纤维编织管增强型中空纤维膜研究

采用二维编织技术将聚丙烯腈(PAN)长丝编织成中空纤维编织管作为增强体,分别以聚丙烯腈(PAN)和聚偏氟乙烯(PVDF)为成膜聚合物,N,N-二甲基乙酰胺(DMAc)为溶剂,聚乙烯吡咯烷酮(PVP)为添加剂,调制铸膜液,采用同心圆挤出-涂覆法制备了PAN纤维编织管同质增强型PAN中空纤维膜和异质增强型PVDF中空纤维膜.研究表明,所得PAN纤维编织管增强型中空纤维膜断裂强度最大可超过75 MPa,在伸长率10%范围内,表面分离层与增强体之间界面结合良好;表面分离层具有类似于非对称膜的结构,铸膜液可浸入纤维编织管纤维空隙中,铸膜液浸入部分固化后未影响膜的通透性能;随成膜聚合物浓度增加,膜纯水通量减小,牛血清白蛋白(BSA)截留率增大;随添加剂PVP浓度增加,膜的纯水通量先增大后减小,在8 wt%左右达最大值,BSA截留率随PVP浓度增加而单调增加;同质增强型中空纤维膜界面结合程度优于异质增强型.     

聚偏氟乙烯中空纤维膜器对钐传质性能的影响

以Ｐ５０７－煤油ＨＣｌ－Ｓｍ为实验体系,在两种聚偏氟乙烯中空纤维膜器中研究了溶胀性能、反萃酸度对基于水相的总传质系数及中空纤维膜孔径的影响,考察了料液酸度、萃取剂浓度、钐离子浓度与萃取速率的关系。获得了相应的反应级数。根据界面反应动力学,得到了速率常数值和动力学方程。     

熔纺聚氨酯系中空纤维膜的结构与性能

将聚氨酯/聚偏氟乙烯/聚乙二醇(PU/PVDF/PEG)熔融共混纺丝制得中空纤维膜,对纤维膜的微孔结构与性能进行研究,分析影响其水通量衰减的因素。结果表明:所得纤维膜具有界面及非界面微孔结构;随着水通量工作环境的变化,膜孔结构发生相应变化,表现出压力及温度响应性能;而经热处理后,所得膜部分微孔闭合,水通量下降;随测试时间延长,膜结构趋于致密化,水通量衰减。     

聚偏氟乙烯中空纤维亲和膜分离γ—球蛋白的研究（I）——聚偏氟乙烯中空纤维亲和膜的制备及其吸附性能

对聚偏氟乙烯(PVDF)中空纤维膜进行表面亲水化处理，再经活化、偶联制得了带有苯丙氨酸(Phe)的PVDF中空纤维亲和膜。制备过程中以光电子能谱(XPS)及红外光谱分析膜表面基团的变化，经亲水化处理及活化偶联后，膜表面的O和N含量分别从5．6％和0.6％增加到16．5％和3．0％，而F含量由38．3％降低为23．0％。将该亲和膜用于室温下血浆中γ—球蛋白的分离实验，在pH＝7．4，离子强度I＝0.18的缓冲液体系及进料质量浓度为1．0mg／mL条件下，该亲和膜对γ—球蛋白的吸附量可达到5．85mg／g膜；与市售γ-球蛋白相比，血浆中提取纯度可达83.9%。     

熔融纺丝-拉伸法制备PVDF中空纤维膜及其油-水分离性能

以聚偏氟乙烯(PVDF)为成膜聚合物, 聚全氟乙丙烯(FEP)为添加剂, 聚乙二醇(PEG)和氯化钙(CaCl₂)为复合成孔剂, 采用熔融纺丝-拉伸法制备了PVDF中空纤维膜. 在制膜过程中未使用其它溶剂和稀释剂, 实现了制膜过程的相对绿色化. 分析和讨论了拉伸比对PVDF中空纤维膜结构与性能的影响, 测试了纤维膜的孔径分布、 力学性能和油-水分离性能等. 结果表明, 进行拉伸后处理的膜的孔径分布较窄, 在油包水乳液分离测试中, 分离效率均在97%以上, 表现出良好的油-水分离效果.     

聚偏氟乙烯中空纤维亲和膜分离γ-球蛋白的研究(Ⅰ)——聚偏氟乙烯中空纤维亲和膜的制备及其吸附性能

对聚偏氟乙烯(PVDF)中空纤维膜进行表面亲水化处理,再经活化、偶联制得了带有苯丙氨酸(Phe)的PVDF中空纤维亲和膜.制备过程中以光电子能谱(XPS)及红外光谱分析膜表面基团的变化,经亲水化处理及活化偶联后,膜表面的O和N含量分别从5.6％和0.6％增加到16.5％和3.0％,而F含量由38.3％降低为23.0％,将该亲和膜用于室温下血浆中γ-球蛋白的分离实验,在pH=7.4,离子强度I=0.18的缓冲液体系及进料质量浓度为1.0mg/mL条件下,该亲和膜对γ-球蛋白的吸附量可达到5.85mg/g膜;与市售γ-球蛋白相比,血浆中提取纯度可达83.9％。     

氧化铝中空纤维膜的制备与表征

 介绍了铝氧化反应结合技术与干湿法纺丝工艺相结合制备氧化铝中空纤维膜的方法．采用热重分析、能量色散谱、X射线衍射、热机械分析和扫描电镜等手段对烧结过程中的反应行为、相转变及膜的微观结构进行了研究．结果表明,所制备的氧化铝中空纤维膜具有非对称结构的特点,其孔隙率高（50．1％）、孔径分布窄（平均孔径0．88μm）、机械强度高（压缩强度和弯曲强度分别为89．6和41．1MPa）．气体的渗透实验结果表明,所制备的膜无针孔、裂纹等缺陷,并且具有良好的渗透性．     

高性能MWCNTs-OH修饰聚偏氟乙烯中空纤维超滤膜的制备

以羟基多壁碳纳米管(MWCNTs-OH)作为添加剂,采用非溶剂致相转化法制备MWCNTs-OH修饰聚偏氟乙烯中空纤维超滤膜.先将MWCNTs-OH加入溶剂N,N-二甲基乙酰胺(DMAC)中超声处理以加强其分散性,力求制得均一铸膜液.通过水通量、截留率、红外光谱,XRD及力学性能测试表征膜性能,并用SEM观察其形貌.重点考察MWCNTs-OH对中空纤维膜通量、截留和力学性能的影响.结果表明,当MWCNTs-OH质量分数从0增加到0.09 wt%时,修饰膜的水通量由376.40 L/m2h增加到510.90 L/m2h,而对BSA截留率保持稳定(95%以上);膜的拉伸强度由1.68 MPa提高到2.42 MPa,断裂伸长率由44.18%提高到76.93%.SEM和TEM研究表明,MWCNTs-OH添加量较少时,在膜中可均匀分散,添加量大时则容易团聚.XRD和IR图谱分析表明MWCNTs-OH参与聚合物结晶过程而未改变聚合物晶型.     

超亲水聚偏氟乙烯中空纤维膜的制备及性能

采用超声辅助接枝聚合技术,将甲基丙烯酸缩水甘油酯(GMA)接枝到聚偏氟乙烯(PVDF)膜表面,制备PVDF-g-GMA膜;再利用氨基诱导环氧基团发生开环反应,将苏氨酸(Thr)接枝到PVDF-g-GMA膜表面,制备了具有两性离子结构表面的PVDF-g-GMA-Thr膜。通过衰减全反射傅里叶变换红外光谱(ATR-FTIR)、X射线光电子能谱(XPS)、接触角测试仪、场发射扫描电子显微镜(FESEM)和牛血清白蛋白(BSA)过滤实验等系统研究了改性前后PVDF膜表面的化学组成、润湿性能、表面形貌和抗污染性能。研究结果表明,随着PVDF-g-GMA接枝Thr反应时间的增加,PVDF-g-GMA-Thr膜的亲水性能明显提高,接触角从90°降为0°,呈现出超亲水性能。同时PVDF-g-GMA-Thr膜的水通量明显提高,当Thr诱导开环反应时间为12 h时,PVDF-gGMA-Thr膜的水通量高达686 L/(m²·h),与PVDF原膜相比,水通量提高了204. 5%。在BSA的过滤测试中,与PVDF膜相比,PVDF-g-GMA-Thr膜呈现出良好的截留性能和抗污染性能,BS...     

PDA/PVDF紫外线屏蔽复合膜的制备及性能表征

利用多巴胺在溶液中自聚得到聚多巴胺(PDA)颗粒, 然后将其作为填料加入聚偏氟乙烯(PVDF)中, 采用溶液成膜法制备具有紫外线屏蔽功能的PDA/PVDF复合膜. 通过傅里叶变换红外光谱(FTIR)、 扫描电子显微镜(SEM)和紫外可见分光光度计(UV-Vis)对制备的PDA颗粒的结构、 形貌以及吸光度进行表征, 并且进一步利用X 射线衍射仪(XRD)、 差示扫描量热仪(DSC)、 热失重分析仪(TGA)、 接触角测量仪(CA)以及紫外老化箱等对PDA/PVDF复合膜的结构、 热性能、 润湿性能与紫外线屏蔽性能进行测试. 结果表明, 制备的PDA颗粒的粒径约为160 nm; 掺杂PDA之后的PVDF膜的结晶度以及接触角均减小; 并且PDA质量分数为5%时得到的PDA/PVDF复合膜在200400 nm范围内的透过率均低于1%, 能够吸收所有的紫外线, 表现出优异的紫外线屏蔽功能.     

PREPARATION AND CHARACTERIZATION OF ION EXCHANGE MEMBRANES BASED ON POLYVINYLIDENE FLUORIDE

 A new ion exchange membrane based on polyvinylidene fluoride (PVDF) and sulfonated poly(styrene- divinylbenzene) was prepared by in-situ polymerization. The incorporation of sulfonic groups into the polyvinylidene fluoride composite membrane was confirmed by infrared spectroscopy (IR), ion exchange capacity (IEC) and energy dispersive X-ray analysis (EDAX). Area resistance, IEC and water uptake of the treated membrane were evaluated. When 20% of the crosslinked membrane was sulfonated at 80°C for 22 h, the PVDF ion exchange membrane can attain 0.8 Ω·cm²area resistance in NaCl aqueous solution at 25℃, IEC is as high as 2.43 millimoles per gram of the wet membrane. The hydrophilicity of PVDF membrane is also significantly improved after treatment. When 60% of crosslinked membrane was sulfonated at 80 ℃ for 6 h, water uptake of the treated membrane can attain 64.7%.     

负载型TiO2-聚酰亚胺亲水复合膜的制备与分离性能

采用溶解－流涎法，湿相转换法和干湿相转换法制轩了负载型ＴｉＯ２－聚酰亚胺亲水复合膜，采用扫描电镜，红外光谱，压汞和透气性实验等手段对该膜的孔径分布，表面结构及扩散性能进行了表征，并讨论了制备亲水对膜孔结构的影响，实验结果表明，三种膜均具有很好的亲水性能，而干湿相转换膜具有良好的孔径分布和分离性能。     

STRUCTURE AND PROPERTIES OF COMPOSITE POLYURETHANE HOLLOW FIBER MEMBRANES

Composite polyurethane (PU)-SiO2 hollow fiber membranes were successfully prepared via optimizing the technique of dry-jet wet spinning, and their pressure-responsibilities were confirmed by the relationships of pure water fluxtransmembrane pressure (PWF-TP) for the first time. The origin for this phenomenon was analyzed on the basis of membrane structure and material characteristics. The effects of SiO2 content on the structure and properties of membrane were investigated. The experimental results indicated that SiO2 in membrane created a great many interfacial micro-voids and played an important role in pressure-responsibility, PWF and rejection of membrane: with the increase of SiO2 content, the ability of membrane recovery weakened, PWF increased, and rejection decreased slightly.     

硅藻土-莫来石复合陶瓷膜支承体的制备及表征

利用硅藻土微粒骨架孔作为孔道,以莫来石为硅藻土微粒的粘连剂,采用溶剂－胶胶－烧结技术制得了硅藻土－莫来石复合陶 膜支承体,这种膜支承体孔径集中于２μｍ左右,孔隙率约为０．４,耐中度大于４．５ＭＰａ,是一种品质优良的膜支承体材料,在综合考察基制造工艺过程和条件的基础上,提出了一个新的复合陶瓷膜支承体烧制模型。     

PREPARATION AND CHARACTERIZATION OF ION EXCHANGE MEMBRANES BASED ON POLYVINYLIDENE FLUORIDE

A new ion exchange membrane based on polyvinylidene fluoride (PVDF) and sulfonated poly(styrenedivinylbenzene) was prepared by in-situ polymerization. The incorporation of sulfonic groups into the polyvinylidene fluoride composite membrane was confirmed by infrared spectroscopy (IR), ion exchange capacity (IEC) and energy dispersive X-ray analysis (EDAX). Area resistance, IEC and water uptake of the treated membrane were evaluated. When area resistance in NaCl aqueous solution at 25℃, IEC is as high as 2.43 millimoles per gram of the wet membrane. The hydrophilicity of PVDF membrane is also significantly improved after treatment. When 60% of crosslinked membrane was sulfonated at 80℃ for 6 h, water uptake of the treated membrane can attain 64.7%.     

PREPARATION OF POLYVINYLIDENE FLUORIDE／POLYVINYL DIMETHYLSILOXANE COMPOSITE HOLLOW FIBER MEMBRANES AND THEIR SEPARATION PROPERTIES

Microporous polyvinylidene fluoride (PVDF) hollow fibre membranes were spun using the dry-wet phase inversion method. By means of dip-coating technique, a uniform coating with thickness of around 5-12μm of polyvinyl dimethylsiloxane (PVDMS) was formed on the surface of porous PVDF hollow fibers. The structural parameters of PVDF substrate membrane were estimated by gas permeation test. Using N2/O2 as the medium, the separation properties of PVDMS-PVDF composite hollow fiber membranes were also evaluated experimentally. The experimental data of both permeability and selectivity are in good agreement with the theoretical results predicted by the presented pore-distribution model, in order to obtain the compact composite membrane free of defects by the dip-coating technique, the thickness of PVDMS skin must be higher than 5μm.     

mCMC-PEG/mCS-PEG双极膜的制备与表征

以Fe3+改性羧甲基纤维素(mCMC)和聚乙二醇(PEG)共混为阳膜;以戊二醛改性壳聚糖(mCS)和聚乙二醇共混为阴膜,制备了mCMC-PEG/mCS-PEG双极膜.以FTIR测定了膜红外光谱,以扫描电镜观察了膜表面和界面层的形态,以TG进行膜的热重分析.测定了mCMC-PEG和mCS-PEG不同比例共混膜的含水率、离子交换容量、溶胀度,及mCMC-PEG/mCS-PEG双极膜的电性能.研究结果表明,在双极膜材料中引入亲水性的聚乙二醇后,因分子间的相容性增大,故而提高了双极膜的离子交换容量,并减小了膜的溶胀性.当CMC∶PEG质量比等于10∶1和CS∶PEG质量比等于2∶1时所制得的双极膜具有良好的电化学性能,在酸碱溶液中机械强度高、溶胀小.     

PREPARATION AND CHARACTERIZATION OF SOLUBLE EGGSHELL MEMBRANE PROTEIN/CHITOSAN BLEND FILMS

Biopolymer chitosan was used to modify the mechanical properties of soluble eggshell membrane protein(SEP) films.The SEP/chitosan blend films were prepared by solution casting from 10%aqueous acetic acid.Tensile strength and elongation at break of the blend films increased with increasing amount of chitosan.Microphase separation was observed by field emission scanning electron microscopy,although interaction between the two components was revealed by FTIR.The biocompatibility of SEP/chitosan blend films ...     

PS/CaCO3复合纳米粒子及PS纳米空心球的制备研究

以CaCO3为核,采用原位乳液聚合法合成了表面接枝型和交联型PS/CaCO3复合纳米粒子,然后用稀盐酸刻蚀,得到PS纳米空心球.考察了乳化剂类型和用量、引发剂加入方式、加料间隔对乳液稳定性以及复合粒子收率、PS接枝效率的影响,并采用TGA、FT-IR和TEM等手段对刻蚀前后粒子的组成及形貌进行了表征.结果表明,阳离子型乳化剂更有利于乳液体系的稳定性;CTAB用量为3.7%~5.5%时,可获得较高的收率和接枝效率,随CTAB用量增加,粒径减小,分布变宽;AIBN应避免和单体、CaCO3粒子一起超声波处理,否则会导致不可逆凝聚;随着加料间隔延长,收率和接枝效率下降,一步加料法可获得具有高收率和高接枝效率(或交联程度)的复合粒子;经刻蚀,两种类型的复合粒子均可以制得空心粒子,但经过交联的聚合物外壳具有更好的尺寸和形状稳定性,刻蚀后仍然能保持球状的外形.     

复合微球的制备、性能及应用

本文综述了复合微球的制备、性能及其应用，并对其发展趋势作了展望．