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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
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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
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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
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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
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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
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Nagendran A Vijayalakshmi A Arockiasamy DL Shobana KH Mohan D 《Journal of hazardous materials》2008,155(3):477-485
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
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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
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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
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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
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H. Susanto A. Roihatin N. Aryanti D.D. Anggoro M. Ulbricht 《Materials science & engineering. C, Materials for biological applications》2012,32(7):1759-1766
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
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Wanyue Ouyang Simin Zhang Xun Wang 《Small (Weinheim an der Bergstrasse, Germany)》2023,19(12):2206018
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
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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