酚酞基聚芳醚砜非对称超滤膜凝胶动力学研究

采用耐高温工程塑料——含酚酞侧基的聚芳醚砜(PES-C)为膜材料,草酸和聚乙二醇为添加剂,N,N-二甲基乙酰胺为溶剂,并利用改进的凝胶动力学实验装置和方法,使之能真实地再现不同膜孔结构生长及发展演化的过程,借助相关软件对图像进行处理,考察了添加剂、聚合物浓度对铸膜液凝胶速度的影响,对酚酞基聚芳醚砜非对称膜的凝胶过程的动力学进行研究.结果表明,动力学图像与最终膜结构有很好的一致性,凝胶动力学方面得到了与Strathman等不同的研究结果,发现凝胶前锋位移的平方与时间不是线性关系,凝胶动力学过程不能简单地用Fick扩散定律来描述.     

草酸对非对称膜成膜过程中热力学、流变学和凝胶动力学的影响

以酚酞基聚芳醚砜/草酸/N,N-二甲基乙酰胺为铸膜液体系, 考察了草酸对非对称膜成膜过程中的热力学、流变学和凝胶动力学的影响. 结果表明, 草酸的加入, 在热力学上加速了铸膜液的相分离. 成膜过程中凝胶动力学的研究结果表明, 凝胶前锋位移的平方与时间不是简单的线性关系. 将凝胶过程与非对称膜的结构相对应, 分为4个连续的凝胶过程, 凝胶速度曲线由4段具有不同速度常数的线段组成. 在凝胶过程中, 凝胶速度常数最大的是皮层.     

小分子醇对PVDF／PFSA共混膜凝胶动力学、膜结构及膜性能的影响

以小分子醇为添加剂,研究了小分子醇对聚偏氟乙烯(PVDF)/全氟磺酸(PFSA)共混超滤膜凝胶动力学、结构与渗透性能的影响.结果表明:在PVDF/PFSA铸膜液中添加乙醇时,其凝胶速率随乙醇浓度的增加而加快,超滤膜通量随乙醇浓度的增加而增大;而当添加相同浓度的4种小分子醇时,初始凝胶速率差别不大,20 s后添加乙醇的铸膜液的凝胶速率最大;添加小分子醇后超滤膜的水通量大小顺序为:异丙醇<甲醇<乙醇<正丁醇.SEM照片显示在铸膜液中添加5%乙醇所制备的共混超滤膜具有较为圆整的内腔结构与均匀的孔结构.     

酚酞型聚醚砜(PES-C)超滤膜的制备及性能北大核心CSCD

以聚乙烯吡咯烷酮(PVP)和乙醇(EtOH)为添加剂,采用相转化法制得了酚酞型聚醚砜(PES-C)超滤膜。结果表明:当以乙醇为添加剂时,随着乙醇含量的增加,膜上表面变为致密结构,下表面呈多孔结构,水通量先上升后减小;当以PVP为添加剂时,随着PVP含量增加,PES-C膜的指状孔得到发展,膜通量和截留率都上升,当PVP的质量含量为10%时,PES-C膜的通量达到134.3L/(m2.h),对牛血清蛋白的截留率达85.1%。     

酚酞型聚醚砜（PES—C）超滤膜的制备及性能

以聚乙烯吡咯烷酮（PVP）和乙醇（EtOH）为添加剂,采用相转化法制得了酚酞型聚醚砜（PES-C）超滤膜。结果表明：当以乙醇为添加剂时,随着乙醇含量的增加,膜上表面变为致密结构,下表面呈多孔结构,水通量先上升后减小;当以PVP为添加剂时,随着PVP含量增加,PES—C膜的指状孔得到发展,膜通量和截留率都上升,当PVP的质量含量为10％时,PES—C膜的通量达到134．3L／（m^2·h）,对牛血清蛋白的截留率达85．1％。     

联苯类液晶改性纤维素膜的制备及其抗紫外性能

以1,6-二溴己烷、氰基联苯酚和N-甲基咪唑为主要原料，合成含有咪唑基团的联苯类液晶（CbP）。以离子液体1-烯丙基-3-甲基咪唑氯盐（AMIM·Cl）为溶剂，将木浆纤维素（WPC）与CbP共混得到铸膜液，再通过浸渍沉淀相转化技术将铸膜液制成纤维素液晶膜（WPC/CbP）。采用哈克流变仪对溶液性能进行表征，用傅里叶红外光谱（FT-IR）、X-射线光电子能谱（XPS）、差示扫描量热（DSC）等对膜结构和性能进行表征。结果表明，CbP的引入改变了纤维素分子内及分子间的氢键作用，提高了纤维素膜的热稳定性。当CbP在铸膜液中的质量分数为3%时，溶液黏度最低。与纯纤维素膜相比，此WPC/CbP膜的拉伸强度提高了27.56%，紫外光透光率降低了35%左右。     

聚丙烯腈原液膜的制备和性能

以溶液聚合的聚丙烯腈原液为铸模液，研究了溶液铸腊法工艺参数：铸膜液温度、凝胶水温度、铸膜液浓度等对膜性能的影响。结果表明，不存在蒸发时间的影响以及不调整原液的组分和浓度是聚俩烯腈原液于其它膜制作技术的显著特点。调节有关制膜工艺参数即可获得特定用途的超滤分离膜。在具有三层结构、平均孔径为５ｎｍ的聚丙烯腈原液干膜上复合了聚乙烯醇（ＰＶＡ）的ＰＶＡ／ＰＡＮ复合膜，分离醇水溶液的渗透汽化（ＰＶ）性能优良。     

聚乙二醇对聚醚砜超滤膜微结构和性能的影响

通过改变铸膜液中添加剂PEG的含量，测试了当铸膜液中PES的质量分数为0．21，凝固浴(DM—SO／H2O体系)中DMSO的质量分数为0．10时，所成膜的水通量和尿素、肌酐去除率。研究了PES／DMSO体系中小分子添加剂PEG作用的规律。     

反渗透膜清洗过程中有机污染物和无机离子含量的在线监测

建立了一个可以在线监测反渗透膜(RO膜)清洗过程中有机污染物和无机离子含量变化的系统。纯水循环清洗下来的有机物含量约为8 mg/L,加入超声后有机物含量迅速增加至20 mg/L,说明超声能够显著提高对RO膜上有机物的清洗效果;0.2%草酸循环清洗掉的有机物含量约为136 mg/L,说明草酸对有机物清洗效果很好。RO膜清洗过程中K/Na/Cl/Ca无机离子含量的检测条件为:总离子强度调节液(TISAB)的各离子浓度为0.05μmol/L K~+,0.05μmol/L Ca~(2+)及0.15μmol/L Cl~-;二异丙胺(碱化试剂)浓度为4.5%(V:V);碱化管长度为40cm;采样流速1.5 m L/min。方法的标准添加回收率在96.2%~105.8%之间。     

带酞基聚芳醚酮超滤膜的研究──Ⅰ带酞基聚芳醚酮超滤膜的制备与性能

以带酞基聚芳醚酮（ＰＥＫＭ）为膜材料，用相转换法制备了ＰＥＫ—Ｃ不对称超滤膜，研究了铸膜液的主要组分对膜的孔结构与超滤性能的影响。     

SPEEK/PES-C、SPEEK/SPES-C共混质子交换膜研究

通过在磺化聚醚醚酮(SPEEK,DS=61.68%)中分别混入酚酞型聚醚砜(PES-C)、磺化酚酞型聚醚砜(SPES-C,DS=53.7%)制备出SPEEK/PES-C、SPEEK/SPES-C共混质子交换膜.结果表明,共混的两种聚合物之间均具有较好的相容性.PES-C、SPES-C的混入能有效降低膜的溶胀及甲醇透过,且随着共混量的增加,这种作用越趋明显.纯SPEEK膜在75℃左右溶解,而SPEEK/PES-C(30wt%)、SPEEK/SPES-C(30wt%)共混膜在80℃时溶胀度仅为22.5%、26.32%.在室温至80℃范围内,纯SPEEK及共混膜的甲醇透过系数都在10-7cm2.s-1数量级上,远小于Nafion115膜.在饱和湿度下,温度大于90℃时,SPEEK/PES-C(20wt%)共混膜电导率超过Nafion115膜;温度大于110℃时,SPEEK/SPES-C(30wt%)共混膜电导率与Nafion115膜相当,达到0.11S.cm-1.高电导率,低透醇系数以及明显提高了的可使用温度表明该类共混膜有望在DMFC中使用.     

ULTRAFILTRATION MEMBRANE FORMATION OF PES-C, PES AND PPESK POLYMERS WITH DIFFERENT SOLVENTS

Ultrafiltration membranes were prepared using phenolphthalein polyarylethersulfone (PES-C),polyethersulfone (PES) and poly(phthalazinone ether sulfone ketone) (PPESK) as polymers and NMP,DMAc,DMF and DMSO as solvents by immersion precipitation via phase inversion.Experimental data of thermodynamic properties of the polymer solutions and kinetic process of membrane formation were reported.For polymer solutions with good solvents,the sequence of the viscous flow activation energy (E_η) was coincident with ...     

Permeation of nitrogen and water vapor through sulfonated polyetherethersulfone membrane

The novel polyetherethersulfone (PES-C) prepared from phenol-phthalein in our institute is an amorphous, rigid, tough material with good mechanical properties over a wide temperature range. To improve its water vapor permeability for the application of gas drying, the PES-C was sulfonated with concentrated sulfuric acid and transferred in sodium, cupric, and ferric salt forms. The sulfonation degree can be regulated by controlling the temperature and reaction time. Characterization of sulfonated PES-C in sodium form was made by IR. Some properties of the sulfonated PES-C, such as solubility, glass transition temperature, thermal stability, mechanical properties, and transport properties to nitrogen and water vapor have also been discussed. © 1997 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 35: 2133–2140, 1997     

聚醚砜/酚酞基聚醚砜共混相容性及凝胶特性研究

采用混合热焓法和稀溶液粘度法预测了聚醚砜/酚酞基聚醚砜体系相容性,并观察了聚醚砜/酚酞基聚醚砜共混制膜液的凝胶值与共混比的关系.聚醚砜/酚酞基聚醚砜为部分相容体系,其相容性与组成有关.共混制膜液的凝胶值受共混组成的影响,并非纯组分制膜液凝胶值的线性加和.     

Surface modification of phenolphthalein poly(ether sulfone) ultrafiltration membranes by blending with acrylonitrile-based copolymer containing ionic groups for imparting surface electrical properties

Asymmetric ultrafiltration membranes were fabricated from the blends of phenolphthalein polyethersulfone (PES-C) and acrylonitrile copolymers containing charged groups, poly(acrylonitrile-co-acrylamido methylpropane sulfonic acid) (PAN-co-AMPS). From the surface analysis by XPS and ATR-FTIR, it was found that the charged groups tend to accumulate onto the membrane surface. This result indicated that membrane surface modification for imparting surface electrical properties could be carried out by blending charged polymer. Furthermore, with the help of a relatively novel method to measure membrane conduction, the true zeta potentials calculated on the basis of the streaming potential measurements were used to reflect the charge state of membrane surface. In addition, it was noteworthy that, from the profiles of zeta potential versus pH curves and the magnitude of zeta potentials, the determination of zeta potential was dependent not only on the electrical properties of membrane surface but also on its hydrophilicity. At last, based on a relatively elaborate study on the electrostatic interaction between the membrane surface and protein, it was found that these charged membranes could meet different demands of membrane applications, such as resisting protein fouling or protein separation, through adjusting solution pH value.     

以1,4-二氯甲氧基丁烷为氯甲基化试剂制备线型氯甲基化酚酞聚芳醚砜

采用1,4-二氯甲氧基丁烷（BCMB）为氯甲基化试剂,在Lewis酸ZnO/1,1,2-三氯乙烷的均相反应体系中高效的进行了酚酞聚芳醚砜（PES-C）的氯甲基化,观察了溶剂和催化剂等因素对氯甲基化反应的影响,得到了PES-C氯甲基化的最佳条件。 由1H NMR方法表征了氯甲基化的酚酞聚芳醚砜（CMPES-C）的结构及氯甲基化程度（χCH2Cl-）。 实验结果表明,BCMB完全可以替代氯甲醚,在相似的反应条件下对PES-C树脂进行有效的氯甲基化改性,ZnO/1,1,2-三氯乙烷体系在温和的反应条件下可制得适度的（χCH2Cl-为0.2~0.6）且完全线型结构的CMPES-C。     

Synthesis and optimization of permselective polymer (polyindoline) film

A polyindoline permselective polymer film was readily synthesized by an electrochemical polymerization of indoline in an aqueous solution of KCl at a potential of 0.4 V vs Ag/AgCl. The amperometric responses of the polyindoline film-coated platinum electrodes to electroactive (ascorbic acid, oxalic acid and hydrogen peroxide) and non-electroactive (lactose, sucrose and urea) substances were measured at a potential of 0.7 V. Effects of various variables such as film thickness, concentrations of monomer and electrolyte, and pH on the permselective behavior of the polymeric membrane were systematically investigated and the optimal values were determined. It was found that permselective polyindoline-coated electrodes prepared in this one-step procedure permitted hydrogen peroxide oxidation while it prevented interference due to oxidizable species such as ascorbic acid and oxalic acid. As a result, it is believed that this polymeric membrane, owing to its permselective character, can be used as the protective material in the construction of hydrogen peroxide-based biosensors. Received: 10 November 1997 / Accepted: 27 January 1998     

两种高Tg非线性光学聚合物母体及掺杂,极化的研究

利用具有非线性光学活性的对硝基苯胺掺杂高玻璃化转变温度的聚芳醚砜(PES-C)和聚芳醚酮(PEK-C),得到了两种掺杂含量较高的掺杂型非线性光学聚合物体系。电晕极化表明较高的取向和较慢的松驰。