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1.
以聚醚砜(PES)为膜材料,聚乙烯吡咯烷酮(PVP)为添加剂,N,N-二甲基乙酰胺为溶剂,采用相转化法制备了对PEG的截留分子量为20 000的聚醚砜超滤膜.通过对操作压力、料液的温度和浓度等条件的变化对蛋白质截留率、膜通量及乳糖透过率影响的分析,研究了不同的影响因素对乳糖超滤效果的影响规律.并确定了最佳工艺条件:压力在0.3 MPa左右较适宜,温度为50~60℃,料液浓度为100~150 g/L,处理时间为45~60 min.比较了不同清洗剂对PES膜超滤性能恢复的效果.结果显示,当超滤1 h通量减少一半时,用0.5%的NaOH清洗20 min后就可以恢复70%的膜通量.  相似文献   

2.
聚醚砜超滤膜的亲水化改性研究进展   总被引:6,自引:0,他引:6  
聚醚砜(PES)超滤膜的疏水性导致在处理水的过程中驱动力高、易污染,需要亲水化改性.调研了PES超滤膜的亲水化改性方法:物理共混、化学共聚、表面物理吸附、表面化学处理、表面接枝等.围绕亲水化综述了PES超滤膜亲水改性的研究进展.  相似文献   

3.
聚醚砜(PES)是一种综合性能优良的聚合物成膜材料,熔喷非织造布具有良好的过滤效能并广泛应用于空气的过滤.聚醚砜/非织造布复合膜是以PES膜材、致孔剂聚乙烯吡络烷酮(PVP)和溶剂N,N-二甲基乙酰胺(DMAc)作为铸膜液并涂覆在熔喷非织造布上,然后转移至凝固浴中成膜.通过控制铸膜液组分的不同比例、凝固浴温度和第一凝固...  相似文献   

4.
多元合金超滤膜研制   总被引:15,自引:6,他引:9  
主要研究了聚醚砜(PES),聚砜(PSF)和磺化聚砜(SPSF)共混所形所的多元合金超滤膜的性能和膜的孔径分布特性,初步探讨了多元合金超滤膜的成孔机理,并对共混体系的组成及相容性与合金超滤膜性能问题的关系作了详细讨论,研究结果且明,共混可明显改善超滤膜的孔径分布和膜的孔结构,为制备高性能越滤膜提供一种有效途径。  相似文献   

5.
对测定中空纤维超滤膜孔径大小及其分布的物质迁移方程法进行了改进,并考察了浓度对聚醚砜(PES)中空纤维膜孔径大小及其分布的影响.随纺丝液中PES质量浓度的增大,膜的孔径变小,对聚乙二醇的表观截留率增大,膜的纯水透过率减小,在大约24%的PES质量浓度时出现临界值,大于该临界值,膜的结构和性能均发生急剧变化.  相似文献   

6.
Scanning electrochemical microscopy (SECM), operated in reverse imaging mode (RIM), has been used to visualize the steady-state transport of molecules entering into porous membranes. RIM imaging is advantageous for investigating transport across biological membranes in situations where the SECM tip can access only the exterior membrane surface. Examples of RIM images of a synthetic membrane (mica with pores filled with the ion-selective polymer Nafion) and a biological membrane (hairless mouse skin) recorded during diffusive and iontophoretic transport, are reported. RIM imaging during diffusive transport allows visualization of the depletion of solute molecules in the solution adjacent to the pore openings. However, an accumulation of solute molecules above the pore opening is observed during iontophoresis, which is a consequence of the separation of the solute from the solvent (i.e., ultrafiltration). The separation results from differences in the rates of molecule transfer across the pore/solution interface when electroosmotic flow is operative. The results suggest that RIM imaging may be useful for measuring the kinetics of interfacial molecule transfer at biological membranes.  相似文献   

7.
聚氯乙烯/聚醚砜共混小孔超滤膜的研制   总被引:4,自引:0,他引:4  
聚氯乙烯与聚醚砜属部分相容体系。采用溶胶-凝胶相转化法,改变聚合物共混比例、混合溶剂、添加剂用量,制备了一系列聚氯乙烯/聚醚砜(PVC/PES)共混超滤膜。通过调配铸膜液中聚合物共混比例,可大大提高共混膜的强度和韧性。其水通量和截留率与同类日本产高分子分离膜相比,均有较大提高。  相似文献   

8.
竹子是一种以竹纤维为增强体、多孔木质素为基体而组成的天然复合材料.本文借鉴竹子的结构特征,采用高性能热塑性聚合物浸没沉淀相转化法在玻璃纤维(GF)表面沉积梯度孔径分布的多孔聚醚砜(PES)基体,制备仿竹结构单丝玻璃纤维增强多孔聚醚砜基复合材料(GF/PES),并对其微观形貌、拉伸力学性能和“温度-模量”智能响应性进行了...  相似文献   

9.
以间苯二胺(MPDA)和均苯三甲酰氯(TMC)为反应单体,通过界面聚合方法成功在聚醚砜大孔基膜上形成复合层制备出纳滤膜。研究了单体浓度、界面聚合时间对复合膜性能的影响。通过红外光谱测试(ATR-FT-IR)和扫描电子显微镜(SEM)对复合纳滤膜结构与形貌进行表征,证实了功能层的存在。制得的纳滤膜在压力2 MPa下复合层...  相似文献   

10.
通过亲电取代反应成功合成了磺化聚醚砜并制备了聚醚砜/磺化聚醚砜共混膜。膜的水吸附量和水接触角实验表明,和单纯的聚醚砜膜相比,由于磺酸基的存在使得共混膜的亲水性得到提高。牛血清蛋白吸附实验结果显示:与聚醚砜膜相比,共混膜能有效地抑制牛血清蛋白的吸附。凝血时间实验则表明,聚醚砜/磺化聚醚砜共混膜的凝血时间比纯聚醚砜膜的凝血时间延长了2~3倍,因而共混膜的血液相容性较纯聚醚砜膜得到提高。  相似文献   

11.
Toxic heavy metal ion removal from industrial effluents are gaining increased visibility owing to environmental concern and saving precious materials. In this work, an attempt has been made to remove the valuable metal ions using modified ultrafiltration (UF) blend membranes based on cellulose acetate (CA) and sulfonated poly(ether imide) (SPEI) were prepared in the presence and absence of additive, poly(ethylene glycol) 600 (PEG600) in various compositions. Prepared membranes were characterized in terms of pure water flux (PWF), water content and membrane hydraulic resistance. High flux UF membranes were obtained in the range of 15-25 wt% SPEI and 2.5-10 wt% PEG600 in the polymer blend. The molecular weight cut-off (MWCO) of the blend membranes were determined using protein separation studies found to vary from 20 to greater than 69 kDa. Surface morphology of the blend membranes were analysed with scanning electron microscopy. Studies were carried out to find the rejection and permeate flux of metal ions such as Cu(II), Ni(II), Zn(II) and Cd(II) using polyethyleneimine as the chelating ligand. On increasing the composition of SPEI and PEG600, the rejection of metal ions is decreasing while the permeate flux has an increasing trend. These effects are due to the increased pore formation in the CA/SPEI blend membranes because of the hydrophilic SPEI and polymeric additive PEG600. In general, it was found that CA/SPEI blend membranes displayed higher permeate flux and lower rejection compared to pure CA membranes. The extent of separation of metal ions depends on the affinity of metal ions to polyethyleneimine to form macromolecular complexes and the stability of the formed complexes.  相似文献   

12.
以PEI超滤膜为支撑层,PEG为复合层,制备了PEG/PEI渗透汽化RCC汽油脱硫复合膜.通过傅立叶红外光谱仪对PEG/PEI复合膜表面进行了结构分析,考察了交联前后官能团的变化.通过扫描电子显微镜分析了复合膜表面和断面的形态.将制备的复合膜应用于正庚烷和噻吩体系,首先考察了膜的溶胀性和稳定性.研究了不同聚合物PEG浓度、交联剂浓度,交联温度和交联时间对分离性能的影响,从而得到最佳制膜条件.  相似文献   

13.
采用凝胶相转化法,以聚醚砜(PES)、杂萘联苯聚芳醚砜酮(PPESK)为膜材料,N,N-二甲基乙酰胺(DMAc)、N-甲基吡咯烷酮(NMP)为溶剂,通过改变铸膜液中非溶剂添加剂甲酰胺的含量,在平板刮膜机上制备了一系列超滤膜。考察了甲酰胺对铸膜液黏度、膜结构和性能的影响,对PES/DMAc和PPESK/NMP铸膜液体系中甲酰胺的作用规律进行了研究。  相似文献   

14.
纳滤膜孔结构、荷电性质、分离机理及动电性质研究进展   总被引:1,自引:0,他引:1  
纳滤膜拥有介于反渗透膜和超滤膜之间的截留分子量,同时对无机盐的截留率随着盐的种类和浓度而改变,广泛应用于各种水净化处理和产品精制分离过程.文章从纳滤膜孔结构和荷电性质、纳滤膜分离机理及其模型、纳滤膜动电性质等三个方面对纳滤膜分离技术20多年来的基础及应用研究进展进行回顾和总结,简要分析了今后纳滤膜分离技术的发展方向及趋势.  相似文献   

15.
以相转化法制备了磺化聚砜(SPSF)/聚醚砜(PES)共混新型纳滤膜,并研究了磺化聚砜的磺化度以及聚醚砜/磺化聚砜的共混质量比对低分子量PEG的截留率和脱盐率性能的影响.结果表明:在操作压力为0.5MPa,料液温度为25℃下,当PES/磺化度10%SPSF共混比为6∶4时,SPSF/PES共混膜对PEG1000、PEG800和PEG600的截留率分别为99.8%、81.0%和57.8%,对硫酸钠、氯化钠的截留率分别为69.0%和23.5%,SPSF/PES共混膜的纯水通量为90.3L/(m2.h).  相似文献   

16.
DMAc / LiCl 体系下纤维素 / 聚醚砜共混膜的制备与表征   总被引:1,自引:1,他引:0  
采用 N,N-二甲基乙酰胺(DMAc) / 氯化锂(LiCl)体系作为纤维素溶剂,制备了纤维素 / 聚醚砜共混膜。探讨了共混比对膜的断裂强度、断裂伸长率和纯水通量等膜性能的影响,并确定了纤维素 / 聚醚砜最佳共混比为 1 : 16。 对共混膜进行了 SEM 和 DSC 分析,确认了纤维素 / 聚醚砜共混膜是一个相容的聚合物共混体系。  相似文献   

17.
This paper compares the performance of different hydrophilization methods to prepare low fouling ultrafiltration (UF) membranes. The methods include post-modification with hydrophilic polymer and blending of hydrophilic agent during either conventional or reactive phase separation (PS). The post-modification was done by photograft copolymerization of water-soluble monomer, poly(ethylene glycol) methacrylate (PEGMA), onto a commercial polyethersulfone (PES) UF membrane. Hydrophilization via blend polymer membrane with hydrophilic additive was performed using non-solvent induced phase separation (NIPS). In reactive PS method, the cast membrane was UV-irradiated before coagulation. The resulting membrane characteristic, the performance and hydrophilization stability were systematically compared. The investigated membrane characteristics include surface hydrophilicity (by contact angle /CA/), surface chemistry (by FTIR spectroscopy), and surface morphology (by scanning electron microscopy). The membrane performance was examined by investigation of adsorptive fouling and ultrafiltration using solution of protein or polysaccharide or humic acid. The results suggest that all methods could increase the hydrophilicity of the membrane yielding less fouling. Post-modification decreased CA from 44.8 ± 4.2o to 37.8 ± 4.2o to 42.5 ± 4.3o depending on the degree of grafting (DG). The hydrophilization via polymer blend decreased CA from from 65o to 54o for PEG concentration of 5%. Nevertheless, decreasing hydraulic permeability was observed after post-modification as well as during polymer blend modification. Stability examination showed that there was leaching out of modifier agent from the membrane matrix prepared via conventional PS after 10 days soaking in both water and NaOH. Reactive PS could increase the stability of the modifier agent in membrane matrix.  相似文献   

18.
Block copolymers (BCPs) have enduring appeal for its intriguing assembly behaviors. Nevertheless, the unsatisfactory mechanical properties of BCPs make it a problem to fabricate freestanding membranes and hindered practical applications. Herein, a freestanding membrane with tunable pore size is prepared simply by co-assembly of BCPs and subnanometer nanowires (SNWs), combining the abundant function of BCPs and prominent mechanical properties of SNWs. Benefited from synergy of the components and the hierarchical structure, the tensile strength of composite membrane is promoted by two orders of magnitude compared to that of BCPs. With the columnar pores aligning vertically to surfaces and the pore size regulated by processing conditions, the membranes exhibit precise size-selected effect in ultrafiltration of Au nanoparticles (Au NPs) and can distinct NPs with diameter difference as tiny as 5 nm, demonstrating the promising prospect in separation technology and even widespread fields.  相似文献   

19.
刘俊  陈远萌 《材料保护》2005,38(11):37-39
为了探讨固化工艺及配方对环氧树脂体系微观结构的影响,研究了用4,4′-二氨基二苯砜(DDS)作固化剂的环氧树脂与聚醚砜(PES)共混体系.采用差示扫描量热法(DSC)和扫描电镜(SEM)研究其相分离和微观结构,并通过改变聚醚砜的用量和固化工艺条件对其进行控制.结果表明,在环氧树脂与聚醚砜间形成了半互穿网络,对应于环氧态和聚醚砜态的玻璃化转变温度彼此靠近.通过控制反应进程和聚醚砜用量,可以获得不同的相结构,加入较多的聚醚砜或采用较高的固化温度,有利于提高聚醚砜增韧环氧树脂的冲击性能.  相似文献   

20.
选择乙烯的摩尔分数为38%的乙烯-乙烯醇的共聚物(EVOH)为原料,聚乙二醇(PEG)为稀释剂,采用热致相分离方法(TIPS)制备了亲水性高分子微孔膜.用扫描电子显微镜观测了微孔膜的形态.结果表明,分相的方式及微孔的大小由聚合物的含量及冷却速度决定.EVOH含量越少,则越易发生液-液相分离;冷却速度越慢,则微孔的尺寸也越大、EVOH摩尔分数为60%时,如果冷却速度很慢,则发生液-固相分离;如果冷却速度较快,则可同时观察到液-固相分离和液-液相分离的形态.  相似文献   

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