PEMFC的性能。  相似文献   

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