电场强化制备荷电聚砜超滤膜及其性能

采用高压电场强化技术,结合相转化法制备荷电超滤膜。添加剂、溶剂与膜材料分别为聚乙烯吡咯烷酮(PVP K30)、N–甲基–2–吡咯烷酮(NMP)与聚砜(PSF),主要对膜分离性能受到高分子聚合物质量分数、凝固浴温度、电场强度等因素的影响进行了研究与分析。结果表明,高压电场强化不会改变膜的微观结构,但会影响膜的分离性能。实验得到最佳制膜条件:PSF质量分数为20%,PVP K30含量为6%,凝固浴温度为30℃,高压电场强化时间为40 s,电场强度为3 kV,此时,膜的分离性能达到最佳,膜的水通量为166 L/(m²·h),截留率为93.3%。     

PSF/PES共混膜的制备与优化

实验以聚砜(PSF)、聚醚砜(PES)为膜材料,N-甲基吡咯烷酮(NMP)为溶剂,水为凝胶剂,采用L-S相转化法制备了复合膜用共混基膜.按照均匀设计方法优化制膜条件,用SPSS软件处理实验结果得到模型方程,方程反映了各种因素及其交互作用对膜透水性能的影响规律,模型计算值与实验值吻合良好.对于给定的PES含量,随着共混物中PSF /PES 总量的增大,优化计算得到的PVP含量和丙酮含量增大,但相应的膜水通量减小.在上述理论指导下,实验制备基膜的纯水通量为290.6 L·m-2·h-1,对牛白蛋白的截留率达到88.2%.     

三醋酸纤维素正渗透膜的制备与性能初步研究

以高分子物质三醋酸纤维素(CTA)作为膜材料主要成分,将其溶解于1,4-二氧六环溶剂中,加入致孔剂聚乙烯吡咯烷酮K30(PVP),加热搅拌形成均匀铸膜液采用相转化法制备正渗透膜。在温度为(20±1)℃,原溶液为去离子水,汲取液为2 mol/L氯化钠溶液的条件下测试膜的性能,研究了CTA和PVP含量及预蒸发时间3种因素对正渗透膜性能的影响。结果表明,在1,4-二氧六环和乳酸体积分别为170和13.2 mL下,当CTA和PVP的质量分别为23、4 g,预蒸发时间为60 s时,正渗透膜的性能最佳,水通量可达10.24 L/(m2·h),溶质反混通量为6.68 g/(m2·h)。     

聚砜管式超滤膜的制备及其结构性能研究

采用浸没相沉淀法制备聚砜(PSF)管式超滤膜。以纯水通量、卵清蛋白截留率、扫描电镜表征膜的结构和性能,考察了PSF含量、凝固浴温度和组成、添加剂种类和含量对PSF管式膜成膜性能及结构的影响。结果表明,凝固浴温度升高、聚乙烯吡咯烷酮(PVP)含量增加、PEG-400含量增加,都可以使膜的水通量增加、截留率降低;而凝固浴中添加溶剂二甲基乙酰胺(DMAc)、铸膜液中PSF含量的增加,都可以使膜的通量减小,截留率升高。     

聚砜纳滤膜的制备

研究聚砜纳滤平板膜的制备,通过浸没相转化过程制备膜,讨论和研究聚砜(PSF)含量,聚乙烯吡咯烷酮含量,凝固浴温度和空气浴时间对膜结构、硫酸镁溶液水通量和截留率的影响,结果表明;聚砜(PSF)含量增加,凝固浴温度升高、空气浴时间增长时,都可以使膜水通量降低,截留增大,而聚乙烯吡咯烷酮(PVP)含量增加时水通量增加,截留率降低。     

亲水性聚偏氟乙烯超滤膜的制备

采用干-湿相转化法研究了聚偏氟乙烯(PVDF)中空纤维超滤膜的制备。选用PVDF为膜材料,N,N-二甲基乙酰胺(DMAc)为溶剂,聚乙烯吡咯烷酮(PVP)和聚乙二醇(PEG)为添加剂,考察了一定条件下PVDF和PVP的百分含量及PEG的分子量对膜孔径、机械性能、水通量及形貌结构的影响,用正交实验设计确定了制膜的最佳配方为:PVP含量14%,PVDF含量18%,PEG分子量为200。此配方下所制备的中空纤维膜圆整度较好,断裂强力为3.2 N,断裂伸长率为70%,泡点为0.43 MPa,平均孔径为0.081μm,纯水通量为178 L/(m~2·h)。     

高性能工业用聚砜平板复合膜的制备

考察了浸没沉淀相转化法制备高性能工业用聚砜(PSF)平板复合膜的影响因素,确定N-甲基吡咯烷酮(NMP)/水为溶剂/非溶剂体系,铸膜液中聚砜的质量分数为12%~16%,基膜1作为复合膜的支撑层基膜,利用聚乙烯吡咯烷酮K30(PVPK30)和氯化锂(Li Cl)组成的复合添加剂及PSF/PVP/Li Cl/NMP质量比为15/5/3/77组成的铸膜液制备的聚砜平板复合膜,用于石化废水处理,COD和浊度去除率分别为79.5%和96.8%,水通量为167.2 L/m2·h,废水处理效果明显,膜通量衰减慢,抗污染能力强。     

亲水性PEO/PSF复合膜的制备与性能研究

以聚砜(PSF)作为膜材料,再以聚乙烯吡咯烷酮(PVP)为致孔剂,聚氧化乙烯(PEO)为添加剂,N,N-二甲基乙酰胺(DMAc)为溶剂,通过浸没沉淀相转化法制备了一系列的PEO共混改性的PSF复合超滤膜。通过杯式超滤器,接触角测量仪,扫描电镜(SEM),红外光谱仪(FTIR)等表征手段探究了PEO的加入对复合膜性能的影响。结果表明,PEO的加入显著改善了膜的亲水性能和超滤性能。在PEO质量分数为0.8%时,改性的PEO/PSF复合膜性能最佳,纯水通量达到161.12 L/(m^2·h),对BSA溶液的截留率为99.05%。     

聚偏氟乙烯/纳米纤维素复合超滤膜的研究

以聚偏氟乙烯为原材料,聚乙烯吡咯烷酮( PVP K30)为添加剂,并向聚偏氟乙烯铸膜液中混入纳米纤维素,采用相转化工艺制备了复合超滤膜.通过正交试验分析了各因素对产品性能的影响,并得出了制备复合超滤膜的最优条件:聚偏氟乙烯质量分数为14％,添加剂PVP K30质量分数为0.5％,纳米纤维素加入量为0.7％,空气中溶剂蒸发时间为10s,凝胶浴为水.测定复合超滤膜的水通量、截留率、平均孔径、孔隙率、力学强度等一系列性能,膜的水通量为40.7 L/(m2·h),对牛血清蛋白的截留率为91.8％,孔隙率为52.3％,平均孔径为15.3 nm.     

添加剂对PSF/ER合金膜结构和性能的影响

介绍了大分子添加荆聚乙烯吡咯烷酮(PVP)和小分子添加荆H2O时聚砜(PSF)／环氧树脂(ER)合金膜结构和渗透、分离及成膜性能的影响。结果表明，添加荆使PSF／ER合金膜的水通量上升，截留率下降；PVP改善了PSF／ER合金膜的成膜性能，当水质量分数大于0．8％时，PSF／ER合金膜的成膜性能下降。     

Studies on cellulose acetate–carboxylated polysulfone blend ultrafiltration membranes—Part II

Hydrophilic polysulfone ultrafiltration membranes were prepared from blends of cellulose acetate and carboxylated polysulfones of 0.43 and 0.75 degrees of carboxylation. The effects of degree of carboxylation on membrane characteristics such as compaction, pure water flux, water content and membrane hydraulic resistance, have been investigated to evaluate the performance of the membranes. The influence of the degree of carboxylation on the performance of the blend membranes of various blend polymer compositions has been investigated and also compared with earlier reports on blend membranes prepared from cellulose acetate and polysulfone or carboxylated polysulfone of 0.14 degree of carboxylation. © 2003 Society of Chemical Industry     

Studies on cellulose acetate‐carboxylated polysulfone blend ultrafiltration membranes. III

Enhancement of the hydrophilicity in polymeric membrane materials results in membranes with higher flux and better membrane characteristics. Hence, polysulfone was carboxylated and ultrafiltration membranes were prepared from blends of cellulose acetate and carboxylated polysulfones having various degrees of carboxylation with a total polymer concentration of 20 wt % in casting solution and at different blend polymer compositions. The effects of degree of carboxylation on membrane characteristics such as compaction, pure water flux, and membrane hydraulic resistance (R_m) have been investigated. The influence of the polymer concentration in the blend solution on the performance of blend membranes at various blend polymer compositions has also been investigated and compared with that of blend membranes prepared from blends of cellulose acetate and polysulfone or carboxylated polysulfone with a total polymer concentration of 17.5 wt %. Further, the solute rejection performance of the membranes has also been investigated by subjecting the membranes to metal ion permeation studies using polyelectrolyte‐enhanced ultrafiltration. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 976–988, 2005     

Al_2O_3的添加对聚砜膜性能的影响

报导了用相转化法 (sol- gel)制备聚砜 - Al2 O3共混膜。该膜是将 Al2 O3微粒填充到聚砜中制成的。对该膜的机械性能 ,对含油污水的超滤性能 ,扫描电镜 (SEM) ,亲水性和孔隙率进行了测试。对分散剂和制膜工艺对共混膜性能的影响作了分析。实验发现该共混膜对含油污水具有很好的处理效果     

Separation of propranolol enantiomers through membranes based on chiral derivatized polysulfone

The characterization of new synthesized chiral polymeric membranes, based in polysulfone polymer is here reported. Polysulfone was derivatized to chiral polysulfone, by bonding covalently the chiral carrier, N-dodecyl-4(R)-hydroxy-l-proline, to the polymer matrix. Two different chiral polysulfones, referred to as CPS_A and CPS_B, have been synthesized and used in the preparation of chiral polymeric membranes. However, as a consequence of the limited CPS_B solubility, only CPS_A resulted adequate to obtain useful membranes. Therefore, various chiral polysulfone membranes containing different amounts of CPS_A in unmodified polysulfone (PS) were prepared and properly characterized by scanning electron microscopy (SEM) and by enantioselective transport experiments of racemic propranolol. Dialysis transport experiments allowed us to determine the influence of the carrier content in the membrane on the transport rate and on enantiomer separation. Membranes containing a CPS_A/PS ratio of 1:3 showed an alpha value of 1.1 at 96 h of performance. Modelling of the propranolol transport rate is also performed.     

Pervaporation separation of water/ethanol mixture using asymmetric ion‐exchange membranes containing aluminum ions

The asymmetric aluminum ion exchange polysulfone membranes have successfully been prepared for the dehydration of ethanol‐water mixture. The relationship between the membrane morphology, separation performance, and the ion content of membranes were discussed in this study. The experimental results showed that the separation performance of those membranes was increased upon increasing the degree of aluminum ion exchange in polysulfone membranes. Both permeation rate and separation factors of those membranes increased with increasing the degree of ion exchange. The increase in separation performance of aluminum ion exchange membranes was mainly attributed to ion crosslinking in polymer network and the hydration effects of exchanged ion in membranes. On the other hand, the operating temperature in the PV process showed a significant influence on the dehydration of water molecules in the permeate. An increase in temperature increased the permeation flux of permeate but slightly decreased its selectivity. The aluminum asymmetric ions in membranes showed a strong influence on permselectivity of asymmetric ion exchange membranes. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Effect of Pectinase Immobilization in a Polymeric Membrane on Ultrafiltration of Fluid Foods

The aim of this research was to obtain an enzymatic membrane reactor for use to clarify a model system and apple juice with a 12% soluble solid content and 1 mg/mL of pectin by water-soluble pectinolytic enzymes which were immobilized on polysulfone membranes. These membranes were synthesized in the laboratory by immersion precipitation (phase inversion) from polysulfone with and without active carbon. To ensure the cut-off separation of the membrane in the ultrafiltration process a commercial flat membrane with an 8-kDa molecular weight cut-off was used. The influence of different parameters (viscosity, density, reducing sugars, color, pH, and presence of pectin) on the initial sample and the volumetric permeate flux was also evaluated. The obtained membranes were characterized physically using a scanning electron microscopy SEM and analyses were performed with IFME® software.

The results indicated that immobilization of the enzyme in the membrane allowed an interaction between the recirculating sample and the membrane, the one obtained with activated carbon and immobilized enzymes showed higher degradation of pectin, improving the performance of the volumetric permeate flux.     

聚砜类燃料电池质子交换膜研究进展

介绍了质子交换膜的分类，综述了主链型聚砜质子交换膜、侧链型聚砜质子交换膜、无机掺杂复合型聚砜质子交换膜等聚砜类燃料电池质子交换膜的最新研究进展，全面阐述了磺化聚砜的形貌、结构对材料物理化学性能的影响，并展望了聚砜类燃料电池质子交换膜的发展前景。     

用于反渗透复合膜的海绵状结构支撑膜制备研究

通过调节铸膜液中聚砜浓度和非溶剂含量,浸没沉淀法制备海绵状结构的支撑膜,并在支撑膜上界面聚合制备聚酰胺反渗透复合膜。分别对支撑膜及反渗透复合膜的结构和性能进行表征,考察聚砜浓度对支撑膜结构和性能的影响,以及不同结构支撑膜对反渗透复合膜结构和性能的影响。结果显示,随着聚砜浓度的增加,支撑膜表面孔径和孔隙率下降,断面结构变致密,耐压性增强。在不同支撑膜上制备的反渗透复合膜具有不同的通量和脱盐率。综合考虑支撑膜及反渗透复合膜的性能,以聚砜浓度为15%制备的海绵状结构支撑膜更适于作为制备反渗透复合膜的支撑层。     

Nitric oxide and carbon monoxide permeation through glassy polymeric membranes for carbon dioxide separation

Minor components present in polymeric membrane gas separation can have a significant influence on the separation performance. Carbon monoxide and nitric oxide exist in post-combustion gas streams and can therefore influence CO₂ transport through membranes designed for that application. Here, the permeability of nitric oxide (NO) through three glassy polymeric membranes (polysulfone, Matrimid 5218 and 6FDA-TMPDA) was determined and found to be less than the CO₂ but greater than the N₂ permeability in each membrane. This study also investigated the influence of 1000 ppm CO on the mixed gas permeability of CO₂ and N₂ for two glassy polymeric membranes; polysulfone and 6FDA-TMPDA. For both membranes, CO competitive sorption resulted in a reduction in the measured permeability of CO₂ and N₂ even though present at only low concentration.     

聚砜类分离膜材料及其改性研究进展

讨论了一些常用的聚砜类分离膜材料的结构与性能,从共混、共聚和表面接枝改性等方面对聚砜类膜材料的改性进行了详细的阐述,对聚砜类膜材料的研究与应用前景进行了展望。