正交实验法优化氯甲基化聚砜／聚砜共混膜的季铵化条件

将氯甲基化聚砜(CMPSF)/聚砜(PSF)共混膜浸于三甲胺溶液中制得季铵化聚砜(QMPSF)/聚砜(PSF)膜.采用正交实验考察了季铵化反应条件如季铵化温度、季铵化时间、三甲胺浓度等对QMPSF/PSF膜性能的影响,优化了季铵化条件,制得了性能较佳的季铵化QMPSF/PSF膜.研究结果表明,在0.2MPa压力下.制备的季铵化QMPSF/PSF膜的水通量为31.35 L/(m2·h),对相对分子质量为31 000～50 000的聚乙烯醇溶液的截留率为89.6%.     

氧化铝凝胶改性聚偏氟乙烯超滤膜的制备与表征

为提高聚偏氟乙烯超滤膜的亲水性,采用Al_2O_3凝胶对有机高分子聚偏氟乙烯膜进行改性,制备Al_2O_3凝胶改性聚偏氟乙烯超滤膜,并与非凝胶化无机纳米Al_2O_3颗粒改性进行对比。考察铸膜液中Al_2O_3凝胶加入量对改性聚偏氟乙烯超滤膜性能和结构的影响。采用扫描电镜、X射线能谱、傅里叶红外光谱和超滤实验等对超滤膜结构和性能进行表征,结果表明,Al_2O_3凝胶加入量1.0 g时,改性超滤膜水通量提高5.48倍;扫描电镜表明,改性超滤膜和未改性超滤膜均为典型的非对称结构,改性超滤膜表面孔数目明显增加,断面微观结构未发生改变;红外光谱及能谱分析表明,Al_2O_3凝胶与高分子聚偏氟乙烯之间为物理共混。Al_2O_3凝胶改性聚偏氟乙烯超滤膜,改善了膜表面亲水性,提高水通量,并保持较大截留率。     

氯甲基化/季铵化新型聚芳醚砜酮超滤膜的研制

本文对含二氮杂萘结构聚芳醚砜酮进行改性制得氯甲基化聚芳醚砜酮。选用N-甲基一2-吡咯烷酮作制膜溶剂，依据正交设计方法制得了一系列氯甲基化聚芳醚砜酮超滤膜。考察了聚合物浓度、添加剂种类和添加量以及制膜蒸发时间等对膜性能的影响。将氯甲基化聚芳醚砜酮超滤膜浸入三甲胺溶液进行季铵化反应，得季铵化聚芳醚砜酮超滤膜。并考察了膜的抗污染性。     

平板式共混超滤膜的研究

本文报道了聚砜酰胺，聚砜酰胺／磺化聚芳醚砜，聚偏二氟乙烯／磺化聚芳醚砜平板超滤膜的制备工作，所得膜截留分子量分别为３００００－７００００，１０００－２００００，１０００００。并并对北京醋进行了澄清过滤试验，工业试验结果表明，用ＰＶＤＦ／ＳＰＥＳ－Ｃ超滤膜，２０ｍ＾２平板超滤机上醋产量为６００－８００Ｌ／ｍ＾２．ｈ，产量稳定，清洗容易，满足生产需要。     

水中汞离子净化用共混改性超滤膜的研制

采用相转化法,以聚偏氟乙烯（PVDF）、二硫化二苯并噻唑、聚乙二醇（PECA00）、吐温80和N,N-二甲基乙酰胺（DMAe）为原料制备具有汞离子吸附能力的二硫化二苯并噻唑共混改性聚偏氟乙烯超滤膜,并对影响超滤膜结构和性能的各个因素进行了研究。结果表明,在二硫化二苯并噻唑质量分数为0．4％、共混温度为70℃、共混时间为6h条件下所制备的超滤膜性能最佳。在25℃、0．1MPa下,膜的纯水通量为312L／m^2·h,卵清蛋白截留率为83．46％,接触角为72．35°;在25℃、pH值为7左右的条件下,膜吸附汞离子在6h达到吸附平衡。汞离子最大吸附量为0．331mg／cm^2。     

壳聚糖季铵盐改性聚砜超滤膜的研究

将聚砜的N,N-二甲基乙酰胺溶液与壳聚糖季铵盐的二甲基亚砜溶液共混,其中二甲基亚砜中预先加入适量戊二醛,N,N-二甲基乙酰胺中加入无水氯化锌,以聚酯类无纺布作为支撑层,采用浸没沉淀相转化制备了壳聚糖季铵盐/聚砜共混改性超滤膜并经热处理,通过粘度测试对比了共混溶液与纯聚砜溶液的粘度,通过测试水通量、牛血清蛋白脱除率研究了膜片的分离性能,通过接触角实验和耐污染实验表征了膜的表面亲水性变化和膜片耐污染性,通过扫描电镜观察膜的结构。研究结果表明,共混溶液粘度相比聚砜溶液得到了提高,壳聚糖季铵盐的引入提高了超滤膜的亲水性和耐污染性,相比未共混聚砜膜,季铵化壳聚糖共混改性聚砜膜膜片在膜性能上得到了显著的提高,最优化条件所制得膜片水通量测试结果为70 L/(m2·h),对牛血清蛋白的截留率为99.5%。     

聚偏氟乙烯有机-无机超滤膜性能影响因素的研究进展

介绍了影响聚偏氟乙烯有机-无机超滤膜性能的主要因素,研究了相转化法制备聚偏氟乙烯有机-无机超滤膜的主要控制参数,如聚偏氟乙烯含量、无机填料、溶剂、添加剂、凝胶浴温度、蒸发时间等,探讨了有机-无机超滤膜的研究方向。     

低压季铵化聚砜反渗透膜

本文研究了氯甲基化/季铵化聚砜的合成、制膜工艺及其反渗透性能。采用了氯甲基化聚砜、硝酸锂及二甲基乙酰胺的溶液先制备不对称膜,然后以三甲胺溶液进行季铵化反应制备反渗透膜的新工艺。该膜在操作压力为1.5MPa,浓缩水回流量为20L/h,进料液为自来水的条件下,脱盐率为92％,水通量为0.6m~3/m~·d。     

紫外光接枝甲基丙烯酸二甲胺乙酯制备抗菌分离膜

将乙胺直接加到聚偏氟乙烯铸膜液中制备含碳碳双键的聚偏氟乙烯膜,在不除氧和无光引发剂条件下,采用紫外光直接辐射将抗菌单体甲基丙烯酸二甲胺乙酯(DMAEMA)接枝到聚偏氟乙烯膜表面,利用氯化苄对接枝DMAEMA的膜进行季铵化改性,制备了具有抗菌性的聚偏氟乙烯分离膜。考察不同接枝率膜的抗菌效果,接枝改性后膜的抗菌效果随接枝率增大而增加,同时随时间的延长而增强。经稀盐酸洗涤后,膜的抗菌效果并无明显变化,表明紫外光接枝改性后的聚偏氟乙烯分离膜具有较稳定的抗菌性。     

季铵化聚砜和季膦化聚砜共混阴离子交换膜的制备与表征

以聚砜为基材制备阴离子导电膜材料。将季膦化聚砜铸膜液与已证实成膜性能良好的季铵化聚砜共混,制备QAPSFOH/QPPSFOH共混阴离子交换膜,以改善季膦化聚砜成膜困难问题。通过改变两种成分比例,可以得到不同性能的阴离子交换膜。在QAPSF与QPPSF摩尔比为1∶2时,共混膜电导率达0.030 9 S/cm,拉伸强度达775 MPa,热分解温度达160℃,满足实际情况对阴离子交换膜的需要。     

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     

Influence of triphenylphosphonium pendant groups on the rheological and morphological properties of new quaternized polysulfone

A new quaternized polysulfone with triphenylphosphonium pendant groups was synthesized by reacting chloromethylated polysulfone with triphenylphosphine. The molecular restructurations, generated by hydrogen bonding, electrostatic interactions, and association phenomena in ternary quaternized polysulfone/N,N‐dimethylformamide (solvent)/water (nonsolvent) systems, were evaluated by rheological investigations. The polyelectrolyte effect, induced by enhanced dissociation of the ionizable groups and by mixed solvents' quality, modify the rheological functions, that is, dynamic viscosity, elastic shear modulus, and viscous shear modulus, as well as the thermodynamic parameters obtained from the rheological properties, such as apparent activation energy. These results were correlated with the morphological properties of the films obtained from solutions in solvent/nonsolvent mixtures and compared with other quaternized polysulfones, having different hydrophobic characteristics. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Cellulose acetate and sulfonated polysulfone blend ultrafiltration membranes. I. Preparation and characterization

Modification of polymeric membrane materials by incorporation of hydrophilicity results in membranes with low fouling behavior and high flux. Hence, Polysulfone was functionalized by sulfonation and ultrafiltration membranes were prepared based on sulfonated polysulfone and cellulose acetate in various blend compositions. Polyethyleneglycol 600 was employed as a nonsolvent additive in various concentrations to the casting solution to improve the ultrafiltration performance of the resulting membranes. The total polymer concentration, cellulose acetate, and sulfonated polysulfone polymer blend composition, additive concentration, and its compatibility with polymer blends were optimized. The membranes prepared were characterized in terms of compaction, pure water flux, membrane resistance, and water content. The compaction takes place within 3–4 h for all the membranes. The pure water flux is determined largely by the composition of sulfonated polysulfone and concentration of additive. Membrane resistance is inversely proportional to pure water flux, and water content is proportional to pure water flux for all the membranes. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 1749–1761, 2002     

阴极电泳涂料的发展趋势

阴极电泳涂料作为一种环保型的水性涂料,具有广阔的应用前景。介绍了电沉积原理,阴极电泳涂料树脂的特点以及阴极电泳涂料的优越性。概述了国内外阴极电泳涂料的现状及需求,重点介绍了几类目前发展较快的阴极电泳涂料,同时指出了阴极电泳涂料今后的发展趋势。     

Preparation of bipolar membranes. II

The bipolar multilayer membrane was prepared by a new technique. The interfacial layer and cation layer were formed by only one step. The anion and cation layers were made from the same material from which chloromethylated polysulfone was used as a basic material. The bipolar membranes were composed of a solvent‐resistant anion layer with crosslinking matrix by the reaction of chloromethylated polysulfone in DMF with diamine; an ultrathin interfacial layer from chloromethylated polysulfone solution in DMF, containing cation‐exchange resin and both quaternary and nonquaternary amine groups; and a cation layer from chloromethylated polysulfone dispersing cation resin powder. The prepared bipolar membrane exhibits a lower voltage drop over 100 mA/cm² and stable performances at a long‐term operation. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1733–1738, 2001     

Quaternized polysulfone‐based nanocomposite membranes and improved properties by intercalated layered double hydroxide

Two anions (dodecylbenzenesulfonate anion and stearate anion) are employed to synthesize intercalated layered double hydroxides (LDH) by co‐precipitation method. Then the intercalated LDHs are incorporated in the casting solutions of chloromethylated polysulfone (CMPSF) for fabricating quaternized polysulfone/LDH nanocomposite membranes. Fourier transform infrared, X‐ray diffraction, thermogravimetric analysis, scanning electron microscopy, and mastersizer laser particle size analysis are used to characterize the structure and morphology of LDHs and membranes. The properties of the composite membranes including water uptake, mechanical property, thermal stability, and ionic conductivity are investigated. Compared with other anion exchange membranes, both nanocomposite membranes containing 5% LDH sheets displayed better balanced performance. They exhibit the ionic conductivity of 3.58 × 10^?2 S cm^?1 and 3.86 × 10^?2 S cm^?1 at 60°C, respectively. POLYM. ENG. SCI., 2017. © 2017 Society of Plastics Engineers     

Preparation of bipolar membranes (I)

The bipolar membranes were prepared by charged material of polysulfone as a base. The bipolar membranes were composed of a solvent‐resistant anion exchange layer with a crosslinking matrix prepared by the reaction of chloromethylated polysulfone in DMF with diamine, an interfacial layer made from chloromethylated polysulfone solution in DMF containing cation exchange resin and amine, and a cation exchange layer made from sulfonated polysulfone dispersing cation resin powder. The prepared bipolar membrane can exhibit lower voltage drop over 100 mA/cm². The critical requirement for producing bipolar membranes of low potential drop is the creation of a thin interfacial region with a low electrical resistance and a suitable chemical structure, which act to catalyze water splitting. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 80: 1658–1663, 2001     

Preparation of a novel phthalimidomethylated polysulfone/unmodified polysulfone blend affinity membrane and applications for removal of p‐nitrophenol

A novel phthalimidomethyl polysulfone (PIPSf)/polysulfone(PSf) blend affinity membrane was prepared and applied for the removal of p‐nitrophenol from aqueous solutions. In this work, the chloromethylated polysulfone (CMPSf) was used to introduce phthalimido groups onto the polysulfone backbone by Gabriel reaction. The polymers can be easy to phthalimidomethylate to different degrees by control of the reaction temperature and time. Structures of the resulting polymers were confirmed by FT‐IR. The obtained polymers showed good solubility in dimethylformamide, dimethylacetamide and formed the affinity membrane blending with polysulfone at different blend compositions by the phase‐inversion method. Thus the properties of films were characterized with respect to water flux, pore size, and porosity. The surface and cross‐sectional views of the blend membranes were analyzed by scanning electron microscopy (SEM). The research on treatment of removal p‐nitrophenol was carried out by affinity membrane process. The adsorption capacity increased with increasing the initial concentration of p‐nitrophenol in aqueous solution, and the adsorption isotherm fitted the Freundlichmodel well. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

Determination of Membrane Protein Fouling by UV Spectroscopy and Electrochemical Impedance Spectroscopy

UV spectroscopy and electrochemical impedance spectroscopy were used to investigate the properties and performances of ultrafiltration membranes fabricated with different polymers. Membrane performances were studied by means of permeability and bovine serum albumin filtration. UV spectroscopy results showed that bovine serum albumin rejection was lowest in polyvinylidene fluoride membranes, whereas it was highest in polysulfone membranes. Electrochemical impedance spectroscopy data revealed that after bovine serum albumin filtration, resistance of the membranes was increased though double layer capacitances were decreased. Performance data of UV spectroscopy and electrochemical impedance spectroscopy were in correlation with each other. This study demonstrated that electrochemical impedance spectroscopy can be successfully used in filtration membrane studies.